80% lower to build up a "non-firearm"

[rdtompki]

I need to build up a lower with buffer tube and grip that is not a firearm (for work purposes). It looks like the 80% lowers have the four features I need to avoid any machine: holes for take-down pins, threaded hold for mounting grip and threads for buffer mount. Am I correct in seeing these features on an 80% AR lower? I can't use a blue gun or similar as I need to be able to interface to an AR upper.

[divingin]

Seems to me that if you don't mill out the trigger group pocket, you're not building a firearm lower frame assembly. Drill the pin holes (other features you spec'd will already be done), and you've still got a random chunk of aluminum.

[nicky c]

With an 80% you can install everything including the magazine, except for the trigger group.

[SVT-40]

I need to build up a lower with buffer tube and grip that is not a firearm (for work purposes). It looks like the 80% lowers have the four features I need to avoid any machine: holes for take-down pins, threaded hold for mounting grip and threads for buffer mount. Am I correct in seeing these features on an 80% AR lower? I can't use a blue gun or similar as I need to be able to interface to an AR upper.

Not all 80% lowers have the recess milled in the rear part of the receiver where the rear take down pin rests. You want to find one that does.

The one in the below pic cannot accept a upper without milling. Milling the pocket so a upper can be installed will probably make it a firearm.

[baih777]

There have been versions with the rear pocket for the upper lug to fit.
But if you buy one and mill out the small pocket, it would be considered a firearm.

[rdtompki]

There have been versions with the rear pocket for the upper lug to fit.
But if you buy one and mill out the small pocket, it would be considered a firearm.

Thanks,
I see from the pictures online that "most" manufacturers include the pocket. I'll verify before I order, but that should do the trick. Very inexpensive to add a buffer tube and furniture. I'll probably paint the whole thing blue or orange, but not my functional upper

[mshill]

Interesting. What are the plans.... open carry demonstration?

[rdtompki]

Interesting. What are the plans.... open carry demonstration?

No. Work related. I can do some evaluation at home with a real AR, but all we have at work is an Airsoft M4, albeit pretty realistic in terms of geometry.

[sbo80]

even an 80% with the rear pocket cut doesn't mean it'll fit an upper for sure. Some of them the rear pocket is still a bit too snug, and will need opening up.

[sigstroker]

Thanks,
I see from the pictures online that "most" manufacturers include the pocket. I'll verify before I order, but that should do the trick. Very inexpensive to add a buffer tube and furniture. I'll probably paint the whole thing blue or orange, but not my functional upper

It would probably be cheaper to use a real lower, but then you'd have to pay DROS fees (dunno how much they are). In normalized America an Anderson or the like would be cheaper than an 80.

[rdtompki]

I have stripped lowers, but they are "firearms" and I can't have a firearm at work. You would think leaving out the bolt, ignition parts, etc. I'd be fine, but not so. I'm not even sure, technically speaking, that the airsoft gun is ok, but that didn't happen on my watch.