Garand load

[Unclenick]

I'm apparently lucky that the rounds I have shot thus far have not killed me or blown up my gun.

Technically that's correct. It's true for every round you fire in any gun, though, at least in some small degree. We had a member at The Shooter's Forum who had fired many tens of thousands of rounds of commercial handgun ammunition doing evaluation testing for government agencies. He pointed out that if you fire enough factory ammunition you eventually see examples of every kind of error a handloader might ever make, plus a few a handloader is unlikely to make. Hot loads, no-powder loads, no-primer loads, inverted primer insertion, plus cases with no flash hole or a seated bullet jacket with no lead core in it. So it takes luck, but just doesn't require a lot not to have these problems in your personal experience, given the smaller volume of ammunition the average shooter puts down range.

I know that it is psychologically difficult to accept that one's personal experience of zero problems doesn't prove anything more than that it's possible to have such an experience. Thank goodness, most do. I also know most people driving GM cars with the faulty ignition switch never had a problem, either. Does that mean that if you have one of these cars you will ignore the recall and not spend the time and gas it takes to get it to an authorized repair center to be replaced? Would you let your kids drive it unfixed? No. You maximize your odds and your kid's odds because it is cheap and simple to do.

What may be missing here, is a quantification of how much luck is required to stay safe while ignoring advice to optimize your chances of avoiding a problem. In the Garand, specifically, at the match I mentioned where a round of LC ammo slamfired, there was just that one incident. We had 500 participants in 4 relays at Perry's Viale Range shooting the 50 round National Match course. That's 25,000 rounds put downrange, enough to shoot out 5 barrels on a single gun, and yet only one incident. If you haven't shot 25,000 rounds of M2 Ball in Garands, you still haven't given yourself an even chance to experience the problem, and it probably takes more than that if the gun is in good shape.

It is also important to point out the gun that had the slamfire was pulled off the line right after it happened, of course, and a substitute was put in. So that gun didn't get a chance to repeat that behavior and was set aside so military team armorers could check it when they came in for the National Matches later that year. They have the proper gauging tools, of course. Whether or not it turned out the gun was at fault or the round was defective, I don't know.

I've seen up to 3 slamfires at large matches, and I've seen none at all at others. This was during the Garand and M1A era of service rifle match shooting. I don't believe I've ever been present for an AR slamfire, likely for the reasons mentioned in Slamfire's post. And all the slamfires I've been present for except that one round of LC ammo, have always been with handloads. Member Hummer70 says he's looked at the ammo every time there's been a slamfire at a match he's attended, and thus far has always found high primers among the shooter's remaining ammunition. So, high primers are most often the cause—just not always. Bottom line, though, even with handloads, on average, I would guess from what I've been present for that one chance in twenty-thousand rounds is probably in the ballpark for the slamfire rate with those guns. But that doesn't segregate the rate of issues with the guns from the rate of issues with sloppy handloading.

So that's the situation. You have to shoot a lot, or the odds are you won't see a problem. It's just that for some unlucky individuals, the odds don't play out.

Slamfire is correct about the Garand and M14 mechanisms. They both depend on the base of the cartridge case being push fed by the extractor to keep the primer away from the firing pin during stripping a round from the clip and feeding it into the chamber. It then snaps over the rim as the bolt closes, during which time the receiver "safety" bridge blocks the firing pin until that operation is complete. In an OOB fire, the extractor somehow snaps over the rim of the case before the bolt closes. It takes the round's feed meeting some kind of resistance for that to happen. The broken case I suggested is just one possible cause of that. You can avoid that cause by inspecting cases properly, annealing them periodically, or just retiring the brass after four or five reloadings, as John Feamster used to recommend doing.

As to the small base dies, you can tell by measuring whether or not standard dies are adequate. My best guess is that it is difficult to find an example of a standard die failing to adequately resize cases fired in your own chamber unless it is very tight. It's the odd fat boy from another gun getting past you that is the main concern, and if your chamber is fat or loose, even that won't be an issue. Every once in awhile we get an AR owner reporting inadequate feed reliability if they don't use a small base die. Presumably the odd Garand or M14/M1A is like that, too. For that reason, I would not ignore feed failures in these weapons. You want to find the cause and cure so you don't have slamfire or OOB fire issues.

 

[Slamfire]

I don't believe I've ever been present for an AR slamfire, likely for the reasons mentioned in Slamfire's post. And all the slamfires I've been present for except that one round of LC ammo, have always been with handloads.

AR15’s slamfire. They slamfire in battery, I met a credible source who claimed witnessing an out of battery slamfire, with Government M4’s, firing federal Gold Medal match. I have no idea how that could have happened. This appears to be an out of battery AR15 slamfire, the shooter was using factory ammunition, it is very puzzling https://forums.1911forum.com/showthread.php?t=423194

I have not heard of any other out of battery slamfires in AR's and of the ones I have heard, I don't know how it could happen. I have had, seen another, and heard of in battery slamfires.

