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5/17/2015 11:37:33 PM EDT
I have a AR-15 9mm rifle, that I had the barrel threaded.

My smith cut it 0.5 inches long - whereas the 9mm pistol barrels I've bought from Lone Wolf are 0.4 inches long, which I belive is the standard length for a 1/2" x 28 TPI 9mm thread.

So, my cans don't shoulder out on the barrel, but on the piston.

1. Any issues with this, or should I just have the barrel shortened down a bit to the normal 0.4 inch length of thread?
2. Any reason for the 0.5 inch length, or did he just not do it correctly?

I also had him thread a .578" x 28 TPI barrel, which I've not yet measured.  What is the standard thread length for that size?

Thanks,
5/18/2015 10:02:53 AM EDT
[#1]
Quoted:
I have a AR-15 9mm rifle, that I had the barrel threaded.

My smith cut it 0.5 inches long - whereas the 9mm pistol barrels I've bought from Lone Wolf are 0.4 inches long, which I belive is the standard length for a 1/2" x 28 TPI 9mm thread.

So, my cans don't shoulder out on the barrel, but on the piston.

1. Any issues with this, or should I just have the barrel shortened down a bit to the normal 0.4 inch length of thread?
2. Any reason for the 0.5 inch length, or did he just not do it correctly?

I also had him thread a .578" x 28 TPI barrel, which I've not yet measured.  What is the standard thread length for that size?

Thanks,
View Quote


All the answers you seek are here: Thread Guide
5/18/2015 10:28:06 AM EDT
[#2]
Silencerco also has their own set of published thread specs - you can find it in the support section of their website.

If you're going to be using a piston with a spacer, then you'll need the threads to be around 0.4" (the exact number is on their print)

I believe the Octane fixed mounts will accept longer threads and still allow the mount seat on the shoulder of the barrel - but you will have exposed threads inside the blast chamber of the suppressor.

5/18/2015 10:49:12 AM EDT
[#3]
there is no real standard. Different suppressors and different mounts have different requirements. You should have specified to the smith the specs that your particular can and mount need.
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