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frozentundra
06-13-2018, 11:05 AM
Is there a good way to mount a low power variable scope at approximately 1.25" to centerline on an AR? Or even very slightly less?

Most of the one piece mounts are 1.5" or higher, and I find that to be too tall for an optimal cheek weld, personally. It is even worse for my young daughter. She only gets a marginal jawline weld. I can see the utility if you are trying to go over the top of BUIS, have a giant 50mm objective lens, or have a relatively large/thick head/face. Using traditional rings seems like it would push the optic back to the rear quite a bit?

I'm thinking about a simple, lightweight BCM ELW-F upper with nothing else mounted on it. Just a lightweight LPV optic that's mounted lower to optimise cheek weld. And a sling.

Are there any good, lightweight options for doing this?

texasaggie2005
06-13-2018, 12:14 PM
If you want a unimount, Nightforce (http://nightforceoptics.com/accessories/ultralite-unimount) has one at 1.125"; $252 at Primary Arms (http://www.primaryarms.com/nightforce-uni-mount-1-125-inch-high-1-piece-20moa-mount-30mm-a190).

Clusterfrack
06-13-2018, 12:15 PM
I wouldn’t go lower than Full Co-Witness. That’s a very versatile scope height that works standing, prone, and awkward positions too.

BTW, that BCM ELW fluted is my favorite upper.

Toonces
06-13-2018, 12:17 PM
Your desired height is kinda in no man's land. But, if traditional style rings work for scope positioning, some of the see through scope rings are your requested height.
https://www.midwayusa.com/product/1477171910/weaver-1-see-thru-weaver-style-rings

These are a little lower.
https://www.midwayusa.com/product/2330133960/ironsighter-1-weaver-style-rings-with-one-extended-ring

https://www.midwayusa.com/product/1477123043/weaver-tactical-picatinny-style-rings-matte

These one piece mounts are lower than 1.5", but slightly over the 1.25" requested height. However, the ADM has extension for ease of scope positioning.
https://www.midwayusa.com/product/1018513433/nikon-black-precision-1-piece-scope-mount-picatinny-style-with-integral-30mm-rings

https://www.midwayusa.com/product/2626483310/american-defense-recon-quick-release-extended-scope-mount-picatinny-style-with-rings-ar-15-flat-top-matte

critter
06-13-2018, 12:24 PM
Perhaps another option to consider... LaRue Tactical makes a cheek riser that is spring loaded (moves back) so that it doesn't block the charging handle. I know it attaches to the CTR stock. Perhaps others as well. Raising the cheek combined with co-witness height may work for her as she grows into the standard weapon configuration.

ETA: since it doesn't block the charging handle, any height padding could be rigged on for a perfect fit.

ETA 2: Correction of an error, not Magpull - it's LaRue Tactical who makes it.

It's called the R.I.S.R. model LT748-BLK is the black one.

frozentundra
06-13-2018, 02:19 PM
I just broke out the calipers and figured out that the SWFA mount I've been using is sitting 1.5925" from top of the rail to center of scope. That's higher than I thought.

My Troy fixed front sight sits at 1.375" (off the BCM KMR rail to the tip of the post as it came set up from the retailer). That is the better part of 1/4" right there.

The Niteforce Ultralight Unimount that texasaggie2005 linked above also comes in a 1.375" and 5.2oz. They also make a 'Unimount SR', which stands for service rifle, that is 1.35" to center and 5.2 oz. It has a more dramatic cantilever and was designed for being able to accomodate 'nose to charging handle' head position.

I had to call up customer service at Niteforece to find the weight, as I couldn't find it listed anywhere online. They had to request the information from engineering and call me back. In speaking about the issue with the Rep (who was EXTREMELY helpful and prompt, by the way), I found out that, many years ago, they used to do special runs of mounts for the Military that were specifically specced out to 1.265". He said he thought some of them went to the SEALs, or some such. Pretty interesting, and it really mirrors my ideas about what would be optimal height for a scope on an AR.

Does anybody know if there is a standard specification for the tip of the front sight over the plane of the flat top receiver? I'd be curious to know this.

frozentundra
06-13-2018, 02:29 PM
Perhaps another option to consider... LaRue Tactical makes a cheek riser that is spring loaded (moves back) so that it doesn't block the charging handle. I know it attaches to the CTR stock. Perhaps others as well. Raising the cheek combined with co-witness height may work for her as she grows into the standard weapon configuration.

ETA: since it doesn't block the charging handle, any height padding could be rigged on for a perfect fit.

ETA 2: Correction of an error, not Magpull - it's LaRue Tactical who makes it.

It's called the R.I.S.R. model LT748-BLK is the black one.

This product's existence goes to show that quite a few people feel the same as I do about their cheek weld on the AR platform.

It just seems crazy to me to add all that weight when you could accomplish the exact same thing by simply making the mount a tiny bit lower (thus fractionally lighter). And without worrying about potentially mucking up the charging handle operation.

texasaggie2005
06-13-2018, 02:30 PM
... Does anybody know if there is a standard specification for the tip of the front sight over the plane of the flat top receiver? I'd be curious to know this.

