I recently purchased a Crosman F4 nitro piston from Walmart. It took me quite awhile to get the scope sighted in at 15 yards. I had to learn how to use artillery hold and aim extremely carefully. I replaced the center point scope with a Winchester daisy and zeroed it in so I could group 5 in an inch or so. I found that the 10.5 grain lead and 10.6 grain copper worked the best. However, after shooting a few hundred rounds through the gun, I noticed I was missing my spinner target. I found my poi was about 3 inches too high. I re zeroed the scope and all is well. However after researching break barrel air guns, I found that running a scope is not recommended due to the fact that the scope is not on the barrel and the barrel is moved every time it is cocked. There is also a condition called barrel sag that will eventually occur. I have found that there are nitro piston rifles on the market that have fixed barrels with a separate cocking lever. I really want to use a np because of it’s power and relative quietness. I have a daisy 880 that is a tac driver at 15 yards, but will not always dispatch a squirrel if my aim is just a little off. That is the reason I want more power plus loading the pellet is a pain and having to pump it 10 times is just too much effort. I really like the Crosman, but it doesn’t have iron sights and I Don’t trust the scope. Is there a way to mount some after market iron sights and what np rifle that isn’t a break barrel would any of you recommend that won’t break the bank (Thinking $275.00 range). Thanks for any help and info you guys can provide.