Except for my 1987 Colt, all the rest of my AR rifles are mixed up Heinz 57 rifles. I do use a lot of DPMS, Bushmaster, and RRA parts and interchange uppers and lowers as I feel the urge.
The only reason why the Colt doesn't get thrown into the mixmaster is because it is a large pin. It might have a DPMS bcg in it right now, I can't be sure..
One I've used a Seekins Precision SP223 lower and a 13.2" SAR rail. Spikes Tactical BCG, barrel, upper receiver, enhanced LPK, and enhanced buffer tube. It now has a POF 4.5lb trigger in it.
Have a 308 POF lower, CMMG upper, and 15" rail on the way to renovate my DPMS 308. Have a 2 stage Armalite I'm going to throw in there for trigger.
Another build I have going has a Mega billet upper and lower. Going to have the Spikes Enhanced trigger in it (leftover parts). The lower internals are High Standard parts from Brownells. Rainer Arms BCG. Buffer tube is a Tactical Innovations at the moment but since I have to barrel, rail, or grip it's kind it's up in the air if I'll use it
My most recent build (still currently in progress but mostly done)
Lower Receiver Noveske gen 2 lower
Noveske take down pins
CMMG builders kit
ALG Trigger by Geiselle
Vltor Buffer
L.B.E buffer
Magpul 60 degree safety selector
Magpul MIAD
Magpul bad lever
Noveske QD sling plate
Magpul STR or ACS
My builds are RRA lowers and RRA parts. The uppers are either BCM with DD rails (2 of those, different barrel length) or a BCM upper (unmarked because it was stripped) with a Noveske barrel and Troy rail.
My first AR build was a 20" heavy barrel - Essential Arms lower (and I think I got the parts kit from them, too) and Del-Ton parts on the upper. It's morphed a number of times since it was born, and now sports a Magpul PRS buttstock and various other Magpul parts, Yankee Hill furniture, KNS trigger and hammer pins, Harris bipod, Accu-Shot monopod at the back, and other stuff I can't remember at this point. A true franken-gun.
Delaware lower, cmmg lpk, military surplus stock with buffer tube and buffer, used nonamed upper with what appears to be a Colt barrel and a unknown bcg.
Everything went together great and it's shot everything I've fed it.
Not an AR owner but thinking about it. Isn't all the mix of parts hard to sell when that day comes. I mean trying to sell a car that's got a Chevy engine, a Ford door & Cadillac hood just seems crazy. Or do you never sell, just buy the next gadget that you think you need?
Selling never crossed my mind but if you have built a gun with quality parts then you have a quality weapon. If on the other hand you went cheap well that's a different story. I would have no problem buying a frankengun that has been built with quality parts.