OK first this is my fathers 30-06 ser # is 13,xxx( yes very low) it has a scope which he wishes to replace. The scope on it now has a redfield one piece base and rings. The redfield base will not take new rings rear screw grove is different, old rings are not 1". So he ordered a new Redfield onepiece base and rings and here is another problem. The two front holes line up prefect but the rear hole is off by .030" or so. I know there is probably some way around this but he would like to keep the Redfield base.

What is the fix here???

Is the ser# so low that the hole spacing was changed??? From what I can tell the old Redfield base is unmodified ( like the gunsmith miss drilled the base and just adjusted the hole) the old base looks perfect.

No he is not interested in selling the rifle to someone else who would be willing to solve or live with the problem.

RNS

I am certainly not an expert here, but I will pass on a bit of knowledge I picked up --------- there are 2 different spacings for the rear screw holes on a 70. A large one-- which is "standard" these days and a "short" .330 spacing that was made for magnum length actions pre 64. I would check the spacing on the screws. I am guessing that it is .330 and you can use the magnum set-up. If thats not the case----sorry, just trying to help.

Wouldn't this be a simple matter of replacig the two rear windage screws provided they have the same threads as the old? That is the groove you're talking about, right?

Zach - The heads of the old windage screws are smaller than the current design. He is referring to the circular "groove" that is machined into the sides of the base. I know this because I have an pre-war M70 base with a bent windage screw and can't find a replacement.

Oops.

Aarghhh!

Gotcha.

I was thinking about his statement that the groves in the rings did not match. Failed to think about the corresponding groove in the base.

Aren't blank, undrilled bases available? A decent gunsmith could then drill the bases to match....

The easiest and quickest fix as someone already mentioned is to buy an undrilled base and have a gunsmith drill the base to fit. Measure the hole spacing and call Redfield, they might have one or make one too. Please don't drill anymore holes in that beautiful prewar action, it already has one too many! The other route is to find a vintage Redfield base like the old one with 1" rings instead of the 7/8" rings which I'm guessing are what you have. I may have one laying around if you send me a PM with the measurements. Just curious, is the old scope a Lyman Alaskan or Weaver 330?

here is some info and pics

http://www.accuratereloading.com/ubbthreads/showflat.php?Cat=&Board=UBB5&Number=218197&Forum=,f5,&Words=&Searchpage=1&Limit=25&Main=218190&Search=true&where=bodysub&Name=1773&daterange=1&newerval=2&newertype=y&olderval=&oldertype=&bodyprev=#Post218197

RNS, Good grief! The pre war spacing from rear receiver ring screw to the one bridge screw was most likely 4.100, some were 4.093. Space between front scope ring socket and clamp area for the rear scope ring should be the same as the replacement base. Width of old rear ring was about half that of front ring. Rear base-depending on when it was made could have a step down corresponding to the end of the old ring. The screws had a different head diameter and thread.
Head was about 11/32 diameter and thread most probably on your base was 8 x 40. The cone angle inside the windage screw heads where they clamp the ring is the same cone angle and will have the same effective clamping force as those on the new base even if part of the rear scope ring hangs over a step down in the old base. Can we assume that the front ring turned into the socket for it in the old base and that your concern ( or some of it) was the gap between edge of screw head diameter for original base screws and those fingernail clipping (in appearance) machine cuts on the new ring? Cheapest and nicest appearing way out is to open up the old base threads for the windage screws to 3/16x 32 and turn the head diameters down to fit the counter bores for them in the base if that is still a matter of concern.

I'm sure I have a old Redfield base that will work for you. I might even trade you the base for the rings...email me and lets see what we can do...I will need the specs...