bringing the overall length up to about 15.5"??

Or is the barrel with flash hider 14.5?

I am trying to figure out how I can just get the overall length just a little over 16" for my build?

thanks!

I think you can get them either way. The shorter than 16 inch bbl has to have a permanent flash hider on it (ie, not removable) if its a regular rifle. Build it as a pistol it would be ok, but with no buttstock.

Last one I built, I opted for the 16" bbl plus a removable flash hider that made it like 17".  I wanted the removability and not have to worry about soldering/pinning it on.

I am sure the military probably has the shorter one with removable hider ...but hey, they got all the NFA type weapons anyway.

Quoted: Quoted: bringing the overall length up to about 15.5"?? Yes

OK so i could go with a 14.5 and then add a phantom flashhider to be legal?

Quoted: Quoted: Quoted: bringing the overall length up to about 15.5"?? Yes OK so i could go with a 14.5 and then add a phantom flashhider to be legal?

Yep, that's what I've got. Of course to be non-NFA the Phantom has to be permanently attached.

Quoted: Quoted: Quoted: bringing the overall length up to about 15.5"?? Yes OK so i could go with a 14.5 and then add a phantom flashhider to be legal?

Yes, but you have to solder it on to make sure it is not "easily removable"

Or spend the $200 and get what you want!

Yes. IIRC, the Phantom FS is 1 1/2" without the crush washer.
I played it safe on my build and had the barell cut to 14.25"


ATF opinion on permament mounting of FS...

"Dear Mr. :

This refers to your letter of March 31, 1998, in which you ask
about permanently attaching a muzzle device to various firearms.

A muzzle device, such as a muzzle brake or barrel extension, which
is attached to a barrel by means of welding or high temperature
silver solder having a melting point of at least 1,100 degrees
Fahrenheit, is considered to be part of the barrel for purposes of
measurement.  A seam weld extending at least one-half the
circumference of the barrel or four equidistant tack welds around
the circumference of the barrel are adequate for this purpose.

A firearm having a muzzle brake, cap, or barrel extension
permanently attached by those same methods to cover the threads on
a barrel, would not be considered to have a threaded muzzle.
Please note, however, that any muzzle device or barrel extension
which functions as a flash suppressor or grenade launcher would
still constitute one of the qualifying features of a semiautomatic
assault weapon as that term is defined in 18 U.S.C. section
921(a)(30(B).  Industrial adhesive products are not an acceptable
method for permanently attaching a muzzle device."

www.titleii.com/BardwellOLD/atf_letter40.txt

You can also drill and pin the FS in place, but the pin will still have to be welded or soldered over.

If you're ever gonna attach a suppressor to it, look at some of those combination FS/mounts. I think the Bi-lock makes a 14.5 go to 16.

I have a 15" with a 1" Wilson perm attached...  just an idea if you are talking about doing a custom FH anyway.

CMMG offers their 1/7 M4 barrels in three lengths;
14.5" with a perm. Phantom
14.7" with a perm. A2 FH
16" with an A2 FH

An A2 flash hider is 1.25 inches long.

Dude you need to hang in the tech forums a bit more.

Perm attach a phantom or Vortex and you're good to go.

I drill and tap the FS for a 6-32 set screw and drill into the barrel threads slightly. Tighten the set screw down and weld over the top. Basically a modified pin.

Quoted: Dude you need to hang in the tech forums a bit more. Perm attach a phantom or Vortex and you're good to go.

Are you trying to say GD isn't the place for that kind of question?  

Quoted: Quoted: Dude you need to hang in the tech forums a bit more. Perm attach a phantom or Vortex and you're good to go. Are you trying to say GD isn't the place for that kind of question?