Mine occurred during the NRA standing slowfire stage of a highpower match. I was using the brass colored WSR primers. Winchester nickle primers used to be the primer I preferred to use, never had an issue, but these brass colored WSR are thin and pierce easy. My AR also slamfired, in battery.

The bud with whom I was squadded, his AR slamfired with a Federal primer, during his standing relay. Years later, he had another AR15 slamfire with Federal primers during the standing stage and stopped using them.

What characterizes the standing stage from all other stages is that the rifle is loaded single shot while standing. (That you shoot the standing stage while standing ought to be obvious from the name.) However because you are standing, most people lower the muzzle, drop the round in the chamber, and hit the bolt release while the muzzle is down. Enough slamfires occur standing that it has become evident that the little extra bolt acceleration due to gravity is enough to set off the occasional primer.

The NRA banned loading on the stool. I used to see shooters balancing their muzzles on their shooting stool, drop a round, hit the bolt release. I will bet someone’s rifle slamfired through the stool and that is why it is now illegal to load on the stool. I can just imagine the consternation on the line when some poor schmuck blew out the bottom of his shooting stool with all his equipment inside. I hope no one shot their foot. A 223 round in the foot would cause a nasty wound.

I have stopped dropping the bolt on a round in the chamber, I put a round in the chamber and lower the bolt half way before letting go. I also do this with the rifle sort of level.

You will get DQ'd if your round lands in front of the firing line. I want whatever future AR slamfires I might have to hit the berm. Loosing 10 points is better than having to go home.

I also use CCI #41 primers as they have thick cups and are hard to pierce. These are excellent primers in the AR and I shoot HM scores (seldom HM standing scores anymore) all the way out to 600 yards with the things.

My recommendation, always feed rounds from the magazine to slow the bolt, if you drop a round in the chamber, lower the bolt half way before letting go.

Member Hummer70 says he's looked at the ammo every time there's been a slamfire at a match he's attended, and thus far has always found high primers among the shooter's remaining ammunition. So, high primers are most often the cause—just not always.

I don’t see how high primers can ignite unless the primer is seated in a shallow pocket. For a primer to ignite, the anvil has to be firmly set and the anvil/primer gap cup set. As CCI has said, and as many posts have shown, high primers are the most common cause of misfires. I am of the opinion the high primer cause is basically a red herring, a misdirection. One poster related in battery slamfires he had in a AR10. He had removed the crimp on military ammunition, but left the brass donuts in the bottom of the pocket. By putting spacers into his primer pockets, he created the conditions for a firmly set anvil and setting the anvil tip/primer cake gap.

Just to unsettle people, here is a list of slamfires, some out of battery, in rifles other than Garands, M1a’s, or AR15’s.


Slamfire in DPMS 308

http://www.thehighroad.org/showthread.php?t=467039

I had a slam fire once in my DPMS with regular primer reloads. I have since switched to mil spec primers or magnum primers for my auto rifle reloads. I also use the Lee factory crimp on all reloads for my autos. Kinda had to double up on supplies because I use bushing dies and match primers for my bolt guns in .308 and .223. I like to keep my brass separate too because I want to just neck size for the bolt guns and full size for the autos.

It was my .308. I was using some match primers because that was all I had at the time. I did fire up about 60 other rounds that day without incident.

http://m14forum.com/ammunition/101272-favorite-primer-m14-2.html

07-30-2011, 07:41 PM
hagar the horrible
Joined: Feb 2007
From: Columbia, SC
Posts: 291

I have never seen a slamfire with a Garand or M1A, but I have seen plenty with AR'15s, and in every single case it was a winchester primer, or the shooter did not know. I make it a point to ask. Had a friend in AZ that got a slamfire, no damage to the rifle, warned him about using winchester primers, and a couple of weeks later he got another one, this time damaging the rifle pretty bad. He switched to Remington 7.5's after that..

20 Feb 2008 Shotgun News,
Article “ Micro Galil, The Ultimate Krinkov”
Author Peter Kokalis
Page 12

“Most Kalashnikovs have inertia firing pins, without an associated spring. The initial lot of Galils brought into this country by Magnum Research INC. also had no firing pin springs. The Micro Galils that I examined in El Salvador were not equipped with spring-loaded firing pins either.

Military small arms ammunition primers usually have relatively hard cups, which are not easily touched off. American commercial cal .223 Rem ammunition, including Winchester ammunition often features fairly soft primer cups. In 1983, Winchester ammunition in particular caused several slam-fires and all Galils offered for sale in the United States were quickly retrofitted with strong firing pin strings. “

29 August 2007

CENTURY INTERNATIONAL ARMS, INC.
236 Bryce Boulevard
Fairfax, Vermont, U.S.A. 05454
Tel: (802) 527-1252 Fax: (802) 527-5631
Date: August 29, 2007
Subject: Galil and/or Golani Semi-Auto Sporter Rifle

We are requesting that customers who purchased the Galil and/or Golani Semi-Auto
Sporter that have serial numbers between GAL00001 and GAL02393 send in their
firearm to us as we have modified the bolt and are installing a new firing pin and firing
pin spring to ensure that your Golani offers you the utmost safety and reliability. All Galil
and/or Golani rifles that have the letter "F" or "X" on the bottom of the receiver front cut
off have already been upgraded and your rifle does not need to be sent in to us.If you
are a dealer, please provide us with the names, addresses and contact information of
the purchasers of these Galil/Golani rifles. We will contact them directly. If you are
contacted by these customers, please have them call us at 1-800-270-2767 to obtain a
return authorization. We appreciate your cooperation in this matter and hope to have
this situation resolved as quickly as possible




http://www.xdtalk.com/forums/ak-47-talk/89974-ak-slam-fire-question.html

AK slam fire question

11-05-2008 Hi guys

I thought I would throw this out there to see what you guys think might be causing a slam fire with my AK.

