When did companies start drilling and taping rifles to a standard.


A lot of rifles are 0.504 hole spacing. I'm guessing that Weaver had something to do with it.

That makes some sense, Rich, but as with most other brands early on Weaver seemed to use side mounts or put one base on the barrel. The only real contender I can think of is Redfield, which introduced its JR mount in 1928.

Stroebel calls it the "Junior Mount" and dates it from the mid-'30s but I suspect he nodded there, too. Why? Because I found an ad from 1971 extolling their founder, John Redfield, and that invention of his. It's not explained but my guess is the JR comes from his initials.

And though I'm rueful of Redfield's part in introducing image-movement, I love the JR mounts and have used them for 40 years with no regrets.

Redfield is older; 1909 vs 1930 for Weaver. However, Weaver developed the two piece bases and ring system that were cheaper, and more versatile. Which is why they became so popular. Even the Army made use of that system, calling it the Picatinny rail. I worked with the engineers at Picatinny Labs so won't comment on them.

I have a set of JR mounts, forget which rifle they fit.

Looking further afield, I see that Redfield ads did sometimes use the term 'Junior' to describe their JR mounts, at least after those initials were limited to the one-piece base and the two-piece ones got termed SR. Why they would have demeaned the original product initials as meaning Junior escapes me, though, as they are not a style I would think meant for .22RFs.

Weaver's use of the base rail appears to not have begun until after WWII, however, about 20 years after the Redfield JR. Most other brands of receiver-top bases also dated from the 1950s. I have not been able to confirm that the early JR bases came with pre-drilled holes, though.

Winchester's mounts had required some kind of dovetail beneath them at least as far back as 1909 but it seems they did not drill and tap receiver tops as standard until the M70 came along. That could suggest hole distances were settled before the war, though.

I have a set of "FR" Frontier/Redfield bases for a Browning BAR.

small dovtail with a tapered shoulder and 2 pillars.

Yes, FR was the third type in the series, launched in the 1970s according to Stroebel. You'd think that had the earlier ones really been intended to be read as Jr and Sr, the Frontier would have been dubbed III

The Frontier mount was intended for scopes with long eye reliefs, of course.