Yeah...that again...brand new upper built as follows.
Gibbz side charger
WELL USED - JP QPQ full mass carrier
NEW - JP Bolt with gapless rings
20" Barrel - SAAMI Spec
MLGS - yeah i know its weird
fixed gas block
.067 gas port
JP Captured spring recoil system
port alignment is perfect. Port isn't plugged. No maching burr or trash in it.
test ammo is Hornady factory amax load.
test weather is 90*, baro at 29.99
symptom - short stroking regularly, but not every round. Perhaps 1 out of 3 rounds will result in a F2F. All brass dribbles out gently beside the rifle and will stay on the bench in my shooting stall. I'm against a wall but they lack the velocity to go bouncing off the table.
Bolt will not lock back on an empty mag. Mags are ASC
Seems pretty obviously undergassed to me and port seems way too small. I'm thinking i need a .078"
any alternative suggestions?
thanks
Gibbz side charger
WELL USED - JP QPQ full mass carrier
NEW - JP Bolt with gapless rings
20" Barrel - SAAMI Spec
MLGS - yeah i know its weird
fixed gas block
.067 gas port
JP Captured spring recoil system
port alignment is perfect. Port isn't plugged. No maching burr or trash in it.
test ammo is Hornady factory amax load.
test weather is 90*, baro at 29.99
symptom - short stroking regularly, but not every round. Perhaps 1 out of 3 rounds will result in a F2F. All brass dribbles out gently beside the rifle and will stay on the bench in my shooting stall. I'm against a wall but they lack the velocity to go bouncing off the table.
Bolt will not lock back on an empty mag. Mags are ASC
Seems pretty obviously undergassed to me and port seems way too small. I'm thinking i need a .078"
any alternative suggestions?
thanks
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