Handguard ID is 1.375”
The flash hider is not pinned. It will require some force to remove it. If it is really stuck, I would advise returning it for a replacement or taking it to your local gunsmith for assistance. It is removable.
TRYBE Defense does not offer a 10.5" complete upper receiver with a lighter barrel. However, we do carry many aftermarket barrel options such as the Rainier Arms AR Match .223 Wylde Lightweight Barrel and many others that can be found by using the link below:
https://www.opticsplanet.com/rifle-barrels.html?_iv_parent-gun-model=ar-15&_iv_parent-caliber=dot-223-wylde,5-dot-56x45mm-nato&_iv_parent-barrel-length=range-10-12-dot-99-in&_iv_gridSize=240
The TRYBE Defense AR-15 10.5in Complete Upper features a 0.750" gas journal size.
Jimmy -- The TRYBE bolts are HPT and MPI, but the barrels are not. The barrels and uppers undergo different testing and inspection processes to guarantee compositional perfection and dimensional accuracy.
No, an FFL is not required to purchase this TRYBE Defense upper receiver.
The TRYBE Defense AR-15 10.5in Complete Upper M-LOK, .223 Wylde, has a Carbine Length Gas System.