12-04-2020, 08:51 PM
Remember when replacing the carrier key fasteners to toss the old fasteners. They arent meant to be re-used.
A lot of carriers come with Taiwanese-made YFS fasteners. In high volume where the temps get elevated in the carrier, these have been known to occasionally break and lose the gas seal between the carrier and key.
Ive shot untold numbers of AR-15s in high volume that have YFS fasteners and didnt fail, but there are some that have failed and were documented as the source of the problem.
Shows up as short-stroke malfunctions that otherwise cant be diagnosed until you dig more deeply into the carrier/carrier key, or set the torque wrench and attempt to back-out the fasteners.
Also, the original torque spec for RLGS M16s was lower for the fasteners. A change was made for the M4 to increase the fastener torque value to 55 inch pounds, I suspect from the increased heat from higher port pressure coming from CLGS.
Something to think about. On 5.56 guns with the RLGS, you dont see a lot of issues with bolts, fasteners coming loose, or anything really. As the gas system gets shorter, thats when you really need to pay attention to setting the gun up more ideally.
A lot of carriers come with Taiwanese-made YFS fasteners. In high volume where the temps get elevated in the carrier, these have been known to occasionally break and lose the gas seal between the carrier and key.
Ive shot untold numbers of AR-15s in high volume that have YFS fasteners and didnt fail, but there are some that have failed and were documented as the source of the problem.
Shows up as short-stroke malfunctions that otherwise cant be diagnosed until you dig more deeply into the carrier/carrier key, or set the torque wrench and attempt to back-out the fasteners.
Also, the original torque spec for RLGS M16s was lower for the fasteners. A change was made for the M4 to increase the fastener torque value to 55 inch pounds, I suspect from the increased heat from higher port pressure coming from CLGS.
Something to think about. On 5.56 guns with the RLGS, you dont see a lot of issues with bolts, fasteners coming loose, or anything really. As the gas system gets shorter, thats when you really need to pay attention to setting the gun up more ideally.
NRA Basic, Pistol, Rifle, Shotgun, RSO
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com
CCW, CQM, DM, Long Range Rifle Instructor
6.5 Grendel Reloading Handbooks & chamber brushes can be found here:
www.AR15buildbox.com