Bought 2 barrels, one shilen and one Hart. Both 24 inches long. Am sending one to OTT to be chambered in 6BR, 16-1/2 long for an Encore pistol. Want it mainly as a varmit pistol. What range of bullets would be considered satisfactory for this twist? Heavy bullets to my knowledge won't work. The other one I haven't decided on what I would do with it. It also is bored for 6MM, any suggestion would be helpful. Lou