What is the average size gas port size for a 20" LW50 polygonal barrel with rifle-length gas system? I installed a restrictor inside the end of my gas tube and am drilling it out to get the rifle functioning without overgassing.
.073" was severely undergassed resulting in "outty" primers that looked like nipples where the firing pin hit
.076 almost worked, short stroked primers looked normal
.078 or .080? (I broke these drill bits awhile back)
My next drill bit is .083.......
.090 is WAYYY too large, enough to flatten the necks of the cases against the deflector
.073" was severely undergassed resulting in "outty" primers that looked like nipples where the firing pin hit
.076 almost worked, short stroked primers looked normal
.078 or .080? (I broke these drill bits awhile back)
My next drill bit is .083.......
.090 is WAYYY too large, enough to flatten the necks of the cases against the deflector
