Anyone ever had to shim a base?

[Possum]

I went to the range with my 30.06 Encore pistol and started getting 2" groups.  I was pleased (being the first time shooting this load and pistol) until I tried to adjust the scope up (Burris 2-7x).  I had reached the max so I went to the store and got a shim that goes between the barrel and the base.  These are about an inch long an is mounted at the rear of the base to raise the point of impact.  Therefore, you have to adjust the scope downward when returning to the range.  It worked very well and I had to adjust down about 8".  Question is has anyone ever had to do this and did it hold up.  I shot about 15 rounds today and got 1.5" groups. Seems to be working.

[Robert]

I was putting a scope on a sporterized p-17.  I have two of them and the cut-down is a different shape on both of them.  This one was hitting slightly low, and I put   one thickness of electical tape under the rear base.  It has been fine ever since and is a 1/4 mile tack driver.  I have done something similar with rings before too.  Just a small peice of plastic tape inside  top or bottom of either ring, could save a lot of work and expense.

[MS Hitman]

I shim bases all the time on things such as 45-70s and 300 Win Mags.  Haven't had any problems with them not hoding up yet.  Brownells sells the shims that are drilled to fit different bases if your local store doesn't.  Every 0.001" you shim on 4" spread rings gets you about an !" at 100 yards is what I have found to be the case.

[helobill]

Other option is Burris Signature rings. They make different inserts that can adjust up to 25" at 100 yards (see their web site). Not much more than standard rings either.
Helicopter Bill