[Kurzhaar]

Ok, now that the HK bug has bitten...

I'm wanting to get a USC that I can use my AAC TiRant-45 on. I have a NFA trust and already have the supressor. The more I read about having the barrel threaded the less I'm understanding the process. Does threading change the 922(?) compliance? If so, should I just go ahead and SBR the thing?
Anyone using this configuration please offer suggestions. Optimal barrel length? I've never SBR'd a gun before, is it much different than buying a supressor?
So just buy the USC and send the whole thing off? Any guidance greatly appreciated. Sold one of my AR's today to get this moving.
Thanks in avance for the help.

 

[fordemti]

You can buy an HDPS barrel already threaded now for like $300 I think. Check out Ed's website. That's the easiest way to sbr it following getting your stamp. Are you wanting to do the whole UMP conversion? Or just sbr it?

 

[Kurzhaar]

Being new to HK products I don't know what the conversion consists of. I've seen them advertised but honestly don't know enough about it to answer. Would one have the conversion done to be 922 compliant?

 

[jdonovan]

Does threading change the 922(?) compliance? If so, should I just go ahead and SBR the thing?

You need to comply with 922 when you have 2 of 3 'evil features'
high cap mag > 10 rounds
pistol grip
threaded muzzle

So putting a threaded barrel on will cause you to need to comply with 922, assuming you've are going to do the rest of the conversion and put the UMP lower on so you can use high cap mags.

SBR does not change your need to comply with 922.

922 compliance is met by replacing non-us made parts with US made parts.

I've never SBR'd a gun before, is it much different than buying a supressor?

To "sbr" the gun, you fill out a form 1, wait 8 months and the buy and install the short barrel.

The 45acp is going to almost assuredly be supersonic out of a 16" bore. If you want to effectively suppress it you are going to need to shorten the barrel.

 

[Kurzhaar]

Thanks for the clarification jdon. Between your reply and further internet searching it's starting to make sense. Looks like at least an SBR is in my future and possibly a conversion too.

 

[kabob]

Hkparts.net was kind enough (well, from a business perspective) to do a 922(r) list: HK UMP 922r Compliant Parts - HKPARTS.NET