Hello, new to the forum, though I have been spectating from the sidelines for quite a while.
There is so much good information here, I was able to scratch build a Grendel and it is working just fine. The barrel is 20" with rifle length gas, using an Odin adjustable gas block.
When I shot the first 50 rds. the set-screw was backed out to what should be completely open. Function was trouble free, but my brass was getting beat up, and the rifle seemed to be getting thrashed a bit as well -kind of noisy in the A2 stock and a lot more general noise and mechanical crashing than our 5.56 AR.
Next range session I started with the adjustment lightly bottomed, then progressively opened more after each shot until ejection was consistent and the bolt locked open (properly on the bolt catch) after mag. was empty. Then added about 1/4 turn more to allow for carbon build-up and differences in ammo. Brass is not getting case mouths mashed, and the rifle is much calmer feeling in recoil.
This testing/break-in was all done with factory loads: Hornady Black 123gr. ELDM, and Prvi. 120gr. HPBT (Sierra bullet?).
Today is the day to try some handloads and start fine tuning the rifle -hopefully- for upcoming winter predator hunting, and possibly a Caribou.
The barrel got a thorough scrubbing and some strokes with JB bore paste; cleaned and lightly lubed the recoil spring; and buffed some spots on the bolt carrier and hammer that were not mating in a smooth way.
My question is, is there a "standard" procedure or guideline for setting the restriction on the gas block?
This rifle will see at least two or three different loads, and I don't want to be so precise with the setting to have a short-stroking issue if ammo is changed.
Thanks in advance to all who reply!
There is so much good information here, I was able to scratch build a Grendel and it is working just fine. The barrel is 20" with rifle length gas, using an Odin adjustable gas block.
When I shot the first 50 rds. the set-screw was backed out to what should be completely open. Function was trouble free, but my brass was getting beat up, and the rifle seemed to be getting thrashed a bit as well -kind of noisy in the A2 stock and a lot more general noise and mechanical crashing than our 5.56 AR.
Next range session I started with the adjustment lightly bottomed, then progressively opened more after each shot until ejection was consistent and the bolt locked open (properly on the bolt catch) after mag. was empty. Then added about 1/4 turn more to allow for carbon build-up and differences in ammo. Brass is not getting case mouths mashed, and the rifle is much calmer feeling in recoil.
This testing/break-in was all done with factory loads: Hornady Black 123gr. ELDM, and Prvi. 120gr. HPBT (Sierra bullet?).
Today is the day to try some handloads and start fine tuning the rifle -hopefully- for upcoming winter predator hunting, and possibly a Caribou.
The barrel got a thorough scrubbing and some strokes with JB bore paste; cleaned and lightly lubed the recoil spring; and buffed some spots on the bolt carrier and hammer that were not mating in a smooth way.
My question is, is there a "standard" procedure or guideline for setting the restriction on the gas block?
This rifle will see at least two or three different loads, and I don't want to be so precise with the setting to have a short-stroking issue if ammo is changed.
Thanks in advance to all who reply!
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