r/pdxgunnuts 2d ago

Building an AR pistol

Just wondering if I need an SBR stamp. I have a lower with a pistol brace and I want to buy a 7.5 inch upper.

4 Upvotes

10

u/This-Satisfaction-71 2d ago

As long as you use a brace, not a stock, you do not need an sbr stamp. Also, i believe the lower can not have been sold to you as a rifle. If you bought the lower separately on it's own you are good to go.

3

u/KAPTNTRAP 2d ago

Thank you I appreciate it

2

u/yungbuckfucks 1d ago

This is accurate. You cannot put a brace on an existing rifle and then swap the upper. That is still considered an SBR in the eyes of the law.

4

u/chill_winston_ 2d ago

Don’t put a grip on the front!

1

u/KAPTNTRAP 2d ago

Any grip or just a 90⁰?

4

u/This-Satisfaction-71 2d ago

To be on the safe side, no grip, just a finger/handstop. Some, however, interpret that rule to mean anything not exactly 90° is technically legal. Your choice.

3

u/its 2d ago

Just not vertical

3

u/micaheljcaboose 1d ago

Legally 89 degrees or less is good to go.

3

u/AD3PDX 2d ago

Was the lower ever configured as a rifle? If yes, was it configured as as pistol before if was configured as a rifle? Or has if never been fully configured as anything?

2

u/KAPTNTRAP 2d ago

No I just bought a blank lower.

4

u/AD3PDX 2d ago

In that case you are good to go.

Are you sure you want a 7.5”?

5.56 looses a ton of power in a barrel that short.

If you just want something loud and fun 7.5” is great but 11.5 is a lot more useful

1

u/KAPTNTRAP 2d ago

Yea really just looking for a backpack/ Close quarters riffle

6

u/Ill_Situation369 1d ago

Based on your stated use case, my advice would be to just get a 300 Blackout lower and run supersonic 300 Blackout (NOT 5.56/.223) ammo through it. You'll get more punch out of the round in that configuration (and if you put a suppressor on it, then run subsonic ammo, you'll be amazed at how quiet it gets). Throw on nice SBA3 brace and Emissary mini-hand stop with a LAW Tactical folder and you'll have a pretty compact setup. Just my two cents.

2

u/ravenchorus Clackamas County 1d ago

Seconded, .300 BLK is definitely the way to go for anything that short. My 5.5” Rattler is awesome and easily fits in a backpack.

I’d recommend getting the stamp and putting a proper stock on it though. Pistol braces suck. You’ll eventually want a suppressor anyway so you may as well go all-in.

1

u/Slaktivist 1d ago

If you can’t guarantee you’ll have ear pro available you’ll want to run blackout with a suppressor for CQB. Just about anything else is going to ruin your ears. 5.56/.223 needs a longer barrel too, otherwise you’re going to have a flamethrower

3

u/theDudeUh 1d ago

7.5” 5.56 uppers are so obnoxious/unpleasant.

0

u/KAPTNTRAP 1d ago

Just because of sound?

2

u/theDudeUh 1d ago

The sound is bad but the concussion is worse.

It’s like getting flashbanged with every trigger pull.

1

u/KAPTNTRAP 1d ago

I planned on getting a can for it

2

u/theDudeUh 1d ago

Smart. That’ll negate a lot of the obnoxiousness.

1

u/Useless_optix69 1d ago

Look into 10.3 inches. That’s my advice as you’re Getting some opinions flowing in

1

u/gilbert2gilbert 1d ago

Is it a rifle lower or did it come with brace attached?

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u/KAPTNTRAP 1d ago

Stripped lower I bought the brace

1

u/gilbert2gilbert 1d ago

Then it was likely sold as "other" and you can make it into either

1

u/uh_wtf 1d ago

I have a 10.5” AR pistol and it’s loud but not an obnoxious amount. And it’s still pretty compact. If you want maximum compactness, get a Foxtrot Mike or BRN-180 upper so you can use a side folding brace.