AR 9mm rules and regs?

[Ghost40]

Alright so for this summers project I'd like to start building an AR9(?). I'm pretty confident with AR 15 laws and regs here in Maryland and federally, I just don't know much about other calibers.
- Are the lowers cash and carry? Do they require 77r (I would assume so)
- barrel requirements (length, hbar)?
- overall length?

Or anything I am missing?

Thanks

 

[94hokie]

I don't remember if it needs a 77r or not, but barrel length and OAL are 16'' and 29'' unless you make a pistol out of it.

 

[outrider58]

Dedicated 9mm lowers are C&C

OAL must be over 29" if it's a rifle or SBR

If rifle, 16" or longer barrel.

Pistols have no minimum length requirement

Not sure about the 77r. I can't remember if I did one or not.

 

[Ghost40]

Lowers are C&C

OAL must be over 29" if it's a rifle or SBR

If rifle, 16" or longer barrel.

Pistols have no minimum length requirement

Not sure about the 77r. I can't remember if I did one or not.

You mention SBR, I am assuming it requires the ATF stamp ?

 

[outrider58]

Always

Sent from my XT1585 using Tapatalk

 

[Major03]

If you go the SBR route...it's the lower that you pay the stamp on. As long as you can take it back to the original caliber you submitted the paperwork on...you can slap more than one upper on it. For example, you could start with a 9mm SBR and then eventually build a 300 BLK or .277 Wolverine upper. Side note: all would need to comply with the MD 29" OAL requirement though.

 

[outrider58]

If you go the SBR route...it's the lower that you pay the stamp on. As long as you can take it back to the original caliber you submitted the paperwork on...you can slap more than one upper on it. For example, you could start with a 9mm SBR and then eventually build a 300 BLK or .277 Wolverine upper. Side note: all would need to comply with the MD 29" OAL requirement though.

Not *with* a dedicated 9mm lower he couldn't.(edited my first post)

 

[Major03]

Oh...yeah...different lowers. Duh. Well, I feel silly.

 

[outrider58]

Oh...yeah...different lowers. Duh. Well, I feel silly.

Don't. He didn't really distinguish what lower he was after. That's why I changed my post.

 

[Ghost40]

Just to clear up the confusion it would be a dedicated 9mm lower

 

[jimbobborg]

Is there a 9mm barrel that isn't heavy profile?

 

[StantonCree]

Just to clear up the confusion it would be a dedicated 9mm lower

I built one not to long ago. I ended up with a YHM Colt pattern lower. It was cash and carry. My upper and internals were all colt accept for the trigger.

Very easy set up and I love it! Shout out to A1Uniform and Mdeng for all the help!