If you're shooting an 'inline' [like the 700] the blast from a number 11 should do. IMHO if I wanted to try this I would use CCI Magnum Percusion caps. The problem with pellet type propellants arises when used in a 'sidelock' where the flame from the cap has to turn the corner to get to the charge. I have used pyrodex in sidelocks by dropping FFFFg [4 grains] to the back of the gun with a special tube. It's a hassle but it works. Wasn't worth the effort cause, for my gun the holy black makes the tightest group, and the pellets shot all over the place. But to get back to your OP yes you can, and kudos to you for checking on advise from a gun store. The guys I've run into at Cabellas seem to know thier stuff, but it's a good idea to check out any advise including what you get here at THR.
