Hello. I'm experiencing short stroking with handloads through my M1icon. I had been trying between 45.5 and 48.0 grains of IMR4064 and Varget with 168 grain A-Maxes in LC Match brass set off by CCI #34 primers seated to 3.240" COAL.

The supplier of the M1 sent me a different Op rod and gas cylinder, which made no difference. I then bought some Greek HXP mil surp ammo, which ran fine. Since it runs with mil surp, he says the problem is my handloads.......not the rifle.

As the Greek is loaded with 52 grains of ball powder (which I presume to be faster than IMR4064), I bought a pound of H4895 and used between 45.5 and 47 grains with the above mentioned details with the same short stroking.

For today's test session, I switched to 150 grain Sierra GameKings and loaded 8 each with 47.0, 47.5 and 48.0 grains of H4895 (with the above details). I experienced multiple short strokes with the 47.0 and 47.5 grain loads, but made it through the clip with 48.0 grains. Thinking it didn't like 168 grain bullets (no reason I know if it shouldn't), I also tried 49.5 grains of the Greek powder with 168s (and the above details) with success.

I'll load up some more of the 48 grains of H4895 driving 150s for the next range session, but won't be surprised if I don't make it through two clips.

Am I wrong in thinking that all of the above loads should work 100% in my rifle? Should I try a slightly faster powder than H4895? Should I go back to the seller again, as it's under warranty?

I appreciate any advice you're able to provide.
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