Gunsmithing Length of pull for prone.

[goodgorilla]

I have not yet measured my length of pull, but after reading some, I plan to do it like this: Take your rifle, measure the distance from the trigger to the end of the butt to find the length of pull on the rifle. Then compare that number to the length of pull it is recorded to be, to check if you did it right. Next you take your rifle in your shooting arm, place the butt of the gun is resting against your bicep, then with your fore arm facing towards the ceiling you measure the distance from the trigger to your trigger finger. You add the distance from the space between your trigger finger to the trigger, to the length of pull of the gun you measured earlier. That will be your actual length of pull.

I've read in a few locations that when you go prone, your length of pull is increased by 1/2 an inch. Ultimately I would like to shoot prone all the time, but I know I will be doing bench rest shooting until I can get down the basics. Anyhow, what is your experiences with length of pull and the prone position? Do you think the way I plan to measure length of pull is good?

 

[mcfred]

I've read in a few locations that when you go prone, your length of pull is increased by 1/2 an inch.

I'm not an expert but I tend to prefer a shorter LOP for prone. I know Kregoff has an elaborate procedure for fitting a shotgun stock, but I would be inclined to experiment with dimensions on my own to see gives the most comfortable and repeatable natural point of aim. Obviously an adjustable stock makes this a lot easier.

 

[George63]

long enough that the bolt does not hit your face - any thing else is just preference

 

[steve123]

I like my LOP longer for prone off the bipod so the butt of the stock is pressed against the shoulder somewhat firmly with the rearward tension from loading of the bipod.

Having a adjustable LOP and cheek piece really helps me get comfortable behind the rifle. My go-to bolt rifle uses AR-15 rear stocks and has a magpul PRS on it that can be adjusted right then for both LOP and CH without tools.

 

[goodgorilla]

I am going to get an 3 way adjustable butt plate put on. But I'm not 100% about what to get the standard length of pull at. The adjustable butt plate give a variance of 1 inch, I think I will experiment a little with some tape measure.

 

[Lowlight]

You measure from the inside crook of the arm (elbow) to your finger on the trigger, not a straight trigger finger but actually engaging the trigger.

If you are just shooting prone you can add a 1/2" to that, however if you are gonna shoot positional, or bench you would subtract about 1/4 to 1/2" off the measurement.

If you have an adjustable, you can measure it, add in the 1/2" then remove 1" when on the bench.

 

[goodgorilla]

You measure from the inside crook of the arm (elbow) to your finger on the trigger, not a straight trigger finger but actually engaging the trigger.

If you are just shooting prone you can add a 1/2" to that, however if you are gonna shoot positional, or bench you would subtract about 1/4 to 1/2" off the measurement.

If you have an adjustable, you can measure it, add in the 1/2" then remove 1" when on the bench.

So, I will need to find my standard length of pull and subtract a half inch. When doing prone shooting I will increase the adjustment by an inch. Just for some extra info, I will be using a bipod, if that needs to be factored in.

You say add in a half inch? Wouldn't it be subtract because you said take off a half when shooting bench? I imagine the adjustable butt plate starts at the compact position and would get extended 1 inch for prone. Then again, if you add in a half inch, than subtract 1, that would equal subtracting 1/2 inch from the start.

 

[downlow]

I've read in a few locations that when you go prone, your length of pull is increased by 1/2 an inch.

That's what I've found. All my hunting rifles are 13-1/2" LOP. When I started shooting F-Class, and LR shooting, prone off a bipod, I needed 14" LOP.

 

[goodgorilla]

I measured my length of pull this morning, I did it similar to the way I described, although when I measured the extra distance I did it a little different. I positioned my arm and hand in firing position, then I used a pen to draw a line on my forearm where the butt of the gun ends. Then I measured the distance from the line to the crease on my arm where the forearm ends. Then I added that to the measured lop of the gun which I measured to be 13.5 but the factory labeled it as 13.375 or something like that. I used the measured distance of 13.5 with the distance on my forearm (inch and a half) to get the sum of 15. Now I subtract 1/2 of that to get 14.5 for the adjustable stock. I wonder if 15 lop is unusual for a 6'3" guy like myself, I would imagine it is normal.