30 cal for barrel, 45 for chamber gotcha.
I dont know if the tension is set right, dont know how to tell.
the stock.....there is a backwards R next to the crossbolt, an O in a diamond, a P by the buttplate, 2 weird lookin 6 in circles, and what looks like a line in an O.
I cleaned out all the cosmo from the receiver/barrel and bolt, the stock I just wiped with a sponge and hot water .
EDIT-- And welcome to the forum!