I took my Romy G to the local range to sight her in. I loaded up the mag with 3 rounds each time 40 rounds total. On two occasions after I fired the first shot the second went off right away. I can only describe this as a slam fire. It seems that when I fired a round something happened when chambering the new round and caused the second one to go off without pulling the trigger. I was using Winchester
White Box 7.62x39 (local range doesn’t allow wolf which is of course what I have plenty of)

11-10-2008

So I cleaned it all up and checked over the FCG real close and everything seems to be in working order. I am not getting the "hammer follow" issue. The disconnector is retaining the hammer when the trigger is fully depressed. And the trigger hook is is grabbing the front of the hammer.

I also took the bolt down and cleaned it up real nice.

I took it to the range over the weekend and put about 90 rounds of wolf down range and not a single issue. Nothing that resembled what happend when using the Winchseter ammo. I did check one of the rounds that were chambered to see if there were any marks on the primer and there was but it didnt go off.

http://www.thehighroad.org/showthread.php?p=6193244#post6193244

AK47 Saiga Slamfire

I have a Russian Saiga 7.62x39 That I love more than anything to shoot. The other day I took it and a few hand guns to the range (in door) The weekend before I picked up 700 rounds of the military ammo at the gun show Boy did I have a rude awakening. Slipped in a 30 round mag, dropped the bolt and un loaded 30 rounds without a miss fire. You have no idea how quiet it got there. I had the range officer on me so fast. After a lot of wounderment we found the problem. The primers in the military loads are soft. I have seen that happen in the SKS but never in an AK. I guess I wanted to share this adventure with everyone and a warning. With the range dude there I loaded up a 5 round with this ammo and it did it again. I then re loaded the 5 round mag with some Wolf 122gr. HP Steel Case and everything went back to normal. Just wanted to share this miss hap and be sure where your muzzle is pointing when you lock and load.

They came loose in a can which my brother has. I will contact him and tell you just what is was. I do think I remember that there were 500 Rounds military Surplus. Egyptian

http://www.canadiangunnutz.com/foru...ired?p=8841078&highlight=slamfire#post8841078

Very clean SKS that slamfired?
Hi all,

So picked up an SKS from wholesale the other week, stripped and cleaned the entire thing (including bolt), shot 20 rounds of PPV out of it the other day with no problem, cleaned it; then today I shot 10 rounds of federal ammo and had a slam fire on the last second clip. This was pretty scary for me because the FP was clean and moves freely in the bolt. Do you think it could be an issue with the ammo having sensitive primers?

http://www.thehighroad.org/showthread.php?p=7180249#post7180249

Browning Automatic Rifle (BAR) Slamfire in 270 Win. Neck sized cases.

It's good to think you had the good common horse sense to ask that question. Some have assumed nothing is any different since the cartridge is what it is, 30-06 or what ever high powered rifle round, and then necked it as with their bolt actions. A man came into the gun shot I worked in with a really nice, well was a really nice Browning semi auto, I think it was chambered in 270 win., no matter. He said he had been necking for a while for that rifle without problems. I doubt he considered now and then chambering issues as problems. Either way, all it took was one slam fire to ruin his day and rifle, and fortunately not his life!

http://www.thehighroad.org/showpost.php?p=6493506&postcount=4

Thread: Anybody know why "they"advise against .308 for M1A
View Single Post
Today, 09:48 AM #4

Hatterasguy
Member


Join Date: January 4, 2010
Posts: 670

I recently had a slamfire issue on my FN49 and I suspect it was casued by using commercial .308. I have yet to take it back to the range to confirm.
__________________
"Those who are allowed to shoot are those who are prepared to be shot."
Lelouch Vi Britannia

Out of Battery Slamfire in FN49

http://thefiringline.com/forums/showthread.php?t=543905

Hey all,
I recently had an 'out of battery slamfire' in my, two piece firing pin, FN49. I had made 8mm Mauser ammo from milsurp 30-06 cases. The dimensions of the cases (30-06 and 7.92x57mm S) are identical at the base and only need to be cut down to the correct length, sized and trimmed. The problem with making your own ammo for the FN49 is that it is a very robust firing mechanism that will ignite a sensitive primer before the round is seated in the chamber. I was using CCI 200 Large Rifle Primers which are reasonably sensitive for bolt action rifles and, I have found out, too sensitive for semi auto rifles. Even though I've used these primers for years in my FALs, and WASR AK47, I'm going to stop and use CCI 34 Large, 41 Small, or milsurp in the semi auto rifles.

