45 reloads blowback

polyphemus,

Your suggestion noted above to use an adjustable charge bar is not the only simple and safe solution that could work for the OP. You dismissing drilling a disk as unsafe out of hand confuses me and please do not infer that I am telling the OP to disregard all known safety protocols in reloading by doing so.

No one said the idea of screwing a cavity was new. Your use of the phrase 'pointedly doesn't in the second' is a spinning the mere change in text, and adding an adjective that doesn't belong.

The first edition has a paragraph introducing the Lee adjustable charge bar that states "A customer suggested a novel modification. Addition of a set screw from the outside of the diameter...... be sure to use cone pointed set screws.....".

The second edition introduces the adjustable charge bar with a statement regarding a 'desire for loads falling in between the existing cavities' and notes "At least two other companies made after market accessories to replace the disk." And further notes that Lee has a low cost alternative and better solution via the adjustable charge bar.

IMO the set screw omission was done merely to focus on selling their charge bar. IMO if Richard Lee thought there was a big danger in drilling a disk he would have noted such (ala the discussions about Federal primer sensitivity and change over to the new XR hand primer).

I would imagine the OP, even though he is new here, has enough knowledge to measure powder and ensure consistency from whatever method he chooses to address his goal. Everything in reloading is about learning and using caution with the knowledge gained here and from others. Given that, the risks consist of messing up a disk cavity and learning along the way.

OP, sorry for the momentary highjack. polyphemus, please continue to enjoy your own opinions and experiences along with offering your 'number of other simple and safe solutions'.
 
No,you are the one one talking about risks.
And by the way highjacking the thread.Stick to the issues and the question
and try if you can to offer first hand advice,if you have evidence of such modification and how it worked for you then post it.
 
Unless you really are shooting at the very top end of accuracy in competition and you know that x.x gn is really the BEST load, I see no reason to NOT go up to the next cavity and be done with it.
Even better, if the load shoots fine, is to STOP being concerned about soot on the case.
For the number of times this "issue" comes up, there should just be a sticky that says: "low pressure, light load, ignore or increase charge" and we can all reference it.
 
Oh how I am discouraged by someone trying to say that my remarks about risking messing up a disk by simply drilling it are somehow related to risks to safety in life, limb and firearms, which is simply not true. Drilling a disk and using a set screw is not a safety issue if you follow all known reloading protocols.

As I indicated above, I read the thread I referenced for the purpose of hopefully being able to reduce the charge thrown by a particular cavity. I had great success, based on a little time study and deciding how to go about it.

This might help the OP, if he so chooses to try. But trying other powders and a drum measure might do so as well.

Over two years ago I started loading Frontier brand 230g RN plated bullets for my 45 ACPs in both a SW1911 and SW4506. In working up the load, using Universal powder, I found that the .53 disk consistently dropped 4.8g(+/-.1), the .57 disk consistently dropped 5.2g (+/-.1). The .61 disk consistently dropped 5.6g(+/-.1).

The Hodgdon website recommends a range of 4.5 to 5.4 for RNL and then 5.1 to 5.6 for the Hornady 230g FMJ FP. Knowing that plated bullets should be loaded less than FMJ, study this on your own time, I wanted something less than max load.

In working up the load on these plated bullets, I wanted to move up closer to the 5.4 max for RNL bullets as listed on the Hogdon website, but not go over, as the 5.6g max for the FMJ. The 5.6g was slightly snappy for second shots and I don't want to beat my guns more than necessary or strip plated bullets.

Thus the exploration for adjustability of the disks. See the pictures below to see what worked for me. This unit throws 5.4g (+/-.1). (Hint, please feel free to use the website tineye.com to do a reverse search to see if you can find these pictures anywhere else.) Make sure you note how much the screw 'obstructs' the powder drop.

This unit was assembled with a knowledge of socket head cap screws, using a drill press, a tap set, a file, and a sharpie. I will direct you youtube if you need help with that. I can post pictures of contemporaneous notes if anyone wants to be bored to tears with the obvious.

I was successful in this endeavor for this goal. The OP might be able to check to see if reducing volume in the larger cavity gets him the slightly cleaner cases he desires. Or he might choose to do something else entirely.

polyphemus, you remark "OP has a minor issue and there are a number of simple and safe solutions to resolve it". I offered alternatives beyond screwing a disk in post #19. Why don't you offer your safer alternatives with some pictures of their success or perhaps document how your personal attempt at drilling and tapping a disk was not successful and the poor results you encountered. I am anxiously awaiting to learn from your documented experiences.


