That graphite lube looks like a tube of dry graphite. It's a colloidial form which smears out pretty nice on metal parts, but it's very messy. It leaves a dark streak on anything you transfer it to so be careful cleaning up after application. I like to mix graphite with a blob of white lithium grease to make it more controllable. Apply it sparingly to metal and sliding plastic surfaces and work the gun a bunch of times. Disassemble and wipe it off with a paper towel leaving a very fine dry surface which is very low friction and doesn't adhere to abrasive sand. It's a bit of a pain, but it performs very well.
I find heavier silicone oils do not provide very good lubrication altogether. Silicone is pretty much useless for metal-metal contact because it has no film strength. It also can adhere to sand or dust making an abrasive gun smegma which increases wear which is why I went through some significant pains to find 1.5wt oil to include with my GunGas kits.
Very low viscosity oil does not foul barrels as much as heavier oils. It tends to aerosolize and blast out down barrel instead of accumulating and getting drippy.
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