Thread drift alert: I just checked out that Predator Tactical rifle and the little blurb on the site says it recoils like a 20 gauge.
Uhhh, yeah... a 20 gauge SLUG I'm guessing. No way that rifle doesn't punch your shoulder.
I put 5 rounds through a T/C Encore with a .500 Mag barrel on it and it was... memorable. Not a walk in the park. This one may be a little heavier, but it's not going to feel like a clay target load or a bunch of bird shot.
Attention Brass rats and other reloaders: I really need .327 Federal Magnum brass, no lot size too small. Tell me what caliber you need and I'll see what I have to swap. PM me and we'll discuss.