I mix up small batches that will be enough for about 6 coats depending on the size of the stock. Usually 1 tbsp of tung, 1tbsp of linseed, 1tbsp of mineral spirits and 1 tsp of Japan drier. Anything more and your wasting it because if it sits for too long it will form a crust, also make sure to use a sealable container for storage. Preparation is the key though. Once the stock is prepped I like to seal it with a 50/50 or even 60/40 mixture of mineral spirits/oil, the linseed is usually better for this due to being a thinner consistency than the tung. This can be brushed on and will dry fairly quickly so you can easily get about 4 coats on in one day if conditions permit. Drying times can be sped up with a dehumidifier. I find that adding the Japan drier drastically speeds the drying time of the oils.

I like to use latex gloves that are firm fitting and just dab a couple of fingers and start rubbing in smooth even coats. For a Mosin Nagant working at a leisurely pace you should be able to do one coat in about 30-45 minutes easy but take enough time to ensure that there is even coverage. I use an eye bolt threaded into the butt plate screw hole to hang the wet stock and provide an extra grip point while working. Wet sand with the finish mixture every other coat with 600 grit wet/dry (my preference). Big tip, ensure that your work area is as dust free as possible.