DPMS LR308 AP4 Cheek Weld ?

[outdare]

Hello All,

I have a 308 AP4 set up with Burris TAC x-high rings with a Bushnell scope. I am having issues with eye to scope alignment. With the setup I have I am dancing my head around to find the sweet spot on the scope. I was hoping I could get some suggestions on how I can fix this. At this point with my large melon I am having to push my head down into the stock to get the correct alignment.

[survivalshop]

I use the same rings on my 20" ,but with an A2 stock . They are about as high as you can get, but there my be others out there higher .

They make extensions rail mounts , but that would put you too high & have to go to a lower ring. I do not like the rail extensions ,but use one till I get the rings /mount that works .

Rings & one piece mounts are some times measured differently from the manufacturers , some measure from the bottom of the scope cradle of the ring , some measure from the dead center of the scope, to the rail flat.

Check Larue to see if they have some thing that's a little higher than what the Burris rings are . I think Burris measures from the bottom of the ring to the rail flat.

When I get time I will measure my one piece Burris mount & see what it is .

[Robocop1051]

The Magpul MOE and CTR stocks both accept cheek risers. They come in 2 or 3 different heights. They also accept the Magpul enhanced butt pad. That makes for a much more comfortably shoot.

[outdare]

Thanks for the replies. I'll check out Larue's webpage and see what they offer.

I have the original stock on the gun now. I am not sure if a riser is what I am looking for. If I installed a MOE/PRS style of stock would I have to replace the carbine buffer tube or buffer?

Thanks,

Bill

[edgecrusher]

for a moe carbine stock swap no, for the prs or moe rifle stock you will need to change to a rifle tube, rifle buffer, and spring

[Jgun]

Just to add my two cents to the responses that you've already gotten. If I understand your original post, it sounds as though your saying that with your present stock and high rings your finding that the scope is still too low for your taste, because you state that you have to "push your head down to line up". From that statement it sounds as though your not going to benefit from a stock riser, which would locate your head higher in relation to the optic. It would sound as though your best option may indeed be to use a rail riser to raise your rings and scope as a unit, as stated by survivalshop. I don't know how much higher you think you need to raise the optic, but I've seen risers from YHM and Larue (and others)that will raise your optic  .250-.500" and even one that raises it .750", but I've got to say, your setup looks pretty tall already. Unless your a really big guy (with head to match), maybe it's a matter of practice to find and repeat the proper cheek weld. You also state that  your forced to move your head around in order to find the optic, which sounds more like the scope is too high and you don't have any cheek weld, (which is what I'd find if I mounted a scope using those high rings you've got on there. In that case the Magpul cheek risers would be the solution (or lower rings). Which is it , scope too high, or scope too low, presently?

[outdare]

I am a big guy at 6'3 with a large head. (7 5/8" hat size) I am finding the scope to low. I have to jam my check into the stock to get the correct alignment. I looked at the Larue mounts and they are nice, but they are pricey.  The thing is that I have other rifles with not one issues like this and using normal rings. Such as a Rem 700 25-06 with standard low rings and the cheek weld is perfect.

Thanks for the replies.

[Jgun]

Correct me if I'm wrong, but doesn't the design of the bolt gun stock, angle the stock down behind the barrel? If thats the case, Your going to have to try to find taller rings or go with the riser, because the buffer design of the AR means that You can't get that any lower with the AR operating system. Good luck with it, and you should share your solution with the forum. Maybe you'll be able to save some other member from having to go through a lot of trial and error.

[BayouBob]

Two inexpensive options to get your scope where you need it are the mini-picatinny risers you can get from several sources including flea-bay for about $15 each or the Millett extra high angle lock rings for about $40.  I use the Milletts on my 450 Bushmaster and they are just right and very strong.

[survivalshop]

He already has Burris extra high rings & they are about as high as you can get. I have the same type of problems with my cheek weld also . I have to go extra high in all my AR's I put scopes on.

The rail extensin is the way to go , you just have to figure the measurement of what more is needed.

You can do that by taking the ring tops off & with the rifle supported so you can get behind it & sight through it , just add some shims under the scope to get it where you can get a good sighting & add up the amount of shims you put under the rings ( front & back should be the same ) , that will get yo the added amount you will need .

You will have to look up in the Burris web sight on where they measure there ring height & your added measurement of shims gives you a total scope height & you will have to mix & match ring height & a riser height to get the measurement close to what you need .