1.41" above flattop, I believe.

Wayne Dobbs
06-13-2018, 04:23 PM
1.41" above flattop, I believe.

The PLATFORM where the flat top AR front sight is mounted is supposed to be 1.98 inches above the top surface of the barrel. Where the tip of the front sight is will depend on what detent click it's set on in its channel.

texasaggie2005
06-13-2018, 04:35 PM
The PLATFORM where the flat top AR front sight is mounted is supposed to be 1.98 inches above the top surface of the barrel. Where the tip of the front sight is will depend on what detent click it's set on in its channel.

Forgive my ignorance, but wouldn't the barrel's profile (HBAR, med-con, LW, etc) affect the 1.98"?

GJM
06-13-2018, 04:36 PM
From a pure technical shooting perspective, the lower and further inboard you can get the butt of the carbine, the better the recoil control. A taller mount allows you to get the butt lower and still have a decent head position.

Wayne Dobbs
06-13-2018, 05:11 PM
Forgive my ignorance, but wouldn't the barrel's profile (HBAR, med-con, LW, etc) affect the 1.98"?

It's an M4 standard, so I guess that's possible.

frozentundra
06-13-2018, 11:23 PM
From a pure technical shooting perspective, the lower and further inboard you can get the butt of the carbine, the better the recoil control. A taller mount allows you to get the butt lower and still have a decent head position.

Do you think that a roughly 1/4 inch difference in scope height makes a big difference in that regard? Serious question. I'm certainly not very knowledgeable about running ARs at a high level, and am always eager to learn something new from somebody who is.

I just can't imagine that a small for age 11 year old girl (my daughter) should optimally use the same comb height as a smaller than average guy with a thin face(me) who should also optimally use the same comb height that works best for the largest gorilla humans who use rifles anywhere on the planet. It can definitely be accomodated, and I'm sure there are trade offs, but I have a gut feeling that it's passing the point of diminishing returns. People have such different size/shape heads/faces. To me it seems like putting large backstraps on a Glock 21 and giving it to a kid.

But I've been know to be wrong before. Alot.

Edit to add: I'm probably using the term comb height incorrectly here. I mean distance from the top of the stock to the center of the optic. Adjusting the optic lower wouldn't change comb height, I guess. It's weird on an AR.

GJM
06-14-2018, 06:29 AM
Do you think that a roughly 1/4 inch difference in scope height makes a big difference in that regard? Serious question. I'm certainly not very knowledgeable about running ARs at a high level, and am always eager to learn something new from somebody who is.

I just can't imagine that a small for age 11 year old girl (my daughter) should optimally use the same comb height as a smaller than average guy with a thin face(me) who should also optimally use the same comb height that works best for the largest gorilla humans who use rifles anywhere on the planet. It can definitely be accomodated, and I'm sure there are trade offs, but I have a gut feeling that it's passing the point of diminishing returns. People have such different size/shape heads/faces. To me it seems like putting large backstraps on a Glock 21 and giving it to a kid.

But I've been know to be wrong before. Alot.

Edit to add: I'm probably using the term comb height incorrectly here. I mean distance from the top of the stock to the center of the optic. Adjusting the optic lower wouldn't change comb height, I guess. It's weird on an AR.

As described by Brian Nelson, lead instructor at TPC’s Carbine Mastery class, controlling the carbine is, in this order, stance, grip, the muzzle device, then operating components. The smaller you are, the more important leverage and aligning the skeleton becomes, so I would say getting the butt lower and inboard is especially important for her. What I don’t know is what optic she is using, and how that works for her. Probably less important with an Aimpoint and more important with a LPV.

frozentundra
06-14-2018, 10:39 AM
As described by Brian Nelson, lead instructor at TPC’s Carbine Mastery class, controlling the carbine is, in this order, stance, grip, the muzzle device, then operating components. The smaller you are, the more important leverage and aligning the skeleton becomes, so I would say getting the butt lower and inboard is especially important for her. What I don’t know is what optic she is using, and how that works for her. Probably less important with an Aimpoint and more important with a LPV.

Interesting way to codify that. Makes sense.

This would be a LPV. The main application would be learning positional rifle shooting techniques and practical rifle marksmanship out to 300 yds.

I must say, I'm a little confused about the relationship between what I perceive as modern 'gunfighting' centric carbine technique--which seem optimised for putting volume of fire on target, really FAST, at close to intermediate range-- and traditional positional marksmanship technique, such as might be taught at an Appleseed event, focusing primarily on precision at range. Or perhaps by Randy Cain or Gunsite as practical rifle courses. I wonder where/how the utility of one begins and the other ends? Or is there more of a hybridization that I don't understand the nuances of going on?

I wish I had the resources and ability to travel around and take a bunch of serious rifle training, but I've prioritized pistol training to the relative exclusion of rifle training.

