Last weekend, I loaded up my two suppressed shorty ARs in my Jeep and drove out to the desert to test them with different buffer weights. I wanted to see just how much changing a buffer actually affected function and felt recoil.
The first shorty is a pistol I nicknamed the "Wolf Pup". I built it shortly after Sig introduced it's arm brace. It's evolved some since it's first inception, but as it sits now, it has a 11.5" barrel, suppressor, standard full auto BCG and an SLR adjustable gas block. The lower uses a pistol receiver extension and at the start of this test, an H buffer & carbine action spring.
The SLR upper was tuned using the lock back check. It was tuned until the round would eject, but not lock back. Opening the gas port one more click resulted in full ejection and lock back. To my surprise, no change to the gas port setting was needed with the different buffer weights. What did change, was felt recoil. While recoil with all three buffers was never unpleasant, recoil with the carbine buffer felt quicker and sharper than with the heavier buffers. Of the three buffers, recoil felt softest and flattest with the H2 buffer
Next, the SLR upper was tried on a lower with the A5H2 buffer and Sprinco green action spring. Again a lock back check was performed. Again, no change was made to the gas port setting. Recoil felt even softer and flatter than with the H2 buffer. Oddly, the carrier speed felt slower, almost sluggish when fired at a deliberate pace. However, that sluggish feeling went away during rapid fire.
I was surprised that no change was needed to the gas port setting when switching even from the lightest buffer to the heaviest. What was really interesting is that the AR shot the softest and flattest with the A5 RE assembly. The conclusion I draw from this test is that taming an over-gassed AR will take more than heavier buffers and stiffer springs. It also takes getting the gas flow.
The first shorty is a pistol I nicknamed the "Wolf Pup". I built it shortly after Sig introduced it's arm brace. It's evolved some since it's first inception, but as it sits now, it has a 11.5" barrel, suppressor, standard full auto BCG and an SLR adjustable gas block. The lower uses a pistol receiver extension and at the start of this test, an H buffer & carbine action spring.
The SLR upper was tuned using the lock back check. It was tuned until the round would eject, but not lock back. Opening the gas port one more click resulted in full ejection and lock back. To my surprise, no change to the gas port setting was needed with the different buffer weights. What did change, was felt recoil. While recoil with all three buffers was never unpleasant, recoil with the carbine buffer felt quicker and sharper than with the heavier buffers. Of the three buffers, recoil felt softest and flattest with the H2 buffer
Next, the SLR upper was tried on a lower with the A5H2 buffer and Sprinco green action spring. Again a lock back check was performed. Again, no change was made to the gas port setting. Recoil felt even softer and flatter than with the H2 buffer. Oddly, the carrier speed felt slower, almost sluggish when fired at a deliberate pace. However, that sluggish feeling went away during rapid fire.
I was surprised that no change was needed to the gas port setting when switching even from the lightest buffer to the heaviest. What was really interesting is that the AR shot the softest and flattest with the A5 RE assembly. The conclusion I draw from this test is that taming an over-gassed AR will take more than heavier buffers and stiffer springs. It also takes getting the gas flow.