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+1 to you noylj on a very good point. Truly the sooty case issue can be chased to the end of days when the easy solution is an extra hour in the tumbler and an extra patch down the barrel.:cool:
 
More pressure will fix your soot issue, but more pressure will make more recoil. The other option is a faster burning powder like Clays, Bullseye, Titegroup...

Something to consider....what problem does this soot create?

As far as crimp goes, IMO, it's purpose in pistol rounds is to prevent setback. So, I setup crimp by:

Back off your Seater Die crimp to 0. Set the right OAL in the seater. Then adjust the internal taper crimp to remove all flare. Check with a straight edge.

Then I set my taper crimp die to touch off on the case. Then in 1/4 turns I adjust until I get minimal setback when seating the round 5 times by dropping the slide. I drop the slide 5 times on each round measuring OAL each time. I find 1/2 turn crimp is the best condition. I also find that with Hornady's new die sets that the separate crimp die may become less valuable as it is easy to dial in on the Hornady seat/crimp die.
 
It's funny this thread comes up right now . I've been loading rifle cartridges for awhile now but just started loading pistol about a year ago . Pistol powders have been real hard to come by in my area . The only ones I can get are the slower ones like Auto comp , HS-6 , Longshot , CFE pistol & WSF .

I'm loading 9mm 115gr and 124gr as well as 45acp 200gr and 230gr . Every single one of those powders leave scorched and sooty cases . I've been very disappointed in this . I had great hope for CFE but in 45 I get soot down to the extractor groove with 200gr JHP . I tried it with 115gr PLRN in 9mm and also got pretty sooty cases . The 9mm loads how ever were very accurate . Maybe my most accurate to date .

So I've been feeling that sooty cases is bad and I still need to find better powders for the calibers . How ever it seems many here are saying don't worry about the scorched cases . If it goes bang and is accurate , there's very little to complain about . Is that an accurate summary of sooty cases ?

I have some titegroup that does not leave any soot on my 115gr 9mm loads at 4.6gr @ COAL 1.110 . I'm going to try it with the 200gr 45's but not the 230gr bullets .

I guess I'm just thinking out load here but I don't want sooty scorched cases but it appears you all don't think it's a big deal ?? Isn't all that blow back scorching the chamber just as much as the cases ? Well more right because the cases only experience the blow back once each while the chamber gets it every time the gun is fired . Any chance that starts etching the chamber or results in some hard carbon fouling build up in the chamber ?? .

I'm not a hand gun guy really . I enjoy shooting them but nothing like shooting rifles at hundreds of yards . So I don't ever shoot a lot per trip . The most is about 300 rounds per hand gun . If I get around the 300rd mark I'll likely clean after but anything under 200rds and I likely won't clean the firearm . My point , It is very possible any one of my hand guns could see 500rds before cleaning .

Now if those were all pretty dirty firing rounds would I be putting extra stress on the chamber do to scorching or carbon fouling ??

I'm asking because I have some good loads as far as accuracy goes using those slow-ish powders but MAN they're dirty :(
 
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If you look at a revolver cylinder you will notice the throat is made from the same chunk of metal the cylinder is. The throat takes the full brunt of the powder burn without damage. A little gas blowing back around the case is not going to hurt the chamber. The same is true with almost all self-loading pistols. The chamber and barrel are all one piece of metal. A little blow-by soot isn't hurting anything.

If it was an issue, you wouldn't be able to shoot .38spcl in a .357mag, etc.

Another issue which I believe has already been mentioned is the autoloader may be unlocking and starting to yank the brass out of the chamber after the bullet has left the barrel, but before all the combustion products have cleared out.
 
The statement about revolvers is true. It takes maybe thousands of rounds through a rifle, at 6,000 or so pressure levels, 3,000 fps, maybe 50 grains of powder to wear out the throat of a rifle. That is an intense blast that is exponential to the mild pop of a pistol, which sometimes doesn't even manage to properly expand the brass.

I find that the brass comes clean in my tumbler. The carbon will clean up.

HS6 is one of the old school ball powders that is genuinely great for nine. Great velocity with moderate pressure. For powerful loads without going the full extent of to the limit thinking, I use AA5 for .38, HS6 for nine. I don't really believe that either powder was particularly dirty at healthy loads. Even f factory ammo comes out dirty sometimes in my experience.

I suggest that you worry less about whether you wind up replacing a barrel in the future.
 
Great points there guys and if I would have put just a tad more thought to it . Maybe I would have came to that very logical conclusion :o .

Thanks
 
head space

I found out that 45 acp does not head space off the case mouth,it is held back with the extractor.check out the Fat Book on the 45acp by Patric Sweeney.
 
I found out that 45 acp does not head space off the case mouth,it is held back with the extractor.check out the Fat Book on the 45acp by Patric Sweeney.
Click to expand...

