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Discussion Starter · #1 ·
Guys, this will be long winded. So follow me here ok.

The issue I see with all AR family mounts is this. The AR-15 / 10 family is designed around the idea of iron sighted battle rifle. Because of this, lessons learned with the M-1 Grand, M-14 and other builds, the AR-15 / 10 has a fixed length of pull for proper sight alignment of the rear sight aperture. Adding a M4 / CAR-15 style stock or any variation of the type, makes this issue worse. The design of the fixed LOP stock to the AR family is so the rifle can fit all sizes of Soldiers, Marines some Sailors and very few Airmen.

Some would also say the charging handle is the size it is as an index point so you will always have the same eye to rear-sight aperture distance for the same sight alignment. Also why there are two sides to the charging handles finger engagement pads.

We as a group of shooters that SHOULD understand the fundamentals of marksmanship; understand the level of accuracy gained with a proper cheek weld to stock and agree with this training point of a index point on a rifle to gain cheek weld and the same sight picture. No matter the sighting system be it, a rifle scope or open sights.

Since the start of the A3/A4 upper receivers the AR-15 / 10 rifles work best with a non-parallax optics @ 50yds and beyond aka EO-Tech's, AimPoints and the like, because the LOP and the index point as a training point still work. With a magnified optic that is a parallax induced riflescope; this original design has been and still can be a bastardization effort to make the sighting system work just right.

So what I ask is this, if a new mounting platform is to be designed, I would go from the start of it all. I would measure the height of the rear aperture from the stocks comb and the distance forward of the rear location of the receiver and make that the focus point of any and all optics, no matter the tube size, eye relief or MOA built in the base it's self.

With the measurement of the A-15 A1/A2 upper receivers rear aperture sight location from up and forward the axis point is now found for all optics, that gives the best cheek weld. I say this because how many people can not get a cheek weld on a AR-15 A1 or A2 iron sighted rifle? In my days as a 11B, no one, male or female had a issue. Big or small, different cheek to eye socket distances made no difference. They all could use the rifles sights.

But add in Brand X optic mount and Brand X rifle Scope, "well it fits me, but not you" Or why is this optic so low? Or why does this scope shadow" and the best, I need a cheek weld riser!!!!!!!

Almost every mount except the Larue SPR-E and the ADM Recon has the rear of the optic with the option of being even with the charging handle. So because of this, it makes the shooter short stock the Length of pull to get the proper eye relief. I think this measurement as a focus point will stop the short stocking, and the goose necking to get the eye relief needed, and / or a 45 degree off set of a shooters core to the prone position. Also this makes sitting a joke, standing a pain in the A$$ and all other up side down, backwards positions not work.

So here is a base picture of my idea.



Ok, with that, what good does this mount do for you?



Or this one:



How about this?



Or



Any of these?







All of these are made by great company's, all of them hold a optic to the upper nice and tight, to bad you got to have a jacked up shooting position to use them.

Now lets look at the other direction.





Or if you NEED MOA Slope



And that base intern does this:



I get so sick of seeing people working there A$$ in the ground, spend that money and buy CRAP that does not do the job they need there parts to preform!!!!!!!

WHY?

Rant off

John
 

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I agree.

That darned receiver is 4-6" too short in front and 1/2" too low for optics on standard mounts.
 

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Well put. I know it sucks paying almost $200 just for a scope mount, but the Larue and ADM Mounts do put the scope in the ideal location.

Ideally, when shooting the AR, it is best to use the Nose-to-charging-handle position (NTCH) whenever possible (Your nose should be as close to the charging handle as possible so you obtain the same sight picture everytime.). This is possible with an A1 stock or any collapsible stock. It is very hard to do with an A2 stock unless you have a long-ass neck. When you shoot NTCH, you generally have to move the scope forward quite a bit to get the proper eye relief, which is generally 3.5"-4.5" for most scopes. That is why the extended scope mounts like the Larue SPR-E and the ADM Recon-X mounts are the best choices.
 

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I am ordering an aimpoint and mount from Larue for the Xtreme build and I figure while I am at it I will get the SPR mount to try it out on my hunting upper.
 

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marinesg1012 said:
I am ordering an aimpoint and mount from Larue for the Xtreme build and I figure while I am at it I will get the SPR mount to try it out on my hunting upper.
I'd get the SPR-E mount if you want to shoot nose-to-charging handle.
 

