Rifle Scopes Flat Top Ring Height for HDMR Scope

[AR-180]

What height rings do you guys recommend?

It is a lot of scope for an AR. It initially will get used on an LR-308 and a Grendel. Depending on how I like the scope, it could get moved to a .260 bolt gun.

Thanks for your input.

 

[lma]

Re: Flat Top Ring Height for HDMR Scope

You can't use the same rings unless your bolt gun has a VERY high comb.
ARs need special rings like Warne Maxima Tactical Rings 1" for AR15 Flat tops, they are VERY high but give proper head alignment and cheek weld. On a bolt gun, you want them just high enough so the objective bell will not touch the barrel.

Note the difference:

 

[AR-180]

Re: Flat Top Ring Height for HDMR Scope

I totally understand about the different height needed for bolt guns and gas guns.

My question is how high I should go to put a 34mm tube with a 60mm bell onto a flattop. I have worked out the math. I am just trying to decide between rings and an America Defense mount.

 

[Drifter™]

Re: Flat Top Ring Height for HDMR Scope

On an AR flat top, it's more about getting the right height for the centerline of the scope tube. Properly set up for most people in most applications, this height will be sufficient to clear a scope with a 50mm objective lens (~60mm bell).

In most cases, the centerline tube height should be in the neighborhood of 1.5". Height of mounts specifically for the AR will vary slightly by manufacturer, and may vary slightly dependent upon tube diameter. But all will likely be within ~0.1" of 1.5".

Individual rings will work also. But it's suggested to mount both rings to the upper receiver, and avoid mounting the front ring on the handguard (unless it's a true monolithic design where as upper receiver and handguard are one piece). Be aware that turret location on a scope could potentially prevent the scope from being mounted far enough forward for proper eye relief when restricted by the front ring mounted on the upper receiver. If the scope will allow both rings to be mounted on the upper receiver, and at the right height with proper eye relief, any quality rings should serve fine.

AR-specific cantilever-style mounts take all of the variables into consideration, thus eliminating calculations and guesswork in most cases.

Scroll down to near the bottom of this link to see an HDMR mounted on an OBR rifle in an OBR mount:

http://www.ar15.com/forums/t_2_219/18239...tml&page=20

If you're seeking something that will work on both a bolt rifle and AR without having to remove rings, a cantilever picatinny riser for the AR can also work. They are usually around 0.5" to 0.625" in height, so ring height would need to be adjusted to reach the overall ~1.5" goal. Then you would need to determine if that ring height would also work on your bolt rifle.

 

[AR-180]

Re: Flat Top Ring Height for HDMR Scope

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Drifter_1</div><div class="ubbcode-body">On an AR flat top, it's more about getting the right height for the centerline of the scope tube. Properly set up for most people in most applications, this height will be sufficient to clear a scope with a 50mm objective lens (~60mm bell).

In most cases, the centerline tube height should be in the neighborhood of 1.5". Height of mounts specifically for the AR will vary slightly by manufacturer, and may vary slightly dependent upon tube diameter. But all will likely be within ~0.1" of 1.5".

Individual rings will work also. But it's suggested to mount both rings to the upper receiver, and avoid mounting the front ring on the handguard (unless it's a true monolithic design where as upper receiver and handguard are one piece). Be aware that turret location on a scope could potentially prevent the scope from being mounted far enough forward for proper eye relief when restricted by the front ring mounted on the upper receiver. If the scope will allow both rings to be mounted on the upper receiver, and at the right height with proper eye relief, any quality rings should serve fine.

AR-specific cantilever-style mounts take all of the variables into consideration, thus eliminating calculations and guesswork in most cases.

Scroll down to near the bottom of this link to see an HDMR mounted on an OBR rifle in an OBR mount:

http://www.ar15.com/forums/t_2_219/18239...tml&page=20

If you're seeking something that will work on both a bolt rifle and AR without having to remove rings, a cantilever picatinny riser for the AR can also work. They are usually around 0.5" to 0.625" in height, so ring height would need to be adjusted to reach the overall ~1.5" goal. Then you would need to determine if that ring height would also work on your bolt rifle.</div></div>

Thanks, Drifter_1. I went with the ADM Recon.