Weaver™ Style vs. Picatinny Bases
November 19, 2009 at 12:28
Whether you call it Weaver™ style, cross slot, Picatinny, 1913 mil-std
or scope rail, often there’s some confusion about these scope mounting
systems. Are they the same? Are they similar? Will my Picatinny rings
fit a Weaver style base? That’s easy…in the order asked above, no, yes
and definitely maybe.
Are they the same? No. The two scope mounting systems were standardized
at different times, and I suspect the Weaver style strongly if not
almost entirely influenced the Picatinny design.
Are they similar? Yes. When looking at each base head on, they are
almost identical, and for scope mounting purposes, those dimensions are
interchangeable. When viewing the base from the side, that’s where the
critical difference comes to light.
The main difference? The cross slots on the base that the recoil lug or
bolt on the rings fit into are wider on the Picatinny system than on
the Weaver style system. Also, Picatinny specifications call for even
spacing of the cross slots, where the Weaver style system does not
have that specification and a few slots are often placed where it best
suits mounting a scope.
Will my Picatinny rings fit a Weaver style base? Maybe. If the recoil
lug in the rings is small enough, they may work with a Weaver style
base, but most often they will not. Yet Weaver style rings will almost
always fit Picatinny bases.
If you’re curious enough and want to know, the dimensions for both
styles of bases can be found online and remember, that if you’re using
Picatinny rings, it will be best to find a Picatinny base as well.