and preferably also a carrier key staking tool and complete BCG. I posted this story in one of the 5.56 reloading threads but it bears repeating here.
I have a 5.56 gas rifle and it has a 14.5 inch super duty mid-length upper which shot fine for several thousand rounds with h2 buffer + super 42 spring and never had a problem with any type of 5.56 factory loaded ammo from 55 grain plinking to Black Hills 77gr OTM's nor any issues with my hand loads which were mostly 77gr SMK's with TAC. Then the last two sessions I was at the range I was getting stove piping and short cycling and no lock backs with familiar factory ammo and hand loads. I checked the gas rings on the bolt and they tested fine. When I switched to carbine buffer weight and weaker spring I was able to fix the short stroking and it was able to lock back....but something still didn’t sit right with me, it was odd randomly having low gas signs with the same buffer/spring I always used (I thought it was due to less pressure from cleaning carbon rings out more thoroughly before those last two sessions) but luckily @.505gibbs reminded me to check the gas key screws and that was the root cause of the problem.
Somehow on this geissele BCG with only a few thousand round on it the gas key screw closest to the gas port sheared off.
To their credit they responded to my warranty claim in less than 24hrs and are shipping me a new carrier/key and included shipping label for me to send the old one back.
In the future I will have spare gas key, screws, and sealant on hand. Torque them down with some oil to 50 in-lbs with some sealant and a smoothed face and it will work in a pinch without staking. I will also test up to 30 in-lbs the screws any time I take the carrier out just to see if any are egregiously loose.
Hopefully this PSA helps folks avoid the same headache I was trying to trouble shoot.
For some good tips on installing a new gas key, etc. see this SOTAR video:
I have a 5.56 gas rifle and it has a 14.5 inch super duty mid-length upper which shot fine for several thousand rounds with h2 buffer + super 42 spring and never had a problem with any type of 5.56 factory loaded ammo from 55 grain plinking to Black Hills 77gr OTM's nor any issues with my hand loads which were mostly 77gr SMK's with TAC. Then the last two sessions I was at the range I was getting stove piping and short cycling and no lock backs with familiar factory ammo and hand loads. I checked the gas rings on the bolt and they tested fine. When I switched to carbine buffer weight and weaker spring I was able to fix the short stroking and it was able to lock back....but something still didn’t sit right with me, it was odd randomly having low gas signs with the same buffer/spring I always used (I thought it was due to less pressure from cleaning carbon rings out more thoroughly before those last two sessions) but luckily @.505gibbs reminded me to check the gas key screws and that was the root cause of the problem.
Somehow on this geissele BCG with only a few thousand round on it the gas key screw closest to the gas port sheared off.
To their credit they responded to my warranty claim in less than 24hrs and are shipping me a new carrier/key and included shipping label for me to send the old one back.
In the future I will have spare gas key, screws, and sealant on hand. Torque them down with some oil to 50 in-lbs with some sealant and a smoothed face and it will work in a pinch without staking. I will also test up to 30 in-lbs the screws any time I take the carrier out just to see if any are egregiously loose.
Hopefully this PSA helps folks avoid the same headache I was trying to trouble shoot.
For some good tips on installing a new gas key, etc. see this SOTAR video:
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