Thanks for this post, your explanation about the “piston” size in relation to the bullet weight makes complete sense to me as to what you’re thinking. Should be interesting to see the results. A close friend and I messed around with some of the Remington Accelerators in his dad’s M742 back in college and couldn’t get them to groups work a sheeit. The faster twist from a 300blk barrel may solve that issue. At the very least you should be mirroring a 5.7x28, which could be fun for varmints and targets.