TC does make the Shockwave in 45, it's a 250 grain bullet. However the BC is significantly lower so I don't use it (but it is accurate in my
You have an Omega with a 1-20 twist? I didn't know they made one! Those twists are very, very hard to find a bullet that shoots well. Long and heavy is all that works. The 200gr Shockwave might work, as might the Precision Rifle 240 and 260 grain .40 Dead Center bullets. The 195 grain .357 is great too if it will shoot for you, but the lead bullets won't go as fast but have a higher BC than the Shockwaves.
The 1-20 twist would be great if we had access to .45-.308 sabots and used some hi-power bullets of higher BC, but I can't find such a sabot.
If you want some bedding suggestions, let me know as I did mine myself and it turned out well. It greatly improved stock fit and consistency of POI after removing the action for cleaning.