The Brownells BRN-180 and 180s is on sale right now. If you every wanted to build a compact AR SBR or pistol that can be fired (more than once) with the stock folded this looks pretty cool. I don't see the advantage of having the 223 Wylde chamber for the 10.5 inch version so I would use 5.56. That being said I don't know shit about 223 Wylde. The buffer is internal so you can use a LAW folding stock adapter and build an awesome backpack gun. If backpack guns aren't fuddlore, I get confused some times. Looking for a COVID-19 project, welp, here is one.
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