M1A Ammo requirements

rolfyrolf

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I just read the manual for the M1A, and it says that you need to use military ammo for the gun to avoid slam fires, is this purely a butt covering statement or do you need a harder primer to be safewith this gun. Most people I know use commercial .308 for the M1A.
 
Whatever ammo you use, restrict yourself to the normal operation of only loading by having the bolt strip a round from the magazine. Do not feed a loose round into the chamber and drop a bolt on it. Many say to do otherwise increases the odds of having a slamfire, as the bolt and firing pin will meet the cartridge and primer at an increased velocity.
 
i didn't have any slam fires with my m14, but i have looked at a few rounds that i have pulled out of the chamber without firing them from time to time, and they all did have small indentations on them,from the contact of the bolt now, would that be enough to cause a slam fire, well after firing 400 rounds....no but i do support avoiding to put a round by hand and then closing the bolt...i will not try the experience.

but when one looks as a spent m-14 round, the dent left in the primer of a military rifle is very deep compared to one made by a hunting rifle... so i guess in theory its possible.

i dont think i would lose sleep over this, dozens of m1, m-14 and Garand owners go to the same range i go to, not once have i heard of a round going off by itself, hopefully, it will remain that way.

p.s. any truth in the statement that going above 150 grains in a m14 is a bad idea?
 
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The indent in the primer is normal and is unavoidable. It is good measure to make sure you are using ammo that is compatible with the rifle, but most factory 150g 308 stuff will be OK.

When I reload, I use CCI 200's only cause I know they have never given me problems and I'm not going to risk trying others. I can't get mil-spec primers locally.

I've cycled all sorts of silly things thru my M1A with no problems.


p.s. any truth in the statement that going above 150 grains in a m14 is a bad idea?

YES, on paper.

Factory 180g rounds often use much slower burning powders so they can achieve similar velocity and point of zero as their 150g counterparts.
This slower powder can overdrive your gas system and damage the rifle, so it is not recommended.

IF you're shooting factory, use 168g max. 168g rounds are often Match rounds made to a standard that has the M1A in mind.

180g factory is made expecting that it's likely to be used as a hunting round out of a generic rifle, most likely Bolt Action. If you have a recoil buffer you could probably get away with it, but I'm not interested in trying.

150g does not need any special slow burning powder to achieve it's spec performance.

On a side note, I shoot 180g out of my M1A almost exclusively, but they are reloads using a powder within the spec burn rate for the rifle.
 
In the 8 years that I've had my M1A I've experienced one slam-fire, and oddly enough it was with Portuguese Surplus Military ammo.

If your going to reload for your M1A you're best to use harder primers, I believe CCI and Winchester are slightly harder than Federal. I think people have had good results with S&B primers, though I haven't tried them myself.
 
My 168 grain handloads with 41 to 42 grains of IMR 4895 eject so gently, the brass lands beside the rifle. I'm not sure if that is conclusive that this load is delivering less pressure to the gas system, as I'm not sure if bolt opening speed determines ejection vigor, as the ejector is a spring and not a function of the bolt moving rearward, aside from the front of the cartridge clearing the chamber.
 
you'll find you can play that 180 grain game for only so long before your op rod breaks or something else gives way- there's a reason that the us army marksmanship unit went back to the 175-173 grain loading at 2550 fps- ACCELERATED WEAR- and adding a buffer CAUSES all sorts of problems with the return stroke-
we've re-hashed this so often and in so many ways it isn't even funny anymore-
LOOK UP ZEDIKERS M14 MATCH LOADS- TAKE THE TIME TO READ IT or i can nutshell it for you- yes, you can use loads of greater than 150 grains, PROVIDED you stick to 175 or under-
YOU CAN USE 150s without any trouble, but they may not group the best
and i've proven this extensively- the best loads are 165-168 grain( 165 hunting, 168 for match, and limit to about 600 m
 
That's pretty much what I was trying to say, unless, you were addressing me.

I have read Zedikers Manual, and yes, if anyone reading this is thinking of getting into reloading for the M1A, it's def recommended reading. That and DON'T YOU DARE even THINK about reloading for that thing without the headspace gauge he mentions. Also, get a primer pocket uniformer and a Ram Primer while you're at it.

180 is the biggest I'll go and the load is compensated. The military going back to 174's is likely due to them not getting the performance specs they wanted out of the round without the accelerate wear. I don't push the 180's that hot.

I use a slighter faster burning powder then normal, 3031, and at 38 grains I'm only getting 2400fps average out of my hand loads. I admit, I probably could not touch 2550 without overworking the gun.

If I'm wrong, then time will tell, but my rifle is not complaining, heck, that's it's favorite dish, it just won't shoot anything else as I've loaded as consistently. Half cause I can't afford to feed that pig the 168g standard at the volume in which I shoot it.
 
you'll find you can play that 180 grain game for only so long before your op rod breaks or something else gives way- there's a reason that the us army marksmanship unit went back to the 175-173 grain loading at 2550 fps- ACCELERATED WEAR- and adding a buffer CAUSES all sorts of problems with the return stroke-
we've re-hashed this so often and in so many ways it isn't even funny anymore-
LOOK UP ZEDIKERS M14 MATCH LOADS- TAKE THE TIME TO READ IT or i can nutshell it for you- yes, you can use loads of greater than 150 grains, PROVIDED you stick to 175 or under-
YOU CAN USE 150s without any trouble, but they may not group the best
and i've proven this extensively- the best loads are 165-168 grain( 165 hunting, 168 for match, and limit to about 600 m

How many rounds of 180 would it take to see premature wear or damage?
 
most of us value our rifles too much- it's probably in different's book somewhere- i DO remember seeing the charts on line somewhere;and the GARAND has volumes on using the wrong pressure load , breaking the welds on the oprod, and having it re-welded- now , it follows that any problems with the basic design of the garand is going to follow with the son, the m14- aside from the half inch shorter, and the twist of the barrel, it's the same rifle; as for destructive testing, what the us army marksmanship unit says is good enough for me- these guys used to travel with a full van of parts and re-built their rifles (with an armourer who know what he was doing) whenever the rifle would START to show signs of wear- they'd go out , shoot a match, and then turn the rifle back in for "assessment"- the armourer would then go over every surface with a micrometer to see if it was still in spec- if it wasn't, he'd either replace the part, or re-surface ( yes, he was that good) to bring it back to spec- most of us have NO IDEA of the support the amu has- and it's a BLUE panel van
from battle rifles ,com" the use of 180 grain bullets is not recommended due to BENDING OF THE OP ROD and CRACKING OF THE RECEIVER- the cracking of the receiver is a new one even to me, but it is there in the search engine- now that seems someone on that board has done some testing as well as the amu, and a cracked receiver is something i DON'T want to chance
 
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