You can use any thing for shims , just so you get a good measurement. Looks like the X Tactical , extra high are 1" from flat top to bottom of ring .

[outdare]

Thanks for the suggestions. It didn't even occur to me that I could shim the mounts for a little extra height. I also have a 3/4" riser and some Leopold low rings around here as well. That might be an option. I just don't like to use the risers if I can get away with it. So far I have ordered a new stock. (I dislike the stock one and feel it is do with an upgrade regardless.) I bought a Vltor IMOD basic based on the reviews it received. I chose this one because I already have a Magpul MOE on another rifle and can swap it over if I want o try it out. I also ordered a heavy buffer/spring from Slash's heavy buffers. I add this because of the great customer service I received. It really has nothing to do with cheek weld. Clint responded to my emails quickly. So I give him a big thumbs up for customer service.

[edgecrusher]

you'll enjoy clint's products as much as his service  <thumbsup>

[outdare]

I received the VLTOR IMOD stock yesterday and installed it today. I am really impressed. I did not expect the improvement I received.  <thumbsup> The design of the VLTOR lends itself to a better cheek weld. I verified this offhand standing and was able to fall into a correct cheek weld. (insane) I am attributing this to the angled pieces on the side of the stock. Honestly if I had know I would have done this along time ago. Here are some pictures. I am not sure if you can tell the difference between the stock in the photos or not.

[img width=810 height=456]http://i1075.photobucket.com/albums/w421/outdare/Vltorstock.jpg

[Jgun]

If I'm understanding you correctly, are you saying that your original problem was not one of the scope being to low, but of your not being able to find a repeatable/comfortable spot to rest your cheek on the other butt stock? the Vltor isn't actually any lower than the original, are you saying that the angled flat surface on the Vltor stock is allowing you to raise the gun higher in relation to your cheek than the other one did?

[outdare]

Honestly I don't know what I am saying. I tried this off hand in the bedroom and had good results. I have yet to take it to the range to put rounds through it. My initial response was a marked improvement in cheek weld over the original stock. My guess is that the butt plate is a little longer (I will measure later today) than the original stock allowing me to place the gun higher on my shoulder thus resulting in a more comfortable position. This with the angled side allow for a quicker repeatable cheek weld. I am not sure if I can be more descriptive until I shoot the gun. So I guess yes would be my answer.  8)  I measured the stocks and there is no real noticeable difference in size. The VLTOR is 1/8" longer from front to back and they are the same in the length of the butt pad at 5". The VLTOR has more of an angle at the bottom than the DPMS stock. 

[survivalshop]

It sounds like the stock fits your type of cheek weld better ( or your face structure ) This is not always the case ,but not unheard of .

[Jgun]

It's funny, this is kind of like trying to diagnose a car problem when someone is describing it over the phone. I had originally been under the impression that your problem was that when you shouldered the gun comfortably with your cheek resting on the stock,the distance between the top of the stock and your eye was more than the distance from the stock to the center of the optic, what I'm getting now, is that you've been unable to actually shoulder the gun comfortably because you couldn't rest the stock against your shoulder while resting your cheek against the top of the stock without lowering your head.

Not that I'm one to be giving advice, but I've been told by many people, that you shouldn't have to strain your neck to get down to the stock, you should bring the stock up to your cheek, that way you'll be more comfortable, and should be faster and more accurate when shooting off hand, so it sounds like your on the right track, I guess I wasn't hearing what you thought you were saying.

[outdare]

For me it is hard to explain what the issue was other than I had to press my cheek into the stock to get the proper weld. I think the VLTOR stock with its angled side allows my cheek a little more room and aids in the alignment. So it does lower my cheek down just a little. It is a hard to measure the difference of cheek height, but again I have not shot the weapon. I will report back when I do.

[antifederalist22]

I tend to have either a LaRue SPR, American Defense Mfg Recon, or Bobro optic mount on all my AR platforms--each of them being a mount that throws forward the optic and that gives me more area to get the eye relief just right.  These mounts also have optimal height (placing the centerline of the optic about 1.5" -1.9" above the rail).  Do not go too low on the ring height or you will be placing your cheekbone along side your stock rather than resting on top of it.  These are all QD mounts, so removing them to adjust for eye relief only requires hands, not tools.

http://www.laruetactical.com/riflescope-mounts

http://www.bobroengineering.com/browse/category/scopemounts/

http://www.americandefensemanufacturing.com/browse/category/opticmounts/scopemounts/

[unforgiven]

All great mounts for sure. <thumbsup>