I have several Fast Twist barrels from .45 to .54 Cal that shoot lights out good with Conicals, Paper Patched and Grease Groove, My fast twist barrels range from 1:18 to 1:32 twist, What conical are you shooting? I have 1 rifle that is finicky, it is a Stainless Green Mountain LRH .50 Caliber, this particular rifle will not shoot a Pure lead bullet worth a darn, But when i bump the Lead hardness up to 8 Brinell, and all the way up to 15 Brinell This rifle comes alive! All of my other rifles will shoot soft lead, or slightly hardened equally well. Something about the Stainless? My friend Idahoron has experienced the same thing with his Stainless Green Mountain barrels (Ron runs between 8-9 Brinell Hardness with his Alloy) I am not familiar with your particular rifle, is it a Stainless barrel? If so, Maybe it needs a slightly harder bullet like ours in order to perform well? Also, I absolutely swear by using Wool felt for an Over Powder Wad with any Grease Groove bullet, In my testing, my results were never that great with Hard Card (.060 Vege Fibre) and Grease Groove bullets, Wool felt under the GG bullet base has been the clear winner for me, I seat a Hard Card (.060 Vege Fibre) on the powder, then a wool felt on top of the Hard Card, And seat my bullet. The Hard Card might not be needed? But sure hasn’t hurt anything in all of my testing. I feel the most important part is having the Grease Groove bullet on top of a Wool felt Wad.