Poorly drilled and tapped: fixes?

mwjones

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I have a rifle that I purchased drilled and tapped for scope bases with some little aluminum weaver mounts attached. Imagine my dismay when I mounted some rings, and could not get the scope to sit in the rings properly. I tried flipping the rings backwards, front to back, and it wouldn't sit right. Waitaminute, i thought, maybe it's the bases! Closer inspection revealed that not only are the holed drilled and tapped off center, but not aligned to each other so that there is a bit of an offset, like so:

scopeholes.jpg

(Please forgive my crude paint drawing. black is reciever, blue is center line, red is screw holes)

I have come up with a couple of solutions that may work, but was wondering if anyone else had any ideas.

Solution one: Rings that are adjustable for windage AND cant/twist. I was looking at some millet rings, but they only adjust for windage, which will only solve half of the problem. Anyone know of any rings available that can be adjusted so both rings run in a straight line?

Solution 2: File the bases so that they are straight when mounted. A little labout involved, but with repainting they should look okay. I'm worried about the stability of the scope, however, and that my rings may not attach securely with a slightly wonky/undersized base.

Solution 3: Buy a one piece base, use the two best holes, and cross my fingers. Or, buy bases (one or 2 piece) without predrilled holes, and purposely drill the holes off center to fit the holes in the reciever. I can't find any bases without holes that already have the channel cutout underneath for the reciever/barrel. I would rather not have to mill the channel.

Solution 4: Drill and tap more holes. This would definitely work, though i won't really like the swiss cheese look, even with grub screws filling the old ones. The gun is semi collectible (I know, not drilled and tapped it isn't) and I want to keep from bubbaing it further. There's also a small chance, though unlikely, that i may end up with more buggered holes.

Anyway, those are my ideas. Any thoughts?
 
I had a friend that had the same problem. His had the Weaver two piece bases. I told him to buy Burris Signatue Zee rings and a set of the offset inserts. It worked quite well for him.....Ken

should work, as long as the deviation is not too much to overcome with the inserts. According to your diagram, your holes seem way out of whack (that's what she said...)
 
I've done this a several times. I used RED loctite on a screw, install and let it cure. Carefully file off the screw so it is flat/flush with the action. If you're really carefull it can hardly be seen. Then redrill/tap to whatever you want. I've never had any issues with overlapping of the hole/tapping/theading.
 
I was wondering if loctite would be strond enough to hold the old screw while drilling and tapping a new hole... The diagram isn't exact. All 4 holes would be in this situation, as not one of them is off by a full screw width.
 
If I recall all of the holes I had to redo were drilled/tapped about 1/2 way across the old hole and yes the loctite held without any trouble. I did use a bushing/base as a guide for the drill and did the job sllooowwly with good cutting oil. The above replys about using Burris rings are good advise as well, I've used them and they are very good. Its been a few years since I redid the drill/tap jobs but I don't recall any special problems, all worked out OK. If it were in a big $ gun the Dans idea about welding is good. 2 of the guns were Ruger 10-22's (aluminium) at least 1 303 Lee Enfield and I can't recall the rest.
 
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