The 'oob' slamfire caused the receiver and bolt carrier to become a bad fit! I searched (Google) and found a gunsmith in Missouri who could fix the rifle. His name is Guy Snelen at AMG International in Humansville, Missouri. He repaired it, test fired it, and sent it home to me. If anyone needs a good gunsmith, get in touch with Guy.

Kaboomed 8mm Egyptian FN-49 .... Now A Floorlamp!!!!

http://www.sksboards.com/smf/index.php?topic=132165.0
« on: July 03, 2014, 06:26:50 PM »

My LGS gave me this Kaboomed Egyptian FN-49 today. It's a CAI gun. To add insult to injury it was the second time it had kaboomed. The owner had it "fixed" and then it let loose again after a few rounds. I think I would have quit the first go-round.

The funny thing is when I took it apart I could not find any reason it let go unless it fired out of battery. The gas setting was fine. The only broken part was the rear of the extractor when the kaboom bent it out and cracked it.

When it let go (8mm Romanian surplus) it looks like all the force went straight down and bulged the mag and in turn stretched the sides of the mag well in the trigger group/guard assembly. I got the mag pounded back in shape and bent in the sides of the mag well opening true.

One thing I did notice was that the stock was repaired poorly after it let loose the first time. It would not have taken but a few rounds to have split it again. It is one of those beech CAI replacement stocks and it split darn near perfectly in half.

I could fix the stock but why bother, I'd never-ever trust the rifle. The guy got away twice with nothing but hurt feel-goods and a lighter wallet and I don't want to be the odd man out with a injury.

I was thinking of parting it out or selling it as is but I think I might make a gun lamp out of it instead to preclude anyone getting bad parts or crazy ideas of trying to shoot it.

I glued/screwed the stock back together well enough to start making a lamp of it. It will be real easy to do.

http://www.thehighroad.org/showthread.php?t=665024&highlight=French+7.5+Bullet+Diameter+info+Request

http://web.archive.org/web/20060506045913/http://members.nuvox.net/~on.melchar/75french/sainfo.html

These articles were available on-line, but the links are dead, so I copied
my post from an other board (two posts here as we are limited to 20000 characters):

Disclaimer: This article contains information that may not be appropriate for your particular firearm. Consult your gunsmith in regards to the safety of firing your particular firearm. Consult your reloading manuals for all safety procedures when reloading ammunition. We are not responsible for typographic errors. Your mileage may vary.

What follows is a reproduction of an article from Handloading Magazine on the 7.5x54 MAS, prefaced with comments by myself, updating the magazine article with considerations for the MAS semi-auto rifles.

Update: Reloading the 7.5x54 MAS.
By Paul Pelfrey

While the reprinted article that follows is essentially accurate, the author did not take into consideration the availability of the various semi-auto French rifles that would later be on the market at an affordable price. This article should be applicable to the MAS-44, MAS-49 and the recently imported MAS-49/56 rifles. With the data in table II of the article below, I didn’t need to reinvent the wheel to start my experimentation. My load was the 150 grain Sierra FMJ spitzer, loaded on Norma brass, with Winchester WLR primers, packed with 44 grains of AA-2520 powder. I had had a good experience with this load through my MAS-36 bolt action rifle and decided to give it a go in the MAS-49/56. The MAS-49/56 I had acquired came from SOG and was still in the arsenal wrapping when I received it. After a thorough cleaning I took it and 50 rounds of my handloads. I first test fired the rifle with some surplus Syrian ammo I had. I was disappointed. The Syrian ammo was rife with hangfires and dead primers, and those rounds that did fire would not actuate the bolt properly. Most of the rounds stovepiped none ejected fully. I then took my handloads, loading a single round in the magazine at a time and easing the bolt forward. To my delight, the rounds were rather accurate, keeping inside 1.5 inches at 50 yards, and the brass ejected cleanly. After 10 shots loaded one at a time I loaded two rounds. This time, I let the bolt fly forward on it's own to chamber the first round. The round immediately slamfired as the bolt closed, and the second round chambered. My finger had been outside the trigger guard. I unloaded the gun, then reloaded two rounds. This time, the round did not fire when chambered. However, when I pulled the trigger, the rifle fired both rounds in rapid succession. My first thought was that this was a repeat of a phenomenon that I had experienced with an SKS carbine. In that case, the modern lube I had used on the SKS was too slippery and allowed the firing pin to travel forward with the bolt actuation with sufficient inertia to impact and detonate the primer. In that case, removal of the lubrication solved the problem. I disassembled the MAS rifle and dried the components completely and reassembled it. The slamfire problem persisted. My attention turned to the handloads. Checking the primer seating depth and dimensions of the case turned up nothing out of spec (except the smaller rim diameter, per the Handloader article). I then chambered a Syrian round and then removed it. Examining the Syrian round showed a slight indentation on the primer. I then left the range to ponder my next move.

