What's the twist on that Numrich barrel? My thought is the bullet may be a bit long to stabilize. Also, how ya gonna lube that thing and get it started down the bore? Is it a bevel base wadcutter? You're essentially trying to use the wadcutter as a REAL bullet except that the REAL bullets are pretty short for caliber. I would also have questions about 100 yard accuracy if the twist isn't fast enough to stabilize the wadcutter and I don't believe 30-35 grs. is going to equate to a very high velocity with a projectile approxiamtely 1/3 heavier than a 340 round ball. BUT....try it, who knows, it may shoot like a house afire! I believe if it were me I'd use a lubed, felt wad under the bullet. If you do try it, I'd like to konw the results.
Vic