Thompson Center barrel weirdness?

[QuarterBoreGunner]

Stopped by one of the local shops to pick up a gift for a friend that's getting into shooting and saw a early Thompson Center in the consignment case. Nice, with what looked like a 8" .357 barrel. Also comes with a 10" .222 and a .45LC barrel. Talked to one of the guys behind the counter and he said that the .45LC barrel has a weird muzzle attachment and boy he wasn't kidding.

It threads into the barrel (which is ported) and appears to be nothing more than a straight rifled section of barrel.

Take a look and someone tell me what the heck this thing is.

Thompson Center barrel fixture pictures.

[SFFRONTMAN]

.....grenade launcher attachment??? I don't know but thats seriously a weird looking extension. Maybe since its a 45lc barrel, that is a choke/ muzzle brake attachment to allow you to shoot 410 out of it??

[ke6guj]

it looks like a choke tube. Some of the .45LC barrels will also chamber .410 shells. If the barrel is under 18" you will run into Short barrel shotgun issues in CA.

[VegasND]

It was designed to fire a shot cartridge similar to the .22lr in design. The idea behind the straight rifling was that it would stop the spinning of the plastic capsule which held the shot. It would also cause it to break up freeing the shot and getting a better pattern than the shot would normally get due to the rifling. With the 'choke device' unscrewed from the barrel, it would fire a .45 LC normally. I haven't seen one in years.

[ke6guj]

At the bottom of the page, there is a pic of a choke tube.

http://www.tcarms.com/firearms/g2ContenderPistols.php

[SFFRONTMAN]

Sweet, my guess was right, and I love the big ".45/410 Models include removable choke Tube and wrench. * Not for sale in California." Right below it.

[ocabj]

A friend of mine had a TC custom shop barrel made chambered in .45LC that would not chamber .410 shells so it would be CA legal.

[QuarterBoreGunner]

That looks like it except its external as opposed to external like the one on the T/C page.

So wait a minute, is this legal then?

[SFFRONTMAN]

If it can chamber and fire a 410 shell, then it is illegal. You run into short barreled shotgun territory which is a big no no. I *belive* constructive possession also applies to sbs so even possessing the barrel while not attached to the gun is stil illegal. I would then recommend you destroy the barrel somehow.

[QuarterBoreGunner]

Interesting, I'll pass the info along. Like I said, this is at a local shop in the consignment case.

[bwiese]

Yup, smells like a 410 or 45LC/410 bbl.

If it chambers a shotgun shell (410ga) then it's a no-no and the dude should dispose of the bbl.

If it is (as one poster described) a unique way of dispersing shot for a pistol-caliber shotshell, then that's legal.

[ar15barrels]

That's a "hotshot" barrel.
They used a pistol cartridge with a plastic shot capsule.