Small base sizing for .30 carbine??

C

condor bravo

New member
I just purchased a new Inland .30 M1 carbine, what they call the 1945 model (has bayonet luge). Having a WWII carbine on hand, reloads were already available that were prepared with RCBS and Lee carbine sizing dies using once fired Armscore and Federal cases. Right away there were failures to chamber with 2 or 3 rounds out of 10 with the reloads (lacking about 1/4 inch from complete chambering. And occasionally a factory round of either would not chamber either.

Miking the brass, factory Armscore measured .349 at the base; fired reloaded brass measured .350 at the base; and resized brass measured .349. With the Federals, factory measured .350 at the base; fired measured .353; and resized measured .351. Same results with both sizing dies.

Possibly additional base sizing is needed but there does not seem to be a small base sizer for the carbine. But some sources indicate that smaller base sizing can be obtained with steel dies. Does anyone have any experience with this situation and hopefully a solution?
 
Do not know much about the 'new' Inland carbines, but the re-sized bases seem to be within spec.
First thing I would check would be case length.
Carbine brass does require trimming for the carbine, at least mine does.

Next would be to get a case gauge. It really does save time on the range
and will eliminate ammo prep from the equation in the future.

Third would be several different magazines to eliminate that aspect.
If the gun was still acting up I guess I would probably look to a new recoil spring (Wolff) if
my loads (full power) did not function the gun properly after a good cleaning and lubing.

JT
 
I have both a Rockola and an 1943 Inland so I also can't answer the question about your newly manufactured Inland.

JT-AR-MG42 response above is spot on advice.

Are you using the magazines that came with the new carbine? I've found the magazines coming from Korea are excellent. There are a lot of crappy M1 Carbine magazines on the market. I have learned this the hard way.

I did some case measurement using Lee, Hornady, Herters and a brand new steel RCBS M1 Carbine sizing dies. I was surprised to find the Lee die matched the SAAMI specification and the other did not especially at the base of the case. The Hornady sized the base the least. Only the Hornady sized case failed to chamber in the Inland. (My Inland's barrel was replaced with a new barrel 3 years ago.) The others sizing dies were working the brass more, sizing the smaller than SAMMI. To me the die that worked the case the least was the best choice and still chambered in both rifles.

If the magazine isn't the problem then I would call Inland and see what them recommend.
 
Some years ago my brother and I both had surplus 30 carbines. His was a very nice early manufactured Winchester, mine was a later IBM. My gun would eat just about anything you put in it, his was pickier, especially with our handloads. Small base dies were needed for his gun, apparently the chamber was on the tight side of spec.

Get some Cerrosafe and do a casting, that will tell you if you need small base dies or not.
 
Re: the above replies are all logical. The peculiar thing is that the sized brass does seem to be in specs. When the feed failures occur sometimes a good shove with the palm of the hand against the operating rod handle will chamber the last 1/4 inch of the round. Other times the round must be extracted with a few blows from a mallet.

Magazines have been checked out fairly well. I have 4 10 round mags, 1 20 round that came with the carbine, and 3 30 round. One of the 10 round mags was determined to be bad and has been discarded. The 30 round mags are the smoothest and work the best.

Now I'm in the process of obtaining a steel die and perhaps the reports of steel dies doing a better job may be the answer. Is anyone using steel dies and how do they work?
 
Even though the brass is "in spec" doesn't mean it will fit the chamber. Reamer wear out, and hence, get smaller, making the chamber smaller.

There are a few other things to try. On a round you have to jam in, pull it before firing and check the case for any marks, especially on the neck, add check the bullets for rifling marks. If you're getting a crimp like mark on the mouths likely your brass needs trimmed. Rifling marks on the bullets likely means the bullets need to be seated deeper.

Also, do you mean "carbide" dies is what you're using, or just "30 carbine" carbide is the material that doesn't need lubed "usually" carbine is a type of firearm. I usually wouldn't bring this up, but since both are applicable, I thought I'd ask

Sent from my SM-G900V using Tapatalk
 
nhyrum:
Yes, the two sizing dies are the carbide type rather than steel. No I haven't checked for marks on rounds that had to be extracted--good idea and will do next time. Note that cases are lubed even with the carbide dies.

Loaded rounds are just taper crimped to remove the flare.
 
