Garandicon Poobah (obviously we both watched the Flintstones as kids),

I have shot hundreds of rounds at the range with my 8/41 garand. 90% of the shells eject between 1 and 4 with most at the 2 to 3 position. The rest go to 12 and a few pop me on the head.

How come this variation using the same spring and ejector? I handload but my theory may be applicable to factory loads, too. I think variations in chamber pressure may be the culprit. So many things affect chamber pressure, and, therefore, gas pressure variations at the gas port acting on the op rod piston.

What causes this? type of propellant? diameter of gas port (obstructed by residue), oversize gas port? worn gas cylinder? carbon build-up on surface of piston? gas cylinder position stationary over gas port? Rounds heated in chamber causing chamber pressure increases? Powder in rounds consistently massed at base of shell before firing (hold rifle up to mass powder towards primer before firing), conformity of ammo (commercial vs. military brass)? Cleanliness of chamber? Lubrication of op rod slide on side of receiver? Cleanliness and proper lubrication of spring in op rod? Correct tightness of gas cylinder lock nut? Overall cleanliness and lubrication of all interfacing moving parts? Correct powder (slow-burning vs. fast-burning)? Bullet weight? Consistent bullet/powder/primer manufacture? Action tightly secured in stock? Rifle held consistently taught against your shoulder when firing?

Otherwise, what do I know?

Thomas
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