make sure you..

get a airgun rated scope for the b21 because the recoil kick is harder on regular scopes. I picked up a Powerline 3-9X40 for 28 dollars at walmart and it works great on my b21. I also had to use a BAM single piece scope mount to keep the scope in place. Those b21's sure hit hard.

Would like to see some pics of your gun's if you get a chance..

http://www.kcugonline.com/kac/

Kermit Airgun Club