Most 30 Carbines that I have experience with, all World War II models, have generous chambers on them. No need for small bass dies. Sounds to me like you have an undersized chamber.

Best regards Rod
 
CB

As a test, take some of your reloaded ammo,
try it the chamber,
when you find any ammo that hangs up or sticks,
pull those rounds and color them with a magic marker,
from the extraction groove to the top of the bullet.

Take these rounds and rechamber them again,
you'll find the areas that are causing the hang ups etc,
then correct those areas etc.

HTH,

Tia,
Don
 
All those measurements are fine. SAAMI says .3548" with a -.008" tolerance is the case diameter at the extractor groove. Sounds more like an OAL issue to me.
Don't believe there is such a thing as an SB die for .30 Carbine anyway. Although unreliable sources suggest RCBS only makes SB .30 Carbine dies. Only ever used Redding Carbide myself. Never had any kind of issue.
 
I'm ready to conclude that the chambering problem with the new Inland carbine is simply a tight chamber rather than anything with the reloads, as everyone has concluded. Before going out today I did a thorough chamber cleaning job which resulted in an improvement. Fifty reloaded rounds of Armscor brass chambered without failure as did eight rounds reloaded with Winchester brass. Then things started to go bad again and chambering failures occurred with everything including factory Armscores. Note that most failures lack 1/4 to 3/8 inch from complete chambering. In the meantime the old WWII carbine flawlessly digested everything that I had to feed it. So it's looking like a chamber scrubbing is needed after each firing session. The steel RCBS sizing die is in transit and will see if that helps to reduce case dimensions upon reloading which could still be benificial.
 
The RCBS steel die arrived right after making the above post and it does undersize the base of the cases as reported by various sources. Fired cases checked were Armscor, Federal, Winchester and military LC. Keep in mind that the fired cases all had different base diameters of course which accounts for the difference in the amount each brand was additionally sized. The Armscores at the base of the case undersized an additional .0005 to .001. The LC military the most undersized at around .002 to .0025. The Winchesters and Federals in between around .0015 to .002. All this should help the chambering situation along with a clean chamber.

For anyone interested, the Midway product number for the steel die is 432749 and the cost is around $28. The steel die sizes with no more effort than the carbide.

Note: the use of the term "undersize" means that the case bases were reduced the amount indicated by the use of the steel die over the carbide die. So it might actually be said that the steel die over sizes, but leaves the case bases under size compared to sizing with the carbide die.
 
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Be cautious when a m1 carbine is hesitant chambering a round. It has a floating firing, and a bridge that keep the firing pin from hitting the primer until the action is in full battery. But the bridge is only in effect in the last 1/8" or so. If the cartridge stop before that, a out-of-battery ignition is possible.

Tight chamber in this sort of guns is not a good feature. For a new gun, I'd send it back to the factory to re-ream the chamber.

-TL
 
Good point with the slam fire consideration; I hadn't even thought about the carbine having a floating firing pin. But with a trio of Garands I'm well aware of the likelihood. Hopefully the new steel sizing die will eliminate the problem; will know next time out in a couple days. The situation is (hopefully was) especially bad since factory rounds would sometimes not chamber. Thanks for that tidbit of information.
 
For sure the real concern is that it happens even with factory rounds. The gun is border line out of spec, and it requires specially made ammunitions.

Slam fire is the rifle firing more than one round for each trigger pull. It is not kosher but the rifle is still intact. Out of battery ignition is way worse. If it happens, it will destroy the rifle, plus something else.

BTW, I don't trust Armscor ammo at all. I had very bad experience with it with my IBM.

-TL
 
Yes a slamfire is different than an out of battery firing and the latter catastrophic as you point out. I've had three double firings with the Garands but the incidents were not thought to be slams. I can't complain too much about the Armscores since I received 1000 rounds as a present and they are definitely the best for reloading out of the four brands being used. Also had one box of PPUs but discarded the brass, don't recall the reason, after they were fired.
 
m&p45
Are you referring to new brass like Starline? Unfortunately don't have any at the moment but that would be a good test. That should go on my shopping list.
 
Nope not new brass. Run the brass you are going to reload. See how it chambers with no bullet. You will have to manually feed them. If they are going into battery you will not need a amall base die.

If the brass chambers fine then the offending rounds can be fixxed by backing off the seating plug, and turning the crimp down another eighth to quarter turn to iron out the flare.
 
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