Go for it!!!! But remember this, if you want power and higher velocity,..stick with the factory spring. Oh yeah,...you'll figure it out soon enough!!!! If you want a smoother ride with less cocking effort and easier shooting, I'd opt for the tamer Macarri spring. Mike will fit it to your preference. As for the seal,... believe it or not,..the Factory seal works better than the after-market seals,....with both spring combinations!!! My .22 B-28A may not be the "super-duper" power house with the mac spring,..but it's got enough juice to get the job done out to 40/50 yards ,..no problem!!! But even better,..she's a smooth operator!!! With the OEM.177, it's riping my brand new spinner spoons apart at 25 and 30 yards,...and this factory mare has some kick as well. Control is everything, but you'll have to loosen the reigns if you go OEM!!!!! Some horses just gotta run free!!! Giggling now. Good Luck, tjk