An MTM funnel/drop tube kit, or a nice brass spout funnel (forget who made the two I use).
Your funnel is suffering from being past its prime, used for multiple calibers and maybe too sharp of a chamfer.
I generally don't use funnels, but IMR 4198 in the deuce is a place to use one, I guess.
I'm no load expert by any means, but going deeper with that TSX should close the group up, although if the third shot always opens it up to 3/4 I'd not lose sleep.
The 12 land barrels of old are kinda rough, if that's what you have, so mixing gilding metal and the copper TSX during one session may not be a recipe for one hole groups for either bullet.
Re-adjust that seater stem down past the crimp and re-set the lock ring for more latitude. You certainly will never need the crimp.