KneeShot
06-14-2018, 11:20 AM
Frozen tundra,

What positions are you teaching your daughter to shoot from? There have been some recommendations on this thread, the Larue risr looks like a tool that could add value. Here are my lessons learned teaching kids to shoot. I have 3, current ages 10, 7 & 6. I'm a military dude, been through some great training including TPC Carbine w/ Brian Nelson that George references above.

Lessons - started my oldest when he was 6 on an AR w/ a .22LR conversion kit and an older EOTECH. He still needed a "chin weld" even w/ the stock collapsed. Position standing or sitting, rested on bags.

Age 8 a family friend gifted him a well used .22LR semi auto Savage (62?), full sized Rifle. Though he grew he still used a chin weld, rifle rested while standing. Struggling for body position.

Age 9-10 Santa brought him a fixed 4x Leupold for his Semi auto Savage. Standing, rifle rested, chin weld he makes consistent hits on 2" steel at 45yds. With the Fullsize rifle he still struggles to shoot standing/freestyle.

Observation - The gun he has the most fun shooting is his little brothers Savage single Shot "Rascal". He can shoot it from any position and it fits (fits all of the kids).

If I could do it over again - I would start w/ a savage rascal w/ a good fiber optic front sight.

Note - I think red dots or fiber optics make it a lot easier to teach younger kids. Sight alignment and sight picture can be a struggle w/ iron sights.

The Savage rascal costs 150 - 200$ depending on stock material. Some of the scope mounts to fight for 1/4" can cost that much.

Just my .02 cents.

Jeremy

4gallonbucket
06-14-2018, 12:21 PM
I must say, I'm a little confused about the relationship between what I perceive as modern 'gunfighting' centric carbine technique--which seem optimised for putting volume of fire on target, really FAST, at close to intermediate range-- and traditional positional marksmanship technique, such as might be taught at an Appleseed event, focusing primarily on precision at range. Or perhaps by Randy Cain or Gunsite as practical rifle courses. I wonder where/how the utility of one begins and the other ends? Or is there more of a hybridization that I don't understand the nuances of going on?

This is a great question. I've been through Appleseed as well and I'm interested in opinions on how the traditional positional shooting taught there works with modern carbine technique. Subbed to hear thoughts on this one.

Clusterfrack
06-14-2018, 12:39 PM
I took my 13 year old daughter to Appleseed, and it was a great experience for her. She shot a Sharpshooter score with a 10/22 and a 4x scope. The fundamentals she learned were excellent, but in my opinion, limiting and not in line with modern rifle and carbine technique.

At the time, I was competing heavily in precision tactical and carbine, and found it pretty easy to shoot Expert (Rifleman) with a bolt action .22. My technique (especially with the sling) was not in line with Appleseed dogma, but the head instructor finally told everyone "Leave him alone. He knows what he's doing." I almost won another Rifleman patch with an AR and a red dot.

A few thoughts:

Cheekweld: super important if you are shooting a rifle with a high-power scope. You need to be able to line your face up so you can see through the scope. I also use my cheek to stabilize a heavy precision bolt gun when standing and kneeling. However, your head position is usually different when shooting prone, and you need to set up your rifle to work in all positions. I've never found a cheek-riser system that worked well on an AR, and frankly it's just not that important unless you've got big glass.

Stock fit: super important, and much more so than cheek position. The stock needs to go in the pocket of your shoulder. Otherwise your POI will be inconsistent and followup shots will be slow.

My daughter learned to shoot a bolt gun with a cheek riser. She also learned to shoot an AR set up in a standard configuration. It wasn't a big deal.

https://uploads.tapatalk-cdn.com/20180614/19e7c98efb1a46a7c828ef77b63a9bc6.png


https://uploads.tapatalk-cdn.com/20180614/4d18674bba9343df47129dd8c960bf8e.png

Crews
06-17-2018, 06:16 AM
Badger has an excellent unimount, comes in some lower heights.


Sent from my iPhone using Tapatalk

NH Shooter
06-17-2018, 09:54 AM
I'm thinking about a simple, lightweight BCM ELW-F upper with nothing else mounted on it. Just a lightweight LPV optic that's mounted lower to optimise cheek weld. And a sling.

Mine is currently set up with just a set of DD irons. As an old High Power shooter, shooting targets with just irons is a lot of fun;

http://www.canonshooter.com/photos2/bcmcarbine-1.jpg


I really like light weight when it comes to an AR. My BCM rifle is set up with the 16" mid-length ELW BFH upper and on a bench with bags, can shoot bug near-MOA at 50 yards.

That said, there are significant advantages to using an optic. I have toyed with the idea of trying the following optic/mount combo which amazingly comes in under 10 ounces total;

Leupold FX-II 2.5x20mm Ultra-Light Rifle Scope (https://shop.opticsplanet.com/leupold-fx-ii-2-5x20mm-ultralight-rifle-scope.html?_iv_code=LU-RS-FX2-25x20-58450) - 6.5 ounces

Aero Precision Ultralight 30mm Scope Mount (https://www.opticsplanet.com/aero-precision-ultralight-30mm-scope-mount-spr.html) - 3.2 ounces