Next weekend I returned with more handloads, this time using CCI regular and match primers, and Remington primers. During this session my handloads still suffered from slamfires while the military French and Syrian ammo did not. Conclusion: Commercial primers are too thin to operate safely in the French MAS semi-auto rifles.

Solution: CCI, under the name of their parent company, Blount, manufactures a military spec primer. I found a brick at a gunshow in a plain white box. The label read "1000 M-34 Primer for 7.62mm Cartridge". Loading 50 more rounds with these primers solved the problem. Not a single slamfire. Most distributors do not carry this primer, and will only order and sell it in a case lot (5000 primers). The good news is that these primers sell for only about $6-$9 more than the same quantity of regular primers. I would recommend their use in any round that might be loaded in a semi-auto rifle, just for an added margin of safety.

Reloading this round has become much cheaper since the publication of the Handloader article. Lee now makes the dies for this round, and I have seen a retail store price on them for $29.99 (half of RCBS). After talking to the techs at Lee, they are willing to make a tapered expander for necking up the Swedish brass for $15, and if you send them a formed cased with a bullet (no primer, no powder) they will make one of their Factory Crimp Dies for it for $25. I recommend this, inasmuch as a few of my handloads had a problem with the bullets being pushed back into the case upon chambering. This can lead to overpressure and possible injury. Brass is more plentiful now as well. I find Remington 6.5 Swedish at shows for $27/100 and Kengs in Georgia also stocks Lapua 6.5 Swedish for a similar price.

.


http://thefiringline.com/forums/showthread.php?t=425509&page=2

Tamara
Moderator Emeritus

Join Date: March 11, 2000
Location: Indianapolis, IN
Posts: 15,880

Originally Posted by B. Lahey

The Prvi was the only ammo I could find, and it seems to get good reviews from MAS 49/56 owners, but I also found one complaint of a slam-fire with it.
The MAS-49 has a massive firing pin to make sure it pops hard military primers. Slamfires are not uncommon with commercial Prvi or FNM ammo. Mine gave Oleg Volk a pretty spectacular bruise on his right thumb with the bolt handle when he chambered a round.

Titanium firing pins were available for a time, but I haven't seen any for a while. Others have reported success in lightening the original FP.

I'd put one round in the mag the first time you let the bolt fly, just in case...
__________________
MOLON LABE!

I don't know a single semi auto rifle design with a captive firing pin. Pistol mechanisms have firing pin blocks, don't know of a rifle with one. Therefore all semi auto mechanisms have free floating firing pins. Because of this, it is my opinion, you want to use the least sensitive primer you can. Commercial primers have gotten ultra sensitive because shooters complain about the round not going off. You find lots of threads on this, and what is blamed, is not the ancient mainsprings in the boom stick, but the primer. Sometimes the ignition mechanism is so inadequate that certain brands of commercial primers won’t ignite, which leads to that manufacturer reacting to the market by making their primers more sensitive. Just before 2000, Winchester made their primer more sensitive, including their rifle primers.

To hammer on the ideologues at the CMP, they are preaching that only high primers and your worn out receiver bridge cause slamfires. They will not and do not acknowledge that the root cause for 99.99% of slamfires is a sensitive primer whacked by a free floating firing pin. Decades previous, the Army and the NRA claimed the only causes of slamfires were high primers and worn receiver bridges and that is nonsense. These guys are so out of touch with reality, they probably believe the nonsense they preach. If you really look at what they are preaching, the only causes of slamfires are shooter misconduct, they totally ignore the action design. In their delusional universe the Garand mechanism is perfect. Well it is not and was not. The only semi auto’s on the firing line decades ago (in quantity) were Garands and M1a’s, so shooters did not have a basis of comparison with other mechanisms. Look at the reports of slamfires in other mechanisms, mechanisms that are totally different from the Garand, no receiver bridge for one thing, any yet, they slamfire with factory ammunition. Which, presumably, won’t have high primers. There are plenty of accounts of slamfires in mechanisms where the reloader explicitly said the primers were below the case head.

If the high primer only theory is correct, then neck sizing is fine for semi auto rifles. So is using the most sensitive primers, like pistol primers for cast bullet loads. There are probably some other dangerous practices that fall out, and have hurt shooters, destroyed rifles, because of the lies of these types.

 

[schmellba99]

Technically that's correct. It's true for every round you fire in any gun, though, at least in some small degree.

I understand that, trust me I do.

My post was made a lot more tongue-in-cheek with respect that there are times, and members, that seem to go overboard on some things regarding reloading.

For example - on this thread, if I were a newbie getting into reloading for the Garand I found in Grampa's closet, I'd read slamfire's post and then say "eff it, no way am I going to reload for this rifle because I"m not going to spend that much time and effort on tools, precision equipment, custom cut chamber gauges that I need to measure every round, electron microscope scanners to verify that my primers are seated perfectly at .000728874" below the face of the case head, etc. etc. etc."