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I normally shoot close to that. Thanks for the tip
 

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GREAT info, John!!!

When I first got into "sport shooting" AR's, I went with Armalite/RRA/what have you, mounts as they were in my "price range". And you are 100% correct about the jacked up shooting position. With almost every shot, I remember doing the positioning "wiggle" to get my cheek weld/position "correct"... It just didn't feel natural. Since going with the SPR and SPR-E mounts, the "wiggle" is a thing of the past. Sure, the price tag can be a bit bitter... But what can ya do? If you're comfortable, accuracy seems to follow suit which makes these mounts a worthwhile investment!

Currently, I have the SPR-E mount on my SBR. I pulled out the scale and found the numbers you listed were VERY close to where my TR21-3 is mounted. On my 18" gun, the cheapo chinese scope has a short eye relief. Yet is still somewhat close to your measurements using a SPR mount.

Question for ya... As you know, the "asian" glass will soon be replaced with a 3-9x40 Accupoint and a Larue mount. My upper is built using a Vltor VIS and has a "seemless" rail all the way to the muzzle end which provides quite a long mounting surface. My "hold" puts me close, but not exactly NTCH. Should I be looking at the "standard" SPR mount, or go with the SPR-E extended version? Your thoughts?
 

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moose-hunter said:
Question for ya... As you know, the "asian" glass will soon be replaced with a 3-9x40 Accupoint and a Larue mount. My upper is built using a Vltor VIS and has a "seemless" rail all the way to the muzzle end which provides quite a long mounting surface. My "hold" puts me close, but not exactly NTCH. Should I be looking at the "standard" SPR mount, or go with the SPR-E extended version? Your thoughts?
Not John here,
but using the VIS gets around the need for special mounts,
as you can slide any scope mount as far forward as you need.
Both the std and E should work fine.
Obviously, you can't go wrong with LaRue.

Your choice may come down to the SPR-E if you have other weapons without the VIS that need the extended drop forward.
But for the VIS weapon only, you may want to save some money and go with Leupold QRW rings.
http://www.swfa.com/c-107-leupold-quick-release-weaver-style-rings-bases.aspx
 

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Discussion Starter · #10 ·
Clint makes a great point, with that upper you have, its up in the air for you. But the key is to get the right height you need now. I am always looking at other stuff to see what might be just the ticket.

You might want to look at the following as a diffrent mounting source since you have a Monolithic Rail.

CLICK ON THE PIC


CLICK ON THE PIC


But if you go with a LaRue mount, you get to place that optic on diffrent uppers, or if things change and that upper gots to go. You still have a optic and mount to use on other rifles.

Just some thoughts.

John
 

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J Boyette, I do not shoot NTCH, actually my nose is about 3" back from the charging handle, I don't have trouble with iron sights but am confused about scopes on ARs. Are you saying that only LaRue or ADM mounts put the center of the scope at the same place as the irons. I have irons on my 5.56 but when my 6.8 gets here it will be a scope only weapon. What I am trying to avoid is buying a bunch of scope mounts that I can't use.
 

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spoonxman said:
J Boyette, I do not shoot NTCH, actually my nose is about 3" back from the charging handle, I don't have trouble with iron sights but am confused about scopes on ARs. Are you saying that only LaRue or ADM mounts put the center of the scope at the same place as the irons. I have irons on my 5.56 but when my 6.8 gets here it will be a scope only weapon. What I am trying to avoid is buying a bunch of scope mounts that I can't use.
The Larue and ADM Extended Mounts put the scope at the proper height and forward enough for the proper eye relief.
 

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J.Boyette said:
Clint makes a great point, with that upper you have, its up in the air for you. But the key is to get the right height you need now. I am always looking at other stuff to see what might be just the ticket.

You might want to look at the following as a diffrent mounting source since you have a Monolithic Rail.

CLICK ON THE PIC


CLICK ON THE PIC


But if you go with a LaRue mount, you get to place that optic on diffrent uppers, or if things change and that upper gots to go. You still have a optic and mount to use on other rifles.

Just some thoughts.

John
Both look like good options. However, I may at some point want to swap out my scope for a different optic, such as an Aimpoint or ACOG, but still want to keep the scope for my longer range antics. That being said, and have been using and feel comfortable with the Larue mounts, I think I'll be going that route. Most likely the new Accupoint will be held up by a SPR... Now just to get the mils down... 300yd zero, ya say? Now where is that calculator??!!
 
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