>And do today's civilian AR15's generally have the manual bolt closure? Most still do, but that is just inertia that is slowly dying out, it is not uncommon fo

>And do today's civilian AR15's generally have the manual bolt closure? Most still do, but that is just inertia that is slowly dying out, it is not uncommon for civilian AR rifles to not include a forward assist, i.e. manual bolt closure. I don't keep up with military rifle configs to know if they still continue with forward assists. >...like the original rifling etc as indicated in the article? There is quite a lot of variety in barrel rifling these days, 1-in-7 isn't uncommon today and with the variety of rounds available, i.e. heavy bullets/light powder(slow) and light bullets/high powder(fast), barrel twist is also highly variable depending on what works best for your barrel length and cartridge selection. Overall the AR platform has moved far beyond Stoner's original design, from the Marines recently adopting a "light machine gun" version of it, to the very short length M4s that is the standard today for the US military. Add into that the huge variety of uses and configurations that civilians use the rifle can wear so many hats. There is actually a really interesting series if you're interested from InRange TV, a firearm YouTube channel, that takes a look at what the AR15 might look like if designed with today's material advancements: https://www.youtube.com/watch?v=vI5NPiicXjE https://www.youtube.com/watch?v=vI5NPiicXjE