Could work fine. Hopefully they will match your bore diameter. .001 over bore diameter seems to be a rule for cast bullets. And, sometimes they use harder lead and lube to avoid damage in shipment which is even more critical to CB performance. 10 grains of Unique give me @ 1200 fps in my .308 with that weight bullet. If you want sub performance, start with about 5 grains of Bullseye, and drop it .5 grains at a time until you stick a bullet. Push it out and go back up .5 to 1.0 grains or so. That will be about as low and quiet as you can get. If you are going to use the .308 on critters, I'd rather use a 180 to 200 grain bullet. Mass helps penetration. JMHO