Just like reading (or attempting to discern what is being said anyway) in one of F. Guffey's posts - if I were getting into the reloading world and used him as a guide for what needs to be done, I'd quit before I started simply because not every single person needs to know what the bore diameter is of his rifle barrel at 7.9927847220984" away from the end of the chamber is, or what the land diameter is so that we can custom cut our own dies and turn our own projectile to be within .0000001" of land diameter so that we may have a chance at having a proper projectile to bore fit and hope we may be able to squeeze some type of acceptable accuracy out of that particular rifle.

Same with the tube fed primer thread.

There are just times and subjects that get so far off into the twilight zone of the 1:50,000 chance something may happen that it begins to become comical, and honestly I think counter productive to conveying good information. And sometimes posters just have to be "right", come hell or high water.

I think slamfire, to use this thread as an example, posted good information about something to keep in the back of your mind when loading for a Garand or M1A (or the 32 other types of rifles he posted slamfires about), don't get me wrong. But anybody looking for practical information on reloading for a Garand is likely to be absolutely paranoid of doing so after reading his posts.

We all know shooting and reloading is not without peril; it is inherent due to the very nature of the mechanical equipment an chemical reactions necessary to send that projectile down the barrel at 3k feet per second. No need to overplay the danger, IMO.

 

[mehavey]

Slamfire's post (as he intended):
~~~~~ DISPELL BAD INFO -- IDENTIFY DISCIPLINE/SOLUTIONS ~~~~~

- There are out-off battery slamfires in the Garand design (both M1 and M1A)

- These slamfires are primer related (both in seating and in sensitivity)

- These slamfires are exacerbated by (a) case resistance to freely seating on closure, and (b) free-bolt speed in the absence of resistance from stripping a magazine round.



Like anything else in life, these three things can be mitigated against very effectively:

- SB size the cases (insurance)
- Use CCI/mil-spec primers (insurance)
- Hand prime to ensure proper seating (discipline)
- Don't let the bolt freely slam home on an already-seating cartridge (discipline)

Simple.

 

[1stmar]

I agree. I am certainly revisiting my reloading techniques for my garands and M1A. I feel as though I have been lucky to not have had a slamfire.

If you go back and look at the history of the M16, there were countless reports of issues with the first model's hence the forward assist etc.. I am surprised that I have never heard of slamfires being a chronic concerns for M1's in combat, given the extreme opportunity I would have thought there would have been more awareness or enhancements to address.

 

[Unclenick]

I don’t see how high primers can ignite unless the primer is seated in a shallow pocket.

I think it's probably a complex dynamic interaction. A high primer in a revolver or a bolt rifle pretty much only has the firing pin pushing forward on it. In the Garand and M14 mechanisms, the case shoulder get shoved pretty hard forward by the extractor so I expect it rebounds some when the extractor snaps past the rim and into the extractor groove of the case. You then end up with a poorly supported primer that is more deeply indented by the firing pin than would be the case with a properly seated primer, and then the case rebounding against the bolt face and tending to seat the primer at least flush with the head and perhaps shoving the anvil reward before the firing pin bounces back as well. This is just speculation on my part, but assuming the pattern Hummer70 has observed is a valid one, I expect some dynamic like that is involved.

The CCI #41, CCI told me ove the phone, is identical to the CCI 450 in both cup and priming mix, except they use wider angle anvil legs to achieve the military sensitivity numbers. Federal, on the other hand, has their new (relatively) GMM205MAR, which they told me by email is identical to the 205M except that in their case they did make the cup thicker to get it down to military sensitivity spec.


Schmellba99,

An issue has been a number of persons (the CMP bulletin board, in particular, seems to attract them) who just flatly deny any problem like an OOB fire can ever happen in a Garand under any circumstance because they, personally, don't see how it could happen. And they seem to make a point of telling every newbie so and contradicting good advice to minimize the chance of it occurring. These individuals take advantage of the fact these events are rare enough that they can get away with spreading misinformation about them and not see too many people disagree with them.

As I explained, the amount of luck you need to avoid the issues described is not huge. Many have gotten away with being sloppy in their loading practices. And for myself, I'm not overly concerned about the personal risk but feel obliged not to subject the fellow on the next firing point to even a small risk I can so easily mitigate. It's just a matter of the usual warnings not to treat handloading in a cavalier fashion by taking on some extra weight and some extra considerations in floating firing pin self-loaders.

 

[schmellba99]

feel obliged not to subject the fellow on the next firing point to even a small risk I can so easily mitigate. It's just a matter of the usual warnings not to treat handloading in a cavalier fashion taking on some extra weight and some extra considerations in floating firing pin self-loaders.

Nothing wrong with that at all - we pretty much do that on every thread in one form or fashion as it is.

But there is a bit of a difference between mentioning a particular action could possibly happen (in this case, a slam fire) and writing a dissertation that essentially states that if you don't have these specific tools and do these specific things and ensure that these specific measurements are adhered to, you'll have a slam fire with your gun and it will be all your fault.

I'd like to think that anybody with an nth of common sense would realize that with any semi-auto weapon, slam fires are a distinct possibility - whether from the gun or the ammo. Seems inherent that the possibility is there to me because of the very nature of the operation.

 

[Slamfire]

Slamfire's post (as he intended):
~~~~~ DISPELL BAD INFO -- IDENTIFY DISCIPLINE/SOLUTIONS ~~~~~

- There are out-off battery slamfires in the Garand design (both M1 and M1A)

- These slamfires are primer related (both in seating and in sensitivity)

- These slamfires are exacerbated by (a) case resistance to freely seating on closure, and (b) free-bolt speed in the absence of resistance from stripping a magazine round.

