Having an issue with my new BCM upper - help appreciated
Brand new BMC mid-length upper, 14.5", with Battlecomp 1.5 brake.
Lower has a CS blue-end spring and Spikes T2 tungsten buffer weight.
Started off shooting Wolf 62 grn poly ammo - everything worked great. Switched over to Federal American Eagle 55 grain and everything worked great. Went back to Wolf and suddenly it wouldn't strip off the next round out of the mag. Fired fine, ejected fine, but 50% of the time would not strip the next round off the mag. On the last round it wouldn't push the bolt back far enough to lock the bolt open on the empty mag. But when I went back to the Federal ammo everything worked just right.
Am I correct in assuming that perhaps the Wolf ammo is not as powerful as the Federal and is therefore not giving the bolt enough "oomph" to push it back far enough over the rear of the next round in the magazine to allow for chambering?
Could it be the muzzle brake causing this?
Would I be advised to perhaps try a lighter, shorter buffer spring, or a carbine weight buffer instead of the T2 buffer?