Needing some help

I picked up acouple of Benjamin springers a 177 for my 8 yr old grandson and a 22 varmit for me.First thing I did was throw the scopes away. I put a 3x9x50 centerpoint on the 177.does fine.I put one on the 22 to but I like shooting dimes at 200 yards with my centerfires.So I put on a millit tactical.Now the problems starts.scope is mounted with a pepr one piece mount,I was 5 inches low when I ran out of elevation adj.mmm.So I put on a leupold varmint mounted with z rings I got to half inch low before I ran out of elevation adj.Starting to see red now.After reading a bunch of reviews I orderd a hawk airmax.Like the leupold half inch low and out of elevation.I am not that up on the ins and outs on air rifles.Im just shooting indoors at 12 yards,does the pellit slap down then comes back up like centerfire and I'm to close,is that just the way this gun is going to shoot.Any ideas on whats going on
 
I had the same problems when using a new Center Point, ran out of elevation and windage.....it is probably out of adjustment from the factory.....So...in a well lit area, take your scope and hold it against the mirror, I used my bathroom mirror, and you should only see one cross hair, if you see two, adjust your windage and elevation to get just one set of crosshairs. Then your scope is centered and you can adjust it on target. This is the same for all scopes. Hope this helps.