20 MOA question

[xtratoy]

I am putting together a 22-250 and have an additional 260 Remington barrel I will be swapping back and forth. If I put a 20 MOA base on it will I have any close range scope adjustment or will the average Variable powered Leupold or Burris scope not have enough adjustment if I wanted to dial in a 200 yard or closer zero? I tend to shoot longer distances but usually don't use the 22-250 much over 500 yards. The 260 would be shot as far as I can find a target. I guess the bottom line is what is the minimum distance a 20 MOA base is good for.

[jhelmuth]

Any distance where there is 20 MOA of "down" adjustment. Simple answer - but that is the deciding factor, and that depends on the scopes range of adjustment and the final scope mounting to the rifle (IE the setup in total).

Assume (for this example) a theoretical setup where the scope has 50 MOA of vertical (elevation) adjustment. If we can assume that the mechanical center leaves 25 MOA in the "up" and 25 MOA in the down, then a 20 MOA base will leave the same setup with 45 MOA of "up" and 5 MOA of down.

This is a rather simplistic explanation - but this should answer your question....

[Roger SS]

Any distance where there is 20 MOA of "down" adjustment. Simple answer - but that is the deciding factor, and that depends on the scopes range of adjustment and the final scope mounting to the rifle (IE the setup in total).

Assume (for this example) a theoretical setup where the scope has 50 MOA of vertical (elevation) adjustment. If we can assume that the mechanical center leaves 25 MOA in the "up" and 25 MOA in the down, then a 20 MOA base will leave the same setup with 45 MOA of "up" and 5 MOA of down.

This is a rather simplistic explanation - but this should answer your question....

All that being said, what do you feel would be a good answer to his question? "What is the minimum distance a 20MOA base is good for?" 100 yards?

[Russell D]

I almost always use a 20MOA base and I've only had one instance where I wasn't able to zero my rifle at 100 yards; that is out of probably 10 different cailber and scope combinations. All I did to remedy the issue was I put a .010 thick piece of brass shim stock under the front of the base and all was well. I still have the rifle set up this way and it still holds zero.