Like anything else in life, these three things can be mitigated against very effectively:

- SB size the cases (insurance)
- Use CCI/mil-spec primers (insurance)
- Hand prime to ensure proper seating (discipline)
- Don't let the bolt freely slam home on an already-seating cartridge (discipline)

I like it! Much more concise than my ranting and raving.

If you go back and look at the history of the M16, there were countless reports of issues with the first model's hence the forward assist etc.. I am surprised that I have never heard of slamfires being a chronic concerns for M1's in combat, given the extreme opportunity I would have thought there would have been more awareness or enhancements to address.

A history lesson of a sort, the early M1 Garand had a round firing pin exactly like the round M1 carbine firing pin. These are pictures of the rare early round firing pins, when Orion 7 had them, they sold out their inventory at $100.00 apiece!






It is obvious the Army experienced slamfires in early Garands because later firing pins were scalloped to reduce weight. On top is the Garand firing pin, the middle the M14, and the bottom a M1 Carbine firing pin.




Since this was so long ago, and there are no records, we don't know all that went on behind the scenes. As the Army did for the M16, they could have made the primer less sensitive, but they could not have made it too insensitive because that would have caused misfires in other mechanisms which used the 30-06 cartridge. The simplest solution was to reduce the kinetic impact energy of the Garand firing pin by reducing its weight. Which is something that was also done for the M16. This was not necessary for the M1 carbine, so they kept the relatively simple to make but heavy, round firing pin. To accommodate this heavy firing pin, the M1 carbine primer spec is a very insensitive primer.

The history of the #41 primer is different and came about due to slamfires in the early M16’s.


http://www.dtic.mil/dtic/

Report of the M16 Rifle Review Panel. Volume 5, Appendix 4. Ammunition Development Program

Primer Sensitivity

Initial Specifications. Ammunition specifications established by the Air Force on 24 January 1963 provided for quality control against cocked, inverted, loose, and nicked primers. The specifications further provided for inspection and test of waterproofing and the crimp of primers. However, the specifications did not provide for specific limitations on primer sensitivity for 5.56mm ammunition.-

Development. At the first meeting of the Technical Coordinating Committee on 26 March 1963,16 / the Air Force representatives submitted a list of reported ammunition deficiencies, which included "high primers" and "primers too sensitive". It was agreed that Frankford Arsenal would investigate the matter and recommend corrective action.

One of the malfunctions reported by the Air Force was the premature firing of cartridges that occurred upon initial charging of the M16 rifle with a cartridge from the magazine, or upon singleloading of a cartridge directly into the chamber, or when two rounds were fired at one trigger pull during semiautomatic fire.

This malfunction was attributed to "high" or protruding primers, although the tests did not confirm this theory..

However, analysis indicates that if high primers caused the premature firing, the firing should have occurred upon impact of the bolt face with the protruding primer. At this point in the weapon cycle, the bolt head would not. have been rotated to the locked position by action of the cam pin and carrier. Had firing occurred with the bolt in the unlocked position, it would have resulted in a blow back and would not have been undetected. No such disruptions were reported-. Since premature firing occurred after bolt-locking, it must have coincided in time with the impact of the bolt carrier against the bolt head. At the instant of impact, the "free floating" firing pin is moving at the velocity of the bolt carrier. The kinetic energy of the pin must be dissipated by such frictional forces as it encounters in the forward movement, and, finally, in impact of the firing pin tip with the primer of the chambered cartridge. This premise was confirmed by the visible indentation appearing on cartridges which were chambered by the mechanism and extracted unfired.

Frankford Arsenal identified test procedures for measuring firing pin energy and recommended limits for primer sensitivity.

Remington Arms Company, on the basis of the information contained in the Frankford Arsenal First Memo Report, undertook the design of a new primer that would be less sensitive and less susceptible to the inadvertent energy delivered to the primer by the free-floating firing pin of the AR15 rifle. Since it is difficult to adjust primer sensitivity by chemical changes, Remington elected to accomplish the desensitization" by increasing the mechanical strength of the brass primer cup, which must be indented by the firing pin to cause ignition.

