Mk18 pin weld

[Hoeyfashoey]

Hello,

in theory, if one bought a dd mk18 upper, pin/welded a surefire comp on it and then pin welded a surefire trainer suppressor to the comp (for a grand total of 16”) would this be legal on a featureless lower? Would there be an anticipated risk to having so many welds or welding a mock suppressor to a comp?

[C.G.]

Hello,

in theory, if one bought a dd mk18 upper, pin/welded a surefire comp on it and then pin welded a surefire trainer suppressor to the comp (for a grand total of 16”) would this be legal on a featureless lower? Would there be an anticipated risk to having so many welds or welding a mock suppressor to a comp?

Supressors are not legal in CA, so you may run into issues where LE may think it is a real one. Why not just a comp?

[tacticalcity]

Suppressors are not legal in CA, so you may run into issues where LE may think it is a real one. Why not just a comp?

You are over thinking it. Barrel Extensions and Shrouds shaped like a suppressor have been around longer than most cops have been cops are commonly sold on California legal rifles right from the manufacturer. Nobody will be confused. If they are you can quickly clear things up just by showing them the rifle, the weld mark, and the barrel extension itself. Up close, you won't confuse it for a suppressor. Real suppressors are more intricate than a barrel extension just shaped similar one.

To answer the OP, yes this will allow you to legally use the upper on a rifle lower and not just a pistol lower. Provided the barrel length with the barrel extension is now 16+ inches.

That said, you can find a new unused stripped AR Pistol Lower one the private market from brands like Anderson, Aero, etc. for around $700-800. You have to go with a maglock, however, they make convertible maglocks that quickly and easily can be converted to function like a normal magazine release button when out of state. While in CA you have to use the maglock to keep out of legal jeopardy and comply with the law. But if you go to Nevada or Arizona to take a course you can turn it into a normal functioning rifle in under a minute. The ones I buy from J&R Sports Supply in Livermore California don't even require tools to convert them. You just loosen the magazine catch about 6 turns, or vice versa.

That said, since I have 3 registered ARs to choose from it doesn't bother me too badly if the new ones are limited to be range queens. It is crazy annoying from a civil rights perspective. Not as much from a practical one. I realize not everyone has registered ARs in their gun safe.

As for the MK18 Mod 1, Colt sells a factory MK18 Mod 0. Have a gunsmith swap out the gas block with a DD MK12 Gas Block and the rail for a DD RIS II and the flash hider for either a KAC N4 or Surefire 4-Prong and you have a clone correct version. It will cost a couple hundred dollars more. Clone correct stuff always does. And the upper with have the Cage Code engraved on it. Some people care about that since most MK18s didn't have that, but supposedly there were some issued that did/do. Therefore, I didn't let it bother me. That said, they both shoot the same.

The complete AR Pistol MK18 Mod 1 I built cost about $1000 more than a rifle version of it would have. The vast majority of that was spent on the AR Pistol lower.

Here is what my MK18 Mod 1 upper currently looks like. I decided to optimize it for night vision over keeping it clone correct accessories wise.


What it briefly looked like.


How it started before the Mod 1 parts were added (with a KAC Rail added).

[ar15barrels]

Hello,

in theory, if one bought a dd mk18 upper, pin/welded a surefire comp on it and then pin welded a surefire trainer suppressor to the comp (for a grand total of 16”) would this be legal on a featureless lower? Would there be an anticipated risk to having so many welds or welding a mock suppressor to a comp?

I did one of these perm attach jobs just last week.
One perm attach to hold the mount to the barrel.
One more perm attach through the locking ring down into the mount.