M1 Rifle Short Stroking

[Parashooter]

After eliminating the contact, it still won't cycle 45 to 46.5 grains of H4198 with 1568s.
Grizz

Interesting powder designation - and a very heavy bullet. This is a good example of why one can never trust data found on discussion boards.

Sometimes I wonder if you guys ever bother proofreading.

[Grizzman]

Allright, I had a bit of a problem with numbers, and I 'm done trying to post from my BlackBerry (my other posts are obviously not hack jobs and more complete than most people would consider typical).

Here's the correct information:

After eliminating the contact, it will still only chamber the last couple of rounds within a clip with loads using 45.0 to 46.5 grains of H4895 with Hornady 168 A-MAXES or Sierra 150 GameKings in mil brass with CCI #34s.

Guess I'll just stick with H414.

Is there a way to edit past posts? I sure don't see it.

Grizz

[Darkwolfe]

How did the 4895 and Varget loads work out?

[Grizzman]

There was no improvement at all with Varget and H4895. It still functions fine with Greek HXP. I colored the band black with a sharpie to easily see any contact, and there was none.

I still think that the issue is with the op rod and/or gas cylinder. The piston on the op rod that I was sent as a replacement measured the same as the original one.

Grizz

[TDH]

I use 47 grains of either H or IMR 4895 or varget and mine works just fine.

I also use 40.5 grains of the same powders in my .308 Garands with good results.

They are about in the middle of the suggested load data in the Lyman book.

[Darkwolfe]

At this point my thought is get another gas cylinder/op-rod combo and test that. Not a cheap fix, but it's kinda getting to that point.

TDH- Interestingly enough, I actually use 40gr flat of 4895 in my 30.06 M1 with my cast bullets with no issue at all. Of course they are a bit larger than jacketed bullets and are gas checked as well.

[Grizzman]

I've got a local friend with an M1, so I'll see if he wants to meet me at a local range. If I load up some ammo withe 46.5 grains of Varget and test it in his M1. If it works, then I can put his op rod in my M1 and try them out. If that still doesn't work, then I can put his gas cylinder in my M1.

This won't solve the problem, but it'll at least possibly allow me to identify the cause. If the op rod ends up being the cause, I see that Columbus Machine Works can replace the piston, and there are likely other options for that service also.

Grizz

[Darkwolfe]

There's also ammogarand.com. I've gotten a part or two there with good results. Let's hope the solution becomes clear in short order. I hate the idea of having a "down" rifle in my cabinet. I don't imagine you like it much either.