What is a good temp range for this application?

I have access to Molykote SK-623 (30-302°F), will this work or should I find something 500° or higher?

Aero Shell 33 MS meets the mil spec
Small jars are available from Umbrella Corp or on Ebay.
Tubes from aircraft maintenance supply houses.

Thanks!

I use High Temp Royal Purple it's drop point is 600 degrees. Works great and it's free from my work! (power plant)

Royal purple makes good stuff, I ended up using supertech wheel bearing grease. a member here just made a video on suppressor temps and done readings of the barrel and Gas block area.

Thanks for the replys!

Amazon has it too

According to the spec sheets on Aeroshell and Royal purple high temp it looks like the RP may be better for barrel nuts. I will look again. I know Aeroshell is the "Mil-spec" just for a grease comparison in this specific application.

Don't burn me at the stake, All Ye Apostles of Aeroshell

Does the Purple meet MIL-G-21164 standards?  The TM calls for that kind of grease, whoever makes it.  The spec calls for a white lithium-based grease with about 5% molybdenum disulfide, with particular viscosity and temperature characteristics.  These greases are used specifically for high pressure and temperature applications where aluminum and steel are fastened together.  Most importantly, the barrel nut is not a moving part requiring the kind of lubrication Royal Purple is so very good at.  It requires an assembly grease.  A better substitute would be a product like Dow's Molykote G-N, which is formulated for assembly rather than moving part lubrication.

My last build, an Aero Precision M4E1, I used some 30+ year old high temp wheel bearing grease.
Am I going to die?
Seriously, it is to prevent galling during assembly and not lubrication during use.

Motoguzzi,

You may not die but your barrel will probably just fall off one of these day!

I use High Temp Royal Purple. I'm sure my barrels are going to snap off any day now!

not allowed in a technical forum, warning issued. - Roadhawk

Just grab some Aeroshell 33 off ebay, I got 6 30 ml small containers of aeroshell shipped for like $5, and I only used small container after assembling 3 ARs.