FX Crown .30 700mm 3 10 shot groups at 100 yards

Good shooting Dakota. I’d reevaluate shooting with the foam. That group appeared to have a much better vertical dispersion than the other two groups. Looking at your video while shooting, the barrel jumps and flexes much more without the foam. Just my 2 cents. 
Mike

Putting the foam out at the end of the air cylinder, might make more of a difference.

I agree with centercut. There is an obvious difference in barrel movement and flex with the foam inserted. Much less barrel movement, and way better vertical tightness.