I shot 50 rounds one time wearing a really thin t-shirt.
The only casualty was the shirt, since it was July and about 175F outside. The cosmoline sorta flowed a bit.
Yer sposed to clean the cosmoline out before you shoot it the first time LOL
Texas Sun in Aug gets it out real well.
You cant bake out cosmoline on a mosin nagant in the Wifes oven.
She is gonna be pissed if you even try it, and the dang 91/30 wont fit in there anyway.
I stuff the parts in a heavy duty black lawn bag at set it in the Texas Sun.
Then get one of them family packs of paper towels LoL (Shop towers are better), and a shot of Berrymans gets the tiny places clean.