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Discussion Starter · #1 ·
Hi Everyone,

I have a Millett DMS-1 on backorder from Midway. I'm looking at scope rings: specifically the Burris Xtreme Tactical. They come in 4 different heights: 0.25", 0.5", 0.75", and 1". I was thinking the 0.25" or 0.5" would be the best choice.

Anyone have any thoughts?

Thanks.

Regards,
Crashy
 

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I'd think your objective bell should clear, but that's something to check for first......

I like mine centered on 1.140". That's to the center of a 30mm tube. That corresponds to a center on the half inch (a touch over technically).
 

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Discussion Starter · #3 ·
Hi Bravo,

Thanks for the reply.

The bell diameter is 42mm. So with 0.5" ring height that would leave about 1/4" between the objective bell and the base of the rings. That sounds a little close. Burris has a set that's 0.75" from bottom of ring to base of scope which would put the center of the scope at about 1.34" above the rail. That seems high. Millett also offers rings that are 0.62" from bottom to base. That would put the center of the scope at 1.21" above the rail. Hmm. That seems like the best option, but they didn't get as good a review as the burris and cost about the same.

Any chance I could co-witness?

Regards,
Crashy
 

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Just thought of something..... the 0.55" I mentioned was for a 30mm optic. A 1" optic would have to be slightly taller to be at the same center.

Doing the math, I get 0.64" as the deck-to-tube height that would correspond to mine. In other words, 0.75" would be high, 0.5" would be low.

Sorry.....
 

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Discussion Starter · #6 ·
Hi Bravo,

Isn't the outer diameter of the scope 30mm? So doesn't the original calculation apply?

How significant is .1" or .2"? Will I have to crank the adjustment knobs a lot if I'm not at the optimum height?

What do you have mounted on your XCR?

Thanks.

Regards,
Crashy
 

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My red dot is mounted in a Burris ring and I use the 3/4. I had used the 1/4 and it was very nice but would not co witness. With the 3/4 I have direct co witness. For the Millett, I would go with the 1/2 or the 3/4 based upon which is most comfortable for you. If you like a tighter cheek weld, I would go with the 1/2.

The 1/4 gives a great cheek weld but I am not sure the scope would clear.

Since it is a magnified scope, co witnessing won't work regardless. The best would be to quick released the scope and then go to irons.

The threads on the Burris rings are 1/4-20 so any wing nut or knob from the hardware store will work on the cheap. I had the local gunsmith make me a thumb nut and it works great.
 

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Look at my gun under (xcr light-sights-fixed power or adjustable power) That is the .50" Xtreme rings with a Burris short mag scope (35mm bell dia.)
 

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Yes, the outer diameter of the scope is 30mm. If the axis is fixed, the deck is fixed, then the first calculation was off by half the difference between 30mm and 1". About 0.09".

I'm not sure how significant you'll find .1", it's a matter of cheek weld, and that's a personal preference. I'll say right off though that I was "old school" on the M14 and Garand, so I find the M16 a high cheek weld for me. If you like the feeling of an AR15, then you might even want a higher mount.

The measurement from the line of sight to the deck of an AR is 1.410". My Aimpoint M3 in the LaRue M68CCO is 1.140" off the deck - I find the stock on the XCR lower than the AR, but that's possibly just me.

As far as cranking knobs, I wouldn't be concerned with that in the least - it's more a matter of sight offset than adjusting the scope.

Hope that helps!
 

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Your objective should clear the rail. After that get a comfortable and consistant cheek weld and mount the scope to your eyeline. I can't be more specific as I don't know the measurements of your head, neck and cheek-eye gap, but a good gunsmith should help you play around until you get a good fit.
 

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Discussion Starter · #12 ·
Thanks for the replies.

From what everyone is saying the 1/2" to 3/4" high rings will work. Just whichever is more comfortable for me.

I guess I'll get a few different heights and return the ones I don't use.

Regards,
Marc
 
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