Bolt not locking on last round

[titsonritz]

Actually, I don't think the guy posting about trimming the spring was the OP. Even with that solution, it doesn't necessarily mean the issue was the lower instead of the upper. The guy with the similar issue piggybacking the thread could still have a rifle that is under-gassed. I'm assuming the spring he trimmed was the buffer spring, which reduces the amount of load required to lock the bcg back on the last round. Like with most gas issues, the problem is in the upper, and the solution is achieved by adjusting the lower.

I got that it was the bolt catch spring he was referring to.

[Kdubya]

I got that it was the bolt catch spring he was referring to.

That's equally plausible. I've had buffers on the brain recently. Hopefully Kilbo can confirm what was done, as it might help the OP.

[titsonritz]

That's equally plausible. I've had buffers on the brain recently. Hopefully Kilbo can confirm what was done, as it might help the OP.

I gathered it from this statement: "the well for the spring in the receiver was too shallow."

[Mysteryman]

Actually, I don't think the guy posting about trimming the spring was the OP. Even with that solution, it doesn't necessarily mean the issue was the lower instead of the upper. The guy with the similar issue piggybacking the thread could still have a rifle that is under-gassed. I'm assuming the spring he trimmed was the buffer spring, which reduces the amount of load required to lock the bcg back on the last round. Like with most gas issues, the problem is in the upper, and the solution is achieved by adjusting the lower.

I missed the piggyback guy doing the answering.. Either way clipping coils off your recoil spring to make your rifle "run" is absolutely wrong. Your rifle should work with factory parts in unaltered condition. Same goes for the bolt catch spring or any spring.

MM

[Kdubya]

I missed the piggyback guy doing the answering.. Either way clipping coils off your recoil spring to make your rifle "run" is absolutely wrong. Your rifle should work with factory parts in unaltered condition. Same goes for the bolt catch spring or any spring.

MM

I agree clipping coils, on any spring, is not likely the correct solution. It might work, but that doesn't make it the best fix. Although, I do know of at least one mfg of recoil springs who says theirs can be clipped to adjust the load. Still, after hearing how others read the piggybacker's comment differently, I'm not certain which spring he clipped.