I am in the process of putting together a hopefully very accurate target rifle.  I started with a RRA 24" Varmit rifle with the bull barrell, free floating barrel, Egro Target Grips, weighted stock, etc.  I put an old 9x scope on it and I was able to shoot sub .75 groups at 100 yards with match grade ammo.

Well, I just purchased a new Bushnell Elite 3200 7x-21x variable scope but needed to move it forward a little farther than normal to get the correct eye releif, so I also purchased a B-Square cantilever mount.  After putting it all together tonight, I think the scope is sitting too high off the barrell.  There is about an inch between the bottom of the lense and the handguard, and probably close to 2.5" of clearance between the center of the scope and the actual barrell.  Any thoughts on whether this really is too much clearence for a really accurate gun?  Assuming we leave the setup as is, can anyone help me with the correct balistics to zero the scope at for the best accuracy at varing range.  Ie, should I be looking to zero at 100 yards, 150 yards, etc knowing that I will be shooting mostly in the 100-200 yard range.

I appreciate any help!  Shawn

The Larue Tactical SPR-1.5 mount will put your scope at the right height and proper eye relief.  

They're spendy, but you'll never have to buy another mount and you won't be spending a big chunk of change trying to match parts from various manufacturers

Larue mount with big honkin' scope on my AR



Same rifle with different scope



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ZM

guessing at around 3000 fps and 69 gr bullets zero @ 150 for about 1/2" high @ 100 and 2"low @ 200, more specifics on your load and i can do better.

Just be careful about canting.