Temporary barrel / handguard on a STAG build

[cr5]

I know that's how the lockup works and the theory behind it, but there are go/no-go gauges for a reason. Don't be telling folks that they can do this and it's safe; it's a semi-auto and things can change between rounds when threaded parts are not torqued down. It's unlikely, but I've seen some pretty strange things happen even with factory-assembled firearms when corners get cut.

Ya, they're for bolt action rifles with adjustable headspace.
It doesn't hurt to use them if you've got them but if the round chambers cleanly it's good. This is assuming that your ammo is in spec as well though and as you mentioned that the rifle is also properly assembled.

It is safe, I know AR-15 armourers that have told me the same thing. Use them if you want but I bet you'll never find an AR that doesn't pass the test if it was built with quality parts.
If you're using Norinco or NEA/BCL parts then I strongly suggest you use the guages.

dumb question coming lol.

Can it be bought separately? Or do it only come with a set of pads., lol

What’s it called?

It's a moly based anti-seize/lubricant. Canadian tire should sell it or any other auto parts store. If you can't find it try the service counter at any auto shop and just ask if they have any extra packets that come with the brake pads. My brother (the mechanic) gave me a handful of them when I asked about it.
Do not use anything with graphite.


The actual stuff is Aeroshell 33MS

 

[Blaintrain360]

Had mine cranked to 120ft-lbs and it never came lose lol.