Someone please explain all the interest in "Uppers" and "Lowers"

[Big_Blue]

Can somebody explain all the forum traffic about Uppers and Lowers? I sometimes think I'm on a Dentist forum. Please relate your explanation to someone who's background only includes shotguns and handguns. I qualified on the M16 in the Air Force but never got involved in repairing them. Do the ARs break down a lot or are people assembling them from scratch?

Thanks

 

[Teefman]

People are assembling from scratch. Its cheaper than buying as a whole...well at least it was before all the crazy prices. I built my own AR and I saved a lot by doing so.

 

[WC1911guy]

The AR platform's nomenclature is defined in 2 separate pieces. The upper and the lower. They can be mixed and matched as needed. The lower is the part considered to be the actual "gun" part of the platform legally.

So many do build from scratch or swap uppers to different lowers. Many lowers are multi caliber so you can use different caliber uppers.

 

[Zastava]

http://www.theoutdoorstrader.com/threads/355865-Question-Why-do-you-guys-buy-and-deck-out-an-AR

 

[Reaper76USMC]

AR's, being so easy to build from scratch and customize into thousands of different variations, are the lego sets of the gun world, so really, we're all just collecting more lego's

 

[joeylee]

What can a 7.62x39 upper fit into?

 

[B. Byrd]

I thought it was like "uppers" and "downers".

 

[1clearshot]

AR's, being so easy to build from scratch and customize into thousands of different variations, are the lego sets of the gun world, so really, we're all just collecting more lego's

Upper and lower Lego halves...

 

[Reaper76USMC]

Upper and lower Lego halves...

What lower is that? I ran across that one once before and have been looking since.

 

[bluesman2a]

What lower is that? I ran across that one once before and have been looking since.

Looks like maybe a Seekins billet?
http://www.seekinsprecision.com/ar-lowers.html