AR Scope Mounting: Rings vs Mount

[HairyDemon]

Building a 308 AR, and got a good deal on a Sun Devil Reciever Set. The down side is the set is slick side and comes with no shell deflector bump. so I beleive unless I get lucky and it is gassed right to eject at like 2 oclock. I am looking at installing one of these Case Deflector, for Flattop Upper on the reciever to protect my face in case the ejection gods want to be cruel. I normally use one piece mounts on all of my AR's for scopes, I would like to do a 20MOA mount on this gun since it will be a 308 so I could get enough UP to get to 1K but I can get there with holds. What I am asking is, what are your opinions of using Rings on AR's vs Mounts. I am hoping I can mount this foar enough forward to get eye relief and still make room for the deflector. Seems like alot of variables and all of them cost money and are a pain to return.

Any Suggestions, I was going to mount either a Leupold Mk4 4.5-14x40 or a Vortex PST 2.5-10x32 both have adequete elevation adjustment to get a ways past 500 which is goal for this gun.

Sun Devil Mfg SD308 matched set LR308 receivers : AR15 Parts at GunBroker.com Here is my reciever for visual aid.

Any other south paws out there with ideas.

Moderator.....didnt know if this belonged in the Gas gun area or the Optics.

Thx.
Hairy

 

[ORD]

With some of the longer, .308 AR receivers, you can get away with running standard scope rings (of appropriate height of course) and still get the scope forward far enough so as to give you the proper eye relief/positioning on the rifle. Its tougher with an AR-15 because there is less rail space to get the job done. Whether it will work for you personally will depend on how you position yourself on the rifle (whether you shoot NTCH or further back on the stock), as well as the amount of eye relief that your scope features, and the size of the scope itself. Whether or not regular rings will work will also depend on how much rail space you have to sacrifice for the installation of the bolt-on shell deflector as you have already observed. The Fulton Armory one, at least the one I recall seeing, actually takes up a sizeable amount of space on the rail which might cause you problems. There are others, like the KAC bolt-on deflector for the SR-25/Mk11 for example if you can find one and get it to work, that only take up 2 slots on the rail and may make it easier for you. Here's what the KAC looks like (try not to get sticker shock as with all things KAC): KAC-KNIGHTS ARMAMENT SR-25 SHELL DEFLECTOR There are also things like brass catchers that can be added to cut down on the brass-to-face problems some lefties experience with some gassers.

Just too many variables to tell you whether x- or y- will work for you. Good luck though! Hope you get it sorted out.


ETA: adding an adjustable gas block and tuning how the rifle cycles/ejects is of course, another option so you aren't taking a brass beating when shooting it.

 

[HairyDemon]

With some of the longer, .308 AR receivers, you can get away with running standard scope rings (of appropriate height of course) and still get the scope forward far enough so as to give you the proper eye relief/positioning on the rifle. Its tougher with an AR-15 because there is less rail space to get the job done. Whether it will work for you personally will depend on how you position yourself on the rifle (whether you shoot NTCH or further back on the stock), as well as the amount of eye relief that your scope features, and the size of the scope itself. Whether or not regular rings will work will also depend on how much rail space you have to sacrifice for the installation of the bolt-on shell deflector as you have already observed. The Fulton Armory one, at least the one I recall seeing, actually takes up a sizeable amount of space on the rail which might cause you problems. There are others, like the KAC bolt-on deflector for the SR-25/Mk11 for example if you can find one and get it to work, that only take up 2 slots on the rail and may make it easier for you. Here's what the KAC looks like (try not to get sticker shock as with all things KAC): KAC-KNIGHTS ARMAMENT SR-25 SHELL DEFLECTOR There are also things like brass catchers that can be added to cut down on the brass-to-face problems some lefties experience with some gassers.

Just too many variables to tell you whether x- or y- will work for you. Good luck though! Hope you get it sorted out.


ETA: adding an adjustable gas block and tuning how the rifle cycles/ejects is of course, another option so you aren't taking a brass beating when shooting it.

Roger that ORD,

I already was planning on Rifle Gas system and adjustable block, but I just wanted to have defence in depth. I am kinda attached my my right eye, even if it isnt my dominant one!