Just curious ... what is the measurement of on the LOP for your long arm?

 

Do you feel that too close render the BUIS useless because the rear apeture ring is just a big blur?

The rear aperature ring should be a blur. The front sight is what should be in focus.

 

The LOP really depends on what you feel comfortable with. Do you shoot bladed style (body turned slightly to the right or left (depending on what side you shoot from), or do you shoot squared-off? If you shoot bladed style, you may want a longer LOP. If you shoot squared off (like I do), you may want a shorter LOP so it's more comfortable.

My rule of thumb is that I want the tip of my nose on the charging handle. That translates to one of the middle positions (3 I think) on a standard adjustable stock.

Average normal sizes are:

14" Adult Male

13" Adult Female

12" Youth

11" Child

Currently, it's on position 2 with 11" LOP with the Magpul MOE.

 

I'm so up front that the apeture ring is none existance, so there is not sense of alignment.... not sure if that makes sense. My nose isn't touching the charging handle but it's about 1 - 1.5" away.

 

Krdshrk - What position is your stock? If you don't mind me asking.

 

I'm taking it down to Arms-n-Ammo this weekend to get it adjusted, hopefully to position 4, which should be 12.5" LOP.

Mine's in position 3, I believe.

Based on the picture and measurement of what I have. You seems to have an LOP of ~12" including the pad, but your rear sight might be an inch or so more forward than my setup.

 

Not sure if this is correct, but I was taught the front sight should be as far as possible and the rear sight should be as rear as possible.

 

The additional 1.5 to 2 inches will definately help with "disappearing" of the rear apeature from the "sight picture". Maybe I'll move the rear sight instead of re-pin of the stock.

Im 6'5 and mine is in the 3rd position out. LOP on mine is 12" withough the pad (I took it off), my rear sight is as far back as possible and have no problems with it. btw I shoot squared up and NTCH

 

Im 6'5 and mine is in the 3rd position out. LOP on mine is 12" withough the pad (I took it off), my rear sight is as far back as possible and have no problems with it. btw I shoot squared up and NTCH

 

 

Nick,

 

Question, so if you move just 1 inch closer to the sight. Do you have the problem that I've described?

Yes and no, the rear aperture does blur out but I can still see a outline of it no problem when shooting NTCH. I just put my face almost touching the rear sight and could still make out the outline of the aperture.

Dammit ... it must be these Chinese eye I have then!!! ... LOL

Dammit ... it must be these Chinese eye I have then!!! ... LOL

 

I'm chinese too.... and have horrible vision...

Haha, I put the red dot on mine and its a huge improvement over trying to use the irons. I wear glasses and my vision sucks so with the dot its alot easier and faster to get on target

LMAO ...

 

It's been a while since I've shot an AR, I think I can manage but I'm trying to teach my wife how to handle the AR and I want it to be as easy as possible.

 

I will be getting an EoTech XPS3-2 in the near future, but that's after she learns how to use the BUIS, but until then I need her to learn to shoot without optics.

 

Man... first day on the forum and I'm not getting any work done.

8500 posts (well, close to), and I still never get stuff done

 

And yes - learning how to shoot with irons first is important!

You can measure your appropriate length of pull by bending your elbow at a 90* angle, and measuring from the inside crease of your elbow to the last knuckle on your pointer finger. This will get you a very good idea of where you should be. You may want to alter it some based on what you're shooting. If you're using irons, the measurement should be pretty accurate. If you're shooting with a red dot or reflex sight and want a shorter rifle, you can shorten the length of pull because it won't effect your aiming. If you're shooting off a bench with a magnified scope, you may want to elongate the LOP.

 

Yeah.... that's pretty much what I did to measure my wife's LOP. It's 12.5", but I didn't know what position on the stock would be equilivent to 12.5. The dealer told me, most people get it at position 2, which equates to 11" .... so that's where I am now..

If I remember correctly, it should match the length between the trigger and the end of the stock. It was easier for me to do because I built my own AR, and I built the lower and pinned the stock before even owning an upper, so I never constructively owned a complete AR until it was all legal. It's a little trickier when you already own an AR, or if you're purchasing one new.

I hear ya... I didn't have the luxury of "trying it on for size" prior to placing the order with an out of state FFL.

 

I've also searched all over the web for stock pin position in relation to LOP. But the "pin stock" rule only apply to a few states so the information was none existance or I couldn't find it.

Saw this on Magpuls site dont know if it helps or not but heres some measurments I found for their MOE stock

• LOP Adjustment Range: 3.25 in.
  
• LOP, M4 Collapsed: 10.70 in.
  
• LOP, M4 Extended: 13.95 in.
  

Saw this on Magpuls site dont know if it helps or not but heres some measurments I found for their MOE stock

• LOP Adjustment Range: 3.25 in.
  
• LOP, M4 Collapsed: 10.70 in.
  
• LOP, M4 Extended: 13.95 in.
  

 

That's at the Min/Max positions (all the way in or out).

That's at the Min/Max positions (all the way in or out).

 

Gee thanks I realize that, and if you take the adjustment range you can approximate how long the LOP will be, if my math is right each notch out should be approx .65"

 

So if all the way collapsed = pos 1 and fully extended = pos 6

pos 1 = 10.70" lop

pos 2 = 11.35" lop

pos 3 = 12.00" lop

pos 4 = 12.65" lop

pos 5 = 13.30" lop

pos 6 = 13.95" lop

 

Edit: Those numbers are using the measurements for a Magpul MOE stock, so if you use a different stock the LOP may be different as well, but they should be close.

Edited July 6, 201214 yr by alowerlevel

Gee thanks I realize that, and if you take the adjustment range you can approximate how long the LOP will be, if my math is right each notch out should be approx .65"

 

So if all the way collapsed = pos 1 and fully extended = pos 6

pos 1 = 10.70" lop

pos 2 = 11.35" lop

pos 3 = 12.00" lop

pos 4 = 12.65" lop

pos 5 = 13.30" lop

pos 6 = 13.95" lop

 

Pfft math. You must think I'm asian or something.... oh wait.......

Pfft math. You must think I'm asian or something.... oh wait.......

lol, c'mon you should have been able to do that math in your head then , I had to use a calculator and a pen and paper to make sure my math was right :mail:

I got 11" on position 2... so off by a bit .... but not much... ... I actually did the math on it too on a spreadsheet, but was off for some reason.... being I'm Chinese... I should have used my head instead of trusting the spreadsheet.... LOL

 

So we did some more measuring and because I'm 5'10 ... my nose is actually touching the charging handle with blade stance but about 2" away with squared stance. My wife is about 3" away with blade stance, so it was fine.

 

We stopped by Arms-n-Ammo this weekend, looking to pickup an M&P9 for my wife and Paul was nice enough to take a look at the AR. He saw the same problem I was describing with the rear sight. I tried one of the AR he had with the Magpul sight and it didn't have that problem.

 

NJPilot guest us in CJRPC on Sunday and we tried the AR for the first time. She is able to get about 6" group with BUIS at 50 yds for the first time handling an AR or any long arm, so it works.... LOL ... no need to repin the stock!!! ... I was so dreading the repin.