Is there a machine shop or AR parts outfit that does custom work? Looking for an 8"  XM177 style flash hider with 1/2x28 TPI threads.

I have searched and not found anything like it. You know those 5.5" flash hiders you can use to extend a 11.5" barrel to be greater than 16" and legal by having it pinned and welded?

I would like to have one made that is 8" long in order to be able to permanent affix it to an 8.5" barrel to make it legal.
Why do that you say? Well there are several reasons. One is to be able to convert a pistol into 16" barreled carbine permanently (legal to do that I understand) and many types of 9mm pistols for example simply do not have 16" barrels available, but have barrels available with 1/2x28 TPI threads that could accept such a flash hider to be permanently affixed.

Another use is to be able to permanently affix to a carbine that you plan to SBR on a form 1, so that you can use it legally while waiting for time you want to do it, or the paperwork, with the permanently affixed flash hider extending the length to a legal 16"  like the XM177 clones, except with a shorter actual barrel than 11.5". I don't like fake suppressors as they are bulky and generally heavier. Any ideas on who could make an 8" FH similar to the 5.5" FH that currently exists?




TL;DR Need to have an 8" version of the 5.5" flash hider made with standard 1/2x28 TPI threads. Anyone have any leads on who could do this? I might be willing to order a quantity if the price was reasonable.

Can't answer the 8" barrel deal, but if desiring an xm177e2 style, buy a pencil 16",  have it cut to 12.75", and use a 4.5" moderator,  Bushmaster, brick made, as well as a brick grenade ribg on gunbroker, etc.

There are guys on here who can chime in on the work you need done and can take care of it.


I have a 4 1/2" moderator that's coarse threaded that if anyone needs it, it could be sleeved and thread to 1/2 x 28 I'm sure.

Thanks, but that's not really what I am looking for. Looking for a FH to extend a shorter barrel. Some one suggested I post the request for info in the retro forum because of the custom nature of a lot of the retro build work.

I have a XM177E2 build, and love it!

I may buy a table top lathe and heavy duty drill press and see if I can manufacture a longer FH myself if I can't find anyone who can do it.

It's be a neat project, keep us posted and pics when you can.

You might be able to have someone make one, but frankly an 8 inch barrel with an 8 inch flash hider is going to look strange (IMHO)

I would sell the barrel and go with the previously mentioned plan - if you want that style FH.  Or go 14.7 inch barrel with A1 or A2 FH depending on preference.

I suggest retroarmsworks.com or maybe Brick would do it if you really want one made.

Thanks for the link!

Not exactly what you are looking for, but I do know there is a moderator that is threaded mid-way so it can be attached to a 16" barrel and look like it is one of the carbines with the moderator. I'd have to see if I bookmarked it back on my other computer.

As for what you are looking to do, I don't know of anyone who does custom work, but the machining itself should be pretty simple. The only thing I can think of is to ensure that it isn't made in a way that could reduce report like some of the originals did (if I remember correctly some of them had baffle-like structures. Not sure though!)

Good luck!

FYI: An 8" muzzle device on an 8.5" barrel will come out to about 15.8".


ETA: 15.875" +/-

How so?  8 + 8.5 = 16.5   If you account for a half inch of threaded area, should still hit 16".

If the FH was 8.5", with a half inch threaded area, that should make for 16.5" AOL.  ATF uses the dowel method from what I have heard, to determine barrel length.  That mean put a dowel down the barrel until it contacts the closed bolt, and put a tick mark at the point where it exits the barrel or permanent muzzle attachment.  Take the dowel out, and measure to the ticket mark. That must be at least 16".

Are you saying the threaded area is 0.7"?  if so a 8.5" FH should still be ok.

IIRC the threaded portion is .625 inches.

8 + 8.5 - .625 = 15.875

This would be correct. Typically, the threaded area is 5/8" (.625").

I am not sure I completely understand your logic. If you have an AR pistol now with the 8.5" barrel, why not go ahead and get a separate 16" upper to use for now while you are waiting to get the tax stamp for the lower? You can buy a complete 16" upper assembly for less than $300, throw a stock on the lower, swap the BCG and CH over to the new upper and utilize the weapon right away. When you get your tax stamp, just throw the 8.5" upper back on it, swap the BCG and CH back to the upper, and either keep the other upper or sell it. To me, this is the simplest and most efficient way of doing things.

Well what is less expensive, a permanently attached flash hider, or another complete upper?  Maybe $50 vs $500?

But also looking for a way to turn an RPB M10 semi auto pistol into a carbine, so the barrel would need to be 16" in order to be able to add a stock.  I think I have found some 8.5" barrels with 1/2x28 tpi thread for the M10, so a permanently attached 8.5" FH would be the ticket to do it legally.

If you don't want to go for style points put a thread protector on the threads and then find a piece of pipe with a .750" internal diameter and slider it over the barrel and tack weld in to place.  One of the sten kits has that where you just slide a piece of pipe over the barrel and weld it on so it's permanent and the legal length.