I ordered this Crosman 2250XT from Mountain Air Custom Airguns. One thing he does is add 24" barrel and modifies the valve for more power. He also changes out all the orings to rings that are more durable and will hold up to the hard CO2.
First thing I did to it was put an 88gr to paintball adapter from Bryan and Associates on. I also added a lead dust collector from TKO22. It does a wonderful job of collecting the harmful lead particles.
While shooting 14.3gr Crosman Premiers over my F1 Chrony, I was getting average 667fps on the 88gr tank. Switching to the 9oz tank I was getting 677fps.
I will have to replace the scope as it is TERRIBLE. It is blurry and doesn't seem to be holding zero.
God Bless Yall