I always wanted a T-91 build because they look cool. I’ve got lots of 3D printed AR lowers. Figured I’d get a T91 upper and print a lower for it. Works pretty great!
The T91 is an interesting piston-based AR15ish system that Taiwan uses. It’s heavier than a standard AR, doesn’t really shoot any smoother, and like anything that changes up the standard AR gas system, it doesn’t like to run steel case ammo.
But paired with a 3D printed lower (the UBAR2 in this video) and a 3D printed brass deflector (some deflectorless ARs sort of still do 9 oclock ejection, the T91 is more like 11:30 and right into a left handed person’s face), it’s a pretty fun package to shoot. If you’re into AR building I’d probably recommend doing a T91 build, though for what they cost one of the bufferless Foxtrot Mike upper is probably a better buy.