Fixed the problem perfecty
Highly recommend this upgrade
Recommend highly to the ar world.
I bought a 7.62x39 complete pistol upper that already had the enhanced firing pin and upgraded extractor. After firing about 2 mags of steel case ammo, the upper would get warm and start having issues extracting the spent casings. I installed this spring and it still had issues. I then also installed the o-ring and no more issues extracting. I've run a few hundred rounds through it since and everything cycles and performs flawlessly. I also installed them in my 556 rifle and pistol. I definitely recommend if running steel case in your AR platform.
Was having issues with shells ejecting from a new 300 Blackout build and this kit solved all issues with extracting the shells.
Bought to upgrade bcg's from another company.. thanks bcm for having quality parts
Its a heavy spring! working good so far on a Fail Zero BCG in a pistol build.
Simply The BEST!