MK12 Mod 0 Accuracy

[Norseman1950]

I have a former military pre Mk12 Mod 0 Spr upper that I'm having some accuracy issues with. Shoots very good sub moa groups at 100M if I hold tight enough. The problem is it seems to fall apart at the 200M line. It went from sub moa @ 100m to about 2 moa at 200m. Mild winds that day... maybe 5mph or less. Seems to me it should do better than a 4inch group but in reality I'm not sure what I should expect accuracy wise. Load was 77smk... sd in the low teens. have no idea on the round count.

Thoughts?

 

[LoneWolfUSMC]

Re: MK12 Mod 0 Accuracy

Sub-MOA at 100 would lead me to believe it's not a rifle problem.

I would look at the load or the shooter.

 

[Norseman1950]

Re: MK12 Mod 0 Accuracy

It may very well be me... probably need to spend some more time with it. This precsion rifle thing isn't terribly forgiving of poor technique.

-D

 

[slothlacrosse]

Re: MK12 Mod 0 Accuracy

try a different load or a different shooter. i'll volunteer myself to shoot it until it works properly.

a friend of mine was getting good results with 69 gr FGMM. it might be worth a try.

 

[sobrbiker883]

Re: MK12 Mod 0 Accuracy

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">Sub-MOA at 100 would lead me to believe it's not a rifle problem.

I would look at the load or the shooter. </div></div>

Beat me to it.....

 

[VJJPunisher]

Re: MK12 Mod 0 Accuracy

think that upper is toast, sell it to me

 

[Norseman1950]

Re: MK12 Mod 0 Accuracy

I wouldn't want to burden you with this old worn out thing...

 

[TonyAngel]

Re: MK12 Mod 0 Accuracy

Norseman, I really don't know what you mean by holding the rifle tight enough. If you're bear hugging the rifle to keep it steady, all you're doing is inducing fatigue that is going to manifest itself in the form of shake. You only need to have a firm grip on the rifle, at most.

I also wouldn't put too much stock in your low sd readings. Most chrony's have about a 1% margin of error. Assuming a muzzle velocity of 2600fps, that's a 26fps margin of error for every recorded round. The only point I'm making is that you shouldn't dwell on it too much. I only use a chrony to get a good idea of my velocity, and let my groups show the accuracy potential of the load.

What load are you running in the rifle? What was your velocity? Right now, my knee jerk is to say that you just need more trigger time. I know that I had to work hard to shoot as AR as well as I can a bolt gun.