Your best bet is to start with a half bottle the let it solidify and check consistency. If its too hard remelt and add more oil. Its a lot cheaper than adding too much oil from the get go and then have to buy more lube. But I guess you could always add some bees wax to stiffen it up.
What Clem said not to mention it helps keep the bullet from moving off the charge! I use to shoot White bullets until I found one halfway sticking out of my bore while stalking. My one grandson had his bullet actually fall out of the bore and all he heard was the powder going off when he shot but there was not much powder in the bbl. Since those days a long time ago, I got to casting my own and sized my bullets .001 to .015 larger than my bore.
Hmmm… for target loads and best accuracy I typically size a .001 or .002 under bore diameter and use either an oversized wad or card over powder. Those bullets slide down bore under the weight of the ramrod and I’ve yet to see significant leading with pure lead, or 20 or 30:1 alloy. I do size over bore diameter for hunting loads because I’m leery of a bullet moving off the powder and causing a walnut or worse…
I shoot paper patched bullets just under bore dia. but full bore I shoot or size about .002 over bore. Same for my alloyed bullets for my 30-30, 375 Win and 45-70