As a result of the decision of the Commanding General, USAIIC, to modify the rifle, Colt's Inc. developed two designs, a linear spring device and a cam pin friction device, to reduce firing pin energy on bolt closure. These two designs were tested by the Air Force conclusions of this test were that both devices effectively reduced firing pin energy; however, the Air Force recommended against their adoption because they increased the probability of a misfire (although no failures to fire were identified in the test results), added to the cost of the weapon, and adversely affected its reliability. Army tests of these devices indicated that the linear - ~spring friction device was a satisfactory solution; however, at the Technical Coordinating Committee meeting of 10 December 1963, at which a comparison of all tests done by the Army, Air Force, and Colt's Inc. was made, the committee agreed to adopt a modified lighter firing pin, which was used in the cam friction device and was recommended by Colt's as a solution to the problem..​

So, to reduce slamfire rates in the M16 the Army did two things: 1) it reduced firing pin weight, and 2) required the use of less sensitive primer, the #41 primer.



The heavy original M16 firing pin on top.

 

[Jimro]

Funny you should mention the M16.

For a floating firing pin to impact a primer before the bolt is in an in battery position on the M16, or for the M1/M1A for that matter, the extractor has to snap over the rim of the cartridge.

Then either the firing pin has to be jammed forward by gunk, or have enough inertia to set off the primer.

The M16 bolt design being what it is, makes it impossible to have the firing pin protrude without the bolt being cammed inside the bolt carrier group, which is something the M1/M1A does not have. In the M16 the shoulder at the rear of the firing pin stops against the BCG until the bolt is pushed back and cammed over so that the end of the bolt is what stops forward movement of the pin.

For an M16 to have a total out of battery slam fire, the bolt can't get bound up in the "star chamber" area, it has to be fully in or fully out, but fully out can be tricky because the cam pin binds against the inner surface of the upper receiver.

So all this leads me to believe that the slamfire events for the original M16s leading to the adoption of the #41 primer were in battery slam fires.

Jimro

 

[Slamfire]

So all this leads me to believe that the slamfire events for the original M16s leading to the adoption of the #41 primer were in battery slam fires.

I believe that all the M16 slamfires were in battery, but there is no data of the incidents to know what exactly happened.

This is interesting from a historical perspective:

Icord report page 4560
Mr. Stoner. Well, yes, because I knew that the rifle was, you know, was going to be used by the armed service and I wanted to make sure that we had adequate background on it before we went into it. Because the history, and all the testing that was done with the IMR propellants. We had another thing that happened on the Marine Corps test that went with that. We had some inadvertent firings of the weapon due to the primer that we were using. We were using a commercial primer in that round which is relatively soft and sensitive, and the Marines, on their firing, on their known distance range, would single load the weapon. They would put a round in the chamber and then let the bolt go home by pushing the closing button on it or the bolt catch, and the inertia of the firing pin would fire the weapon sometimes this way.

It was a very low frequency, but it did happen. So, of course, they wanted something done about it, and the Army found out about this. There were a couple of solutions. Either desensitize the primer, make it out of a thick material, or lighten up the firing pin. Well, what I recommended was lightening up the firing pin because I didn’t see-if you desensitized the primer too much it could cause failures to fire in the field.

In other words, we wouldn’t have enough energy to fire the primer under all conditions. And I-in this technical data package they decreased the sensitivity of the primer at the same them they went in and put the ball propellant in. So these were two things I objected to with Mr. Vee.

Here again, I didn’t know what the effects would be because we didn’t have all this test data, I mean testing, behind us that we had on the other ammunition. While the design on the firing pin, to lighten it, which was subsequently done by Colt, was a relatively simple thing, and in my opinion, wouldn’t detract from the performance of the weapon any. As I say this weapon was tested for years and years and before this inadvertent firing ever come up and it come up because probably we had a batch of ammunition where the sensitivity level on these primers were on the low end, or, I should say, the high end of sensitivity, and also, the fact that there were firing the weapon in a way that they formerly didn’t before, which was single loading, when it was an automatic weapon.

Usually the weapon was loaded from the magazine and when the rounds were stripped out of the magazine like it was intended to be used, this slowed the bolt down enough that you didn’t have the impact velocity to cause an inadvertent firing.

There were actually two things that I took exception to on that. I didn’t sit in on the Board that came up with the ammunition specification. I wasn’t asked to. I am not in the ammunition business. But, I have a good deal of interest in the ammunition due to the fact- usually you can’t change the ammunition without causing a change in the performance of the weapon.

Besides verifying that the early M16's slamfired, what Stoner claims is the real problem, that the USMC was not using the weapon properly, because they were not always firing from the magazine, is in fact, pure hogwash. The M16 procurement revealed that the Armalite and Colt Organizations did little in examining the technical performance issues of their rifle. As this testimony shows, Stoner only knows about primer sensitivity as a concept. He does not know how much energy is required to ignite an average primer, and he does not know the kinetic energy of his firing pin. It turns out, if you study this, the kinetic energy of his early firing pin was always above the "none fire" limits of commercial primers. None fire is a very important safety criteria: no primer is supposed to ignite when hit by a firing pin whose kinetic energy is less than the "none fire" limit. Stoner's design, the primers were always being hit by a firing pin whose kinetic energy exceeded the "none fire" limit.

Stoner does not accept any responsibility in this. He does not know what he does not know, and he does not know the numbers behind primer sensitivity. Stoner considers his design perfect. It was far from perfect, it was in fact an immature design that was not ready for combat.