Are Picatinny And Weaver Bases The Same Size?

UtopiaTexasG19 · December 21, 2011, 07:23 PM

Will a scope mount that mounts to a picatinny rail also fit a Weaver rail?
I have a old 1x4 scope I took off my AR last year and am planning on mounting it to my Marlin 336. The only flat rail I can find for the Marlin 336 says it is a Weaver style. Thanks...

NYCShooter · December 21, 2011, 10:29 PM

Not likely. Generally, a device designed for a Weaver rail will fit a Picatinny rail, but one designed for a Picatinny rail will not fit a Weaver rail.

saands · December 22, 2011, 04:43 PM

I think that the most accurate answer to your question is MAYBE.

The cross section of the Picatinny and the Weaver rails is compatible (if not the same), but the cross cuts are larger on the Picatinny than on the Weaver, so if the original scope was actually DESIGNED for the Picatinny, then it won't fit on a Weaver, but if all you know is that it happens to FIT on a Picatinny, then it very well might fit on the Weaver as well. Very few non-mil-spec mounts are actually sized to the larger Picatinny spec. ... if in doubt, just measure the cross bolts on the scope you have and see. For reference, “mil-spec” Picatinny rails will have a grove width of 0.206″ while Weaver rails typically have a narrower, 0.180″ groove width. One other complication is that if the rings on the scope can't be moved fore and aft on the scope, then the spacing of the slots on the Weaver rail might not match.

Saands

AK103K · December 22, 2011, 05:45 PM

I had this problem with my Springfield SOCOM. The "mil spec" mounts (ARMS and LaRue to be specific) I had for my AR's and AK's, didnt fit the SOCOM's rail properly.

The ARMS mounts would go on, but not stay, or even draw up tight. The LaRue would not go on at all, as it has a "double block" in its base that didnt fit the rails slot spacing. The ARMS mounts/rings only have one block, and arent dependent on the spacing. I was able to "fool" the rings by setting them against the edge of a block in the slot, fore and aft, so they would not move whe the scope was installed. That seemed to work OK. The problem with the Aimpont rings was, the clamp would not draw up tight (the rings didnt either), and the mount would move in the slot under recoil.

Weaver mounts and rings worked fine, in all respects, which leads me to believe Springfields mount was a "Weaver", although they repeatedly swore it wasnt when I called and asked.

I found this on Brownells site, may help explain it better..

http://www.brownells.com/.aspx/lid=1...he_Difference_

UtopiaTexasG19 · December 22, 2011, 06:34 PM

Here is what I am doing which prompted my original question. I had a Primary Arms 1x4 scope with the Primary Arms extended reach scope mount on my
AR15 which has the quad picatinny rails. I decided to start shooting a lot further out and eventually put a Nikon 3x9 on the AR15 and now want to put the Primary Arms Scope and scope mount on my Marlin 336 in 30-30. In my intial search of gun parts sites I found a nice flat rail to mount on the Marlin but everything I found was in the Weaver style so I was wondering if the picatinny scope mount might fit the weaver style rail. I have since found a nice flat top rail for the Marlin in picatinny style so when it arrives do not expect any problems. Thanks for all the replys!

December 21, 2011, 07:23 PM	#1
UtopiaTexasG19 Senior Member Join Date: July 3, 2011 Location: S.E. Texas Gulf Coast Posts: 743	Are Picatinny And Weaver Bases The Same Size? Will a scope mount that mounts to a picatinny rail also fit a Weaver rail? I have a old 1x4 scope I took off my AR last year and am planning on mounting it to my Marlin 336. The only flat rail I can find for the Marlin 336 says it is a Weaver style. Thanks...

December 21, 2011, 10:29 PM	#2
NYCShooter Senior Member Join Date: October 2, 2009 Posts: 103	Not likely. Generally, a device designed for a Weaver rail will fit a Picatinny rail, but one designed for a Picatinny rail will not fit a Weaver rail.

December 22, 2011, 04:43 PM	#3
saands Senior Member Join Date: November 14, 1999 Posts: 1,573	I think that the most accurate answer to your question is MAYBE. The cross section of the Picatinny and the Weaver rails is compatible (if not the same), but the cross cuts are larger on the Picatinny than on the Weaver, so if the original scope was actually DESIGNED for the Picatinny, then it won't fit on a Weaver, but if all you know is that it happens to FIT on a Picatinny, then it very well might fit on the Weaver as well. Very few non-mil-spec mounts are actually sized to the larger Picatinny spec. ... if in doubt, just measure the cross bolts on the scope you have and see. For reference, “mil-spec” Picatinny rails will have a grove width of 0.206″ while Weaver rails typically have a narrower, 0.180″ groove width. One other complication is that if the rings on the scope can't be moved fore and aft on the scope, then the spacing of the slots on the Weaver rail might not match. Saands

December 22, 2011, 05:45 PM	#4
AK103K Senior Member Join Date: May 1, 2001 Posts: 10,223	I had this problem with my Springfield SOCOM. The "mil spec" mounts (ARMS and LaRue to be specific) I had for my AR's and AK's, didnt fit the SOCOM's rail properly. The ARMS mounts would go on, but not stay, or even draw up tight. The LaRue would not go on at all, as it has a "double block" in its base that didnt fit the rails slot spacing. The ARMS mounts/rings only have one block, and arent dependent on the spacing. I was able to "fool" the rings by setting them against the edge of a block in the slot, fore and aft, so they would not move whe the scope was installed. That seemed to work OK. The problem with the Aimpont rings was, the clamp would not draw up tight (the rings didnt either), and the mount would move in the slot under recoil. Weaver mounts and rings worked fine, in all respects, which leads me to believe Springfields mount was a "Weaver", although they repeatedly swore it wasnt when I called and asked. I found this on Brownells site, may help explain it better.. http://www.brownells.com/.aspx/lid=1...he_Difference_

December 22, 2011, 06:34 PM	#5
UtopiaTexasG19 Senior Member Join Date: July 3, 2011 Location: S.E. Texas Gulf Coast Posts: 743	Here is what I am doing which prompted my original question. I had a Primary Arms 1x4 scope with the Primary Arms extended reach scope mount on my AR15 which has the quad picatinny rails. I decided to start shooting a lot further out and eventually put a Nikon 3x9 on the AR15 and now want to put the Primary Arms Scope and scope mount on my Marlin 336 in 30-30. In my intial search of gun parts sites I found a nice flat rail to mount on the Marlin but everything I found was in the Weaver style so I was wondering if the picatinny scope mount might fit the weaver style rail. I have since found a nice flat top rail for the Marlin in picatinny style so when it arrives do not expect any problems. Thanks for all the replys!