WTK: Are Weaver and Picatinny rings interchangeable?

Waiting for an answer, I have wondered about this for some time>

i dont think they are the same. if they were why would someone like smith enterprise offer two separate mounts? one weaver and one picatinny.

http://www.smithenterprise.com/0400_Mounts_Rails_Page.htm

Weaver rails are highly variable in rail width and slot width. They are "generaly" the same.

M1913 rails are all the same width with the only variation being in the slot width, some being a little wider that the standard. M 1913 has a standard that must be met. Weaver does not. I have encountered rails that look like they are 1913 but are not. They are always too narrow. If they don't say 1913 they probably aren't.

Weaver rings will fit 1913 rail but 1913 compatable rings usually have a wide stud in the base that will not fit most weaver style rail slots and they will not clamp down enough for the narrow rails.

interchangeable

I have some 1913 picatinny rings on one scope that won't fit on a weaver mount because the crossbolt is to beefy. I'm just guessing but it seems to me that the military spec stuff is made to take a lot more recoil abuse and more constantly than say, a hunting rifle that only gets used occasionally. I do know that the weaver mounts I have will fit on my 1913 mounts. Good question bubba!

Is there a standard?

Is there an established standard for the picatinny and Weaver bases? Or, do they just call them "Weaver" because they can't spell "picatinny"? I have been wondering that myself......

they are NOT the same....

Picatinny rails are slightly wider and the points are slightly deeper than Weaver bases and mounts.

We have had people try to mount weaver rings on an AR15 flattop and they will NOT fit.

For what it is worth Burris told me to just mount the weaver style rings against the forward edge of the 1913 slot because it would hold up to recoil better mounted tight to the front. BTW, when I asked if they had an extension ring so I could mount the Burris scope on my A.R.M.S. mount, they said the mount must be made for red dot type scopes because it was to short to mount a full sized scope, they said the rail had to be 6.5" minimum. It's a nice piece of glass, but Burris puts their turrets well forward of center. Still trying to find a way to make this work. I should have got a Luppie or a Smith mount.