Gunsmithing Barrel Nut Wrench Size - 308

[cfulback32]

I was assembling my upper tonight (first time I have assembled an upper) for my 6.5 Creedmoor Mega Maten build and ran into a problem with the barrel nut. It seems like the barrel nut wrench is too large for the barrel nut. When I try to torque down the barrel nut the wrench slips around the teeth of the barrel nut. I was expecting all 4 points on the wrench to evenly engage, but it seems like the wrench is too big. Anyone have any advice? Again, first time I have assembled an upper.

Components in the picture are:
Krieger 6.5CM barrel
Mega Maten Upper
DPMS 308 Barrel nut from Rainier
PRI 308 Barrel Nut Wrench for DPMS / KAC pattern

 

[cfulback32]

Re: Barrel Nut Wrench Size - 308

I forgot to add that both sides of the wrench have the same issue.

Since the barrel nut threaded on ok, I assume that it is not the wrong size barrel nut. I guess the wrench could be the wrong size? That seems pretty unexpected since it is labeled DPMS / KAC.

 

[2156SMK]

Re: Barrel Nut Wrench Size - 308

You need to use an AR-15 wrench with that barrel nut.
The PRI wrench you have is for freefloat barrel nuts where the gas tube passes through the nut, not over it like an AR-15...

 

[Stewart]

Re: Barrel Nut Wrench Size - 308

Looks like you need a standard ar-15 barrel nut wrench not an ar-10 wrench.

 

[cfulback32]

Re: Barrel Nut Wrench Size - 308

Thanks guys, didn't realize the standard DPMS 308 barrel nut used the AR 15 sized wrench. I just ordered one and will give that a shot.

 

[stangfish]

Re: Barrel Nut Wrench Size - 308

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Stewart</div><div class="ubbcode-body">Looks like you need a standard ar-15 barrel nut wrench not an ar-10 wrench.
</div></div>

This ^

 

[bronco_buster]

Re: Barrel Nut Wrench Size - 308

Food for thought...

1) The PRI tools are THE SHIT! Best wrenches period.

2) The AR10 wrench won't work with your nut

<span style="color: #FF0000">3) The AR15 tool won't work with your barrel either!!</span>

I had the exact same problem with my Mega/Troy TRX combo. I bought the AR10 wrench...Midway sent me the AR15 wrench. Its designed for a non-bull barrel AR15 and obviously didn't fit over the barrel. Then they sent the AR10 wrench. Its too big, just like your problem. Then I bought the AR15 "bull barrel" wrench. Again, <span style="font-weight: bold">it doesn't work!!!!</span> The hole is for the smaller tenon of the 223 platform and won't slide over the 308. So what I did was take the bull barrel AR15 tool and spent 2 hours grinding and opening the center hole to accommodate the AR10...I need a lathe. Its still a great tool, and PRI makes great products, but they have no off the shelf solution for the Mega owner who has to use an AR15 barrel nut pattern. Hope this helps.

Pics of the tool that I bored out to fit the AR10: