@occidio so it does make sense, a GBB auto volumes, which yes I agree if you fastidiously volume matched an AEG cylinder you could achieve ‘nearly’ the same affect AKA joule creep.
I say ‘nearly’ because there is something about the way a GBB accelerates a BB, until the floating valve closes.
AEGs simply cannot accelerate the BB in the same manor, I think this is down to the short stroke of an AEGs piston, circa 40mm.
As such to get DMR FPS the spring is very strong, so the BB is ‘popped’ more than accelerated.
A BASR has a much longer stroke allowing for better acceleration.