Rifle Scopes Which brand and what height of 1" rings for a low cheek weld on my new 18" bbl AR15 with 40mm scope?

[charliebrown1999]

Need help from anyone experienced with mounting a 40mm objective lens 1" tube scope on an AR15 SPR. I want the lowest tightest cheek weld and a light weight AR15 so I what to use rings instead of a one piece mount. Also my AR15 will not be wearing iron sights so no co-witnessing with BUIS. I know that rings will get the scope closer to the center of the bore axis but which ones??? I intend to mount a Leupold mark AR mod 1 4x12x40 AO with P5 turret and 1" tube SKU 115392. I have been looking at Burris XTR 3/4 inch high rings. Are there other better choices???

 

[wade2big]

You won’t be able to use rings on an AR. You want the scope mounted on the receiver only. With rings you will have to mount one ring on the handguard. Not good. You will need an offset one peice. Google pics of AR15 with scopes and visualize where the front ring would have to be mounted and you will see what I mean.

 

[Hollywood 6mm]

You won’t be able to use rings on an AR. You want the scope mounted on the receiver only. With rings you will have to mount one ring on the handguard. Not good. You will need an offset one peice.

Totally depends on the scope and eye relief. There's plenty of setups with rings on an AR without mounting to the handguard. That said, a single piece mount is the better way to go on an AR.

@charliebrown1999 - you'll want 1.4-1.5" height, and ideally a single piece mount. Anything lower and you risk not being able to get a good sight picture through the optic. Getting your scope as low to the barrel as possible isn't critical - good sight picture and eye relief through the optic is.

 

[wade2big]

Totally depends on the scope and eye relief. There's plenty of setups with rings on an AR without mounting to the handguard. That said, a single piece mount is the better way to go on an AR.

@charliebrown1999 - you'll want 1.4-1.5" height, and ideally a single piece mount. Anything lower and you risk not being able to get a good sight picture through the optic. Getting your scope as low to the barrel as possible isn't critical - good sight picture and eye relief through the optic is.

It would have to be a very short eye relief and the stock would need to be fully extended unless I am missing something.

 

[Hollywood 6mm]

It would have to be a very short eye relief and the stock would need to be fully extended unless I am missing something.

Or a really short optic. Like I said, a single piece is ideal, but rings can work depending on the exact optic, etc.

 

[wade2big]

Or a really short optic. Like I said, a single piece is ideal, but rings can work depending on the exact optic, etc.

He states the exact optic he will use. Wont work. I could be wrong but I dont think so. I would use rings as well if I could. I dont care for one peice mounts that attach to pic rails.

 

[spife7980]

Id be more interested in why he wants the scope as low as possible considering that the buffer tube will be exactly where his face needs to be behind the scope unless he has no cheek bones.

I find less than 1.4" tough to even see though in any configuration much less be comfortable.

 

[Hollywood 6mm]

He states the exact optic he will use. Wont work. I could be wrong but I dont think so. I would use rings as well if I could. I dont care for one peice mounts that attach to pic rails.

To be clear, I was making a general statement, not one specific to the OP. One piece mounts are ideal on ARs, and often required, but there are some situations where rings will work just fine.

 

[spife7980]

OP:
Objective diameter fro the markar 4-12x40ao is 2", that means you have 1" minimum below the scopes centerline which you have to overcome, and even more so that the scope isnt touching. Your 3/4" rings comment will obviously not work.

If you have the scope and rifle already then get some cards or something stackable to set on the picaitnny rail and then put the scope on top of. Then see how high you need to stack the cards to be able to properly see through the scope.
Most rings are measured from top of the rail to scope centerline. The 1" tube means that 1/2" of tube is below that centerline which you would need to consider. So if you need 1" of cards to see through the scope plus the 1/2" of tube means 1.5" tall rings. Some measure to the bottom of the tube though so in that case it would just be the 1" measurement of the cards. You need to know how the manufacturer got their listed dimensions to know what the listed dimensions are good for.

 

[charliebrown1999]

OP:
Objective diameter fro the markar 4-12x40ao is 2", that means you have 1" minimum below the scopes centerline which you have to overcome, and even more so that the scope isnt touching. Your 3/4" rings comment will obviously not work.
View attachment 7178851

If you have the scope and rifle already then get some cards or something stackable to set on the picaitnny rail and then put the scope on top of. Then see how high you need to stack the cards to be able to properly see through the scope.
Most rings are measured from top of the rail to scope centerline. The 1" tube means that 1/2" of tube is below that centerline which you would need to consider. So if you need 1" of cards to see through the scope plus the 1/2" of tube means 1.5" tall rings. Some measure to the bottom of the tube though so in that case it would just be the 1" measurement of the cards. You need to know how the manufacturer got their listed dimensions to know what the listed dimensions are good for.

Thank you for the illustration and information. I appreciate you sharing your knowledge.

 

[RFutch]

NightForce 1.125” mount with ring reducers off Amazon. Lowest thing I could find and it’s about perfect for me.

 

[M8541Reaper]

Id be more interested in why he wants the scope as low as possible considering that the buffer tube will be exactly where his face needs to be behind the scope unless he has no cheek bones.

I find less than 1.4" tough to even see though in any configuration much less be comfortable.

I was running an LT807 with a MK6 3-18x44 on an LMT. It’s a 1.375” mount and I had to run a CTR w/ a RISR to get proper cheek weld/height.

Lower mounts can be run an ARs, just depends on the type of upper and the ring spacing needed. You can also run rings on certain uppers. If you have a monolithic upper then you have nothing to worry about. Other things to consider are BUIS and their folded height, type of stock, and LOP. I'm about to experiment with an ATACR 4-16x42mm in an LT120, which if it is anything like how I mounted an NXS F1 in rings, it should sit within about a tenth of the MK6 setup. That means I might be able to run with just a SOPMOD or I'd have to toss on the CTR with a RISR. Regardless, don't let peeps tell you it won't work when it will. See what works best for you and the rifle setup game, especially on an AR, is all about experimentation (like college). lol

 

[M8541Reaper]

Also, here is a great resource for experimenting with ring setups:

Scope Ring Height and Clearance Calculator