I think one needs to understand what head space is before making statements like that . Head space is a set dimension of a chamber . The extractor , ejector or bullet have nothing to do with it . If you place a 22lr round in a 45 and was able to get the extractor to hold it in place . That firearm would still have the exact same head space as it did before .

I'm 100% sure the 45acp DOES NOT head space off the extractor . That does not mean the extractor will not hold back short cases from reaching that step in the chamber the cases mouth head spaces off of . Just because an extractor holds back a case against the bolt face resulting in stopping the case from moving fully forward . That does not change head space .

I can size a 308 case short enough that the extractor will keep the cases shoulder from contacting the chambers shoulder . That does not mean 308's don't head space off the shoulder . It just mean I don't understand how to reload .
 
You misread that book. The acp case does headspace on the case mouth. The brass edge of the shell mouth is supposed to be in count with the end of the chamber mouth to base, the shell should be 22.81 mm. Slide and barrel should meet with just a few thousandth inches of space between breech block and the base of the properly sized cartridge. Base.

The extractor has nothing at all to do with holding it in place, just like almost all standard firearm designs, all it does is hang onto whatever rim the cartridge uses, and pull it out of the chamber.

If you want, someone can surely post some references.
 
I found out that 45 acp does not head space off the case mouth,it is held back with the extractor.check out the Fat Book on the 45acp by Patric Sweeney
Click to expand...
This above has nothing to do with OP's issue.
Then,that is not what Mr. Sweeney says "The 1911 [probably] uses the extractor to wrangle the case into position well enough for the firing pin to strike it." Probably and that when tolerances cause the cartridge to fall short of the intended design which is headspacing on the cartridge's mouth.
 
One of our professional gunsmiths said he estimated that almost 70% of the 1911's he'd seen over the years were actually "headspacing" on the extractor hook. Browning intended it to headspace on the case mouth, but the loose tolerances of many guns have caused many extractor hooks to catch the rim before the case mouth reaches the end of the chamber.

This is especially so with reloads. The 45 Auto doesn't have enough pressure to stick to the chamber during firing, so the whole case backs up during firing, filling out the taper in the chamber, then having the brass flowed rearward during resizing. This causes 45 Auto brass to shrink during each load cycle, rather than grow, like a rifle case does. I once tracked some bulk Winchester brass through 50 reloading cycles with light target loads. By the end about 2/3 had either split or been lost to the range gods, but enough were left to measure that they had lost about half a thousandth per load cycle and were all in the ballpark of about 0.870" long, having started out at about 0.895". There's no way they could get past the extractor to find the end of the chamber at that length.

"Headspacing" on the extractor hook does not seem to affect the performance of jacketed bullets as long as the extractor hook doesn't break (it is, however, a common replacement part). They are tough enough that when the case pivots on the extractor hook toward the right side of the chamber, they can straighten themselves out without deforming. Lead bullets are another story. They tend to swage into the chamber at the tilted angle, and that causes imbalance that opens groups up and the shaving increases leading in the bore. I figured out long ago that if you seat lead bullets out to touch the throat before the case rim reaches the extractor, thereby headspacing on the bullet, groups would shrink by as much as 40% and leading was reduced substantially (third image from left, below, as I showed in my previous post in this thread).

45SeatingPossibilities_zpsea6ec64c.gif


Headspace is technically a characteristic of the chamber. It's the length from the breech of the gun to the cartridge seating surface in the chamber that stops it from going further forward. The extractor hook is not part of the chamber, so I put "headspace" in quotes to describe the cartridge stopping against it. The rifling throat can be argued to be part of the chamber since the same reamer cuts it and the freebore affects pressures, so I don't bother with the quotes there.

Incidentally, a lot of the old time target shooters not only let the bullets stick out to find the throat, they would then roll crimp the case mouth into their bullets to increase start pressure and always claimed that produced the best accuracy, even if it did shorten case life. Obviously the rolled crimp doesn't meet SAAMI case mouth dimensions, but it doesn't need to with the bullet stopping the cartridge.
 
In, nicely detailed and obviously correct post. The most important things that I've gleaned from all of the answers.

By design, the case should stretch for breech to chamber. If not, a short case.will still be held by the chamber head. When a combination of cartridge and chamber dimensions are far enough out of spec, the round will hang off of the extractor tightly enough to allow the primer to fire.

I'll bet, as you say, a whole lot of pistol breakage at the extractor may be related got unusual stress related to chamber and case fit. I have seen and heard so much about extractor breakage.

I had never considered that certain handgun c cases might be crushed down without stretching. There would be minimal stretch, and resize, expand, seat, and crimp will all press downward. I should have known that.

It's a great random education at these places.
 
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