Were 1950 era Winchester M70's drilled at the factory? If true

Does The Beuhler adjustable mount use the factory holes.

Yes.
IDK.
Spacing is different on H&H mags.

yea, it's a 300 H&H

Front ring spacing is .860” and rear should be .330” on magnums

richj,
Is there any knurling on the top of your rifle's action?

My buddy sort of inherited this one. I don't recall knurling. I talked him through adjusting the elevation on the Beuhlers mount. The scope is way too forward. The owner was 6'-5" and at one time 400lbs

Yes, all those have knurling; covered up by your scope mount.

They had knurling so as to minimize glare when using iron sights; a relic of the days before good scopes were available. In 1964 it was deleted; certainly had not been necessary for many years, if ever.

I am thinking .330" hole spacing is post 64 H&H magnums; I believe pre 64 are .425" on the rear bridge

airgun1 is correct, .425 spacing in the rear of my 375 H&H.
bb

Something to consider. My .300 H&H is a 1949. When I went to mount a scope I noticed that the rear holes were not perfectly centered. I called Buehler and talked to the man himself, explained the problem and asked if he had a solution. He laughed and said that is why he made undrilled bases for the M70's. Apparently the problem was common enough to warrant keeping the undrilled bases in stock. So if you are going to change mounts make sure of the alignment and spacing.
C.G.B.

A 1949 H&H magnum could be found undrilled, one hole drilled or both holes drilled on the rear bridge. If not drilled properly, I will wager that Winchester didn't drill it.

That could be, no way for me to tell. It has been a wonderful rifle.
C.G.B.

The rifle above is 1951.

This is from Kinks.

49a - Win M70 375/300 H&H only
Len= 1.058

47 - Win M70
Len = 1.168
Spacing = .860

I measured my M70 375 from 1959.

the rear hole is outside to outside .554 - .120 = .334+,-

I have now a mod. 70 pre 64 fwt in 3006, and had mod. 70s pre 64 in 300 H&H and 375 H&H, I still have the Buehler bases and rings,some on guns and some still waiting..Same with old Redfields, and it appears since all mod 70 back in the day were the same length that I used all these on different mod 70s so they seem to be the same length and hole spacing. I think they are factory drill and tap...correct?? It seems to me I recall some had two holes in front and one in the rear ring and I have Redfield bases with 3 holes to match, maybe some Buehlers? indicating some actions came with 3 holes??? Im a bit vague here because I have boxes of such stuff and its usually try for hole spacing, and use the one that fits with a bore sight. In some cases the bases are marked on the bottom.

Your measurements are close but your math skills are lacking. .554-.120= .434

Also the Weaver 49A base has three holes. One pair is .330" for post 64 H&H and the other pair is .425" for pre 64 H&H

quote:

Originally posted by richj:
The rifle above is 1951.

This is from Kinks.

49a - Win M70 375/300 H&H only
Len= 1.058

47 - Win M70
Len = 1.168
Spacing = .860

I measured my M70 375 from 1959.

the rear hole is outside to outside .554 - .120 = .334+,-