I AM NOT RECOMMENDING THIS LOAD TO ANYONE. THIS IS WAY IVER RECOMMENDED PRESSURE.
A few buddy’s and myself have been doing a lot of testing trying to optimize our 6 arcs to run high pressure ammo and I wholeheartedly believe the surefire OBC is a necessity for high pressure ammo.
The pic above is 32.2gr of lever with a 90 TacTx from a 14.5 DDF and the surefire OBC with a CAT VB6 suppressor. Anyone who has run high-pressure ammo knows your brass gets absolutely mangled. The OBC delays the unlocking long enough to allow pressure to drop before extraction. Also, based on the counterweight design in the carrier, it slows the carrier down during unlocking which reduces stress on the lugs.
We also tested the LMT enhanced carrier with an A5H4 buffer and while it helped, it performed quite a bit worse than the OBC.
The OBC also reduces recoil to a similar feel of 556 with 77gr.
I’m right around 600 rounds with the OBC and bolt gun pressure ammo and have had zero failures. I personally am not running the load above but I am running Berger 105s at 2700 out of an 18in PXT suppressed. Time will tell if it extends bolt life but if you want reduced recoil or to reload high pressure ammo, the surefire OBC is a definitely the way to go.