Scope ring location

[Droppin Deuces]

Is there any reason NOT to mount a scope with one ring attached to the receiver and the other attached to the RIS? I have mine set up that way and have never had any accuracy issues that I'm aware of, but it recently occurred to me that I've never seen pictures of a scope mounted that way. Now I'm self-conscious about it.

[Droppin Deuces]

Any gun I see with the same type of scope always seems to have the same mount:

http://img189.imageshack.us/img189/1858/meopta1x4rd005mv9.jpg

Why is this used as opposed to direct mounting to the receiver and front end?

[FMJBT]

Even with the most rigid forend setups, there is still a slight amount of flex between the receiver and forend. Having a ring mounted on either component will essentially make the scope a stressed member of the assembly. Any flex induced on the forend will be transmitted directly to the scope tube. Most scopes are designed to withstand tremendous forces of recoil, but not so much lateral or bending forces. You can end up with lenses popping out of place, dimples in the scope tube, etc. It's best to just use a forward offset mount like the Larue SPR or American Defense RECON to mount the scope to the proper eye relief setting. Either that or go with a monolithic platform upper receiver where the receiver and forend are a single piece of metal.

[Droppin Deuces]

Even with the most rigid forend setups, there is still a slight amount of flex between the receiver and forend. Having a ring mounted on either component will essentially make the scope a stressed member of the assembly. Any flex induced on the forend will be transmitted directly to the scope tube. Most scopes are designed to withstand tremendous forces of recoil, but not so much lateral or bending forces. You can end up with lenses popping out of place, dimples in the scope tube, etc. It's best to just use a forward offset mount like the Larue SPR or American Defense RECON to mount the scope to the proper eye relief setting. Either that or go with a monolithic platform upper receiver where the receiver and forend are a single piece of metal.

Makes a lot of sense. Guess I'll start looking for a mount.

Thanks so much for the reply.

[killshot44]

I've done the shopping already, might as well share it: http://swfa.com/Burris-AR-PEPR-30mm-...nt-P12623.aspx

Works like the Larue for $70...

[Droppin Deuces]

^^^ Ah, perfect! Will match up nicely since I'm already using the XTR "xtra high" version.

http://www.burrisoptics.com/jpg/XTR_rings.jpg

Thanks a lot!

Going back to what FMJBT said, I'm wondering if having the quad rail actually pinned to the receiver would be considered "monolithic"? I'm assuming yes. The thing is absolutely rock solid.

[FMJBT]

^^^ Ah, perfect! Will match up nicely since I'm already using the XTR "xtra high" version.

http://www.burrisoptics.com/jpg/XTR_rings.jpg

Thanks a lot!

Going back to what FMJBT said, I'm wondering if having the quad rail actually pinned to the receiver would be considered "monolithic"? I'm assuming yes. The thing is absolutely rock solid.

Probably depends largely on the type of forend, and the method of pinning. I still dont think it could be made as strong as a truly monolithic upper receiver though. Any attached forend will still have the joint at the barrel nut that will act as a fulcrum when bending forces are applied. All impact or bending forces will end up acting upon the threaded portion of the upper receiver via the barrel nut/forend. A true monolithic receiver will spread those same forces across the entire length as the forend is not mounted by the barrel nut. The length of the forend will also play a part, as a longer rifle length forend will allow more leverage and bending force to be applied than a shorter carbine length rail. Some designs are more inherently rigid than others as well. The Daniel Defense Lite rails have a very strong mount to the upper receiver, but I would still hesitate to bridge the gap between the two with an expensive optic....

Another option is to add a riser mount across the surface of the receiver and forend, effectively "monolithanizing" (I think I just made up a new word. Yay!) the two parts together. Something like this:

http://www.pri-mounts.com/mm5/merchant.mvc?Screen=PROD&Store_Code=PRI&Product_Code=05-073-06&Category_Code=FOREARMS

[Droppin Deuces]

Ok, fine, I'll spend the $$$ and do it right...

Thanks again, guys. You've been a huge help as always.