M1 Rifle short stroking

[Grizzman]

Yep, you were right about that, and I had a feeling he'd stumble across the thread eventually and give some helpful info....which he did in spades.

[Dave Waits]

Okay , maximum runout on the piston is .00035 so, it's small, send it to Columbus Machine, while you're at it it would be good to have them check and set the bends. Jim Swartz, when he quit doing this, sold them his equipment which included a $1,500.00 bend-gauge for the M1 Op-Rod.
Your Gas-Cylinder sounds servicable.

If your gas-screw has a single screwdriver slot it's solid, otherwise it's a poppet-valve type(Slot looks like a big lipshead). If it's cross-slotted, turn it upside down, put a 1/8th punch into the slot-center and push down onto a hard surface. The face will rise up. There could be grit or carbon stuck in it holding it partially open. Scrub the inside good with a toothbrush and Hoppes'. Then let it soak in Hoppes' for about 1/2 hour and scrap off the face with a penny until the black(Carbon buildup) is gone. Now, you can check the face for a crack. If you find a crack in it let me know, I have some extra servicable screws.I'll send you one.

Barrel-port- Chuck up the bit(#47) in a variable-speed batterydrill or better yet a Dremel or foredom tool and slowly run it into the port, making sure you run it straight in. It sounds like there's a carbon buildup around the hole.
Dave

[Grizzman]

I cleaned off the face, and it isn't cracked. It's soaking in Hoppes now. It is the poppet style. I just never pressed hard enough to get it to move.

Thanks.

[Dave Waits]

Great! Honestly, I don't like the poppet-valve types. I use solid screws(Single-slots). You can get a repro that works just fine for $25.00. They're just another variable. The idea is consistant operation round to round, that's what brings accuracy to a Garand.

[Grizzman]

I received the op rod back recently. The piston was supposedly in spec at .5257", so he didn't replace it. I ran about 20 rounds through it today, and it fed the 2nd and 3rd round properly about 1/3 the time.

Any other ideas??

I loaded up 48 more rounds with 47.5 to 49 grains of Alliant Reloder 15, which functioned well the last time I tested it. If it works again, I'll likely try out some IMR 4320 or Accurate 2520. I'll settle on the fastest powder that reliably works.

[Dave Waits]

This thread is history, Gas-Cylinder was bad.