Bbl contour/twist? And how big is the float? I ask because very light and very heavy bbls can benefit from extra support in the stock. And a float that isn't big (the "dollar bill" spacing) isn't serving its purpose when stock/bbl have an easy chance to contact.

Anyways, screw the 400. You're looking at 20 bucks in components to develop a load after a 1-time investment in tools. Then you're throwing money away when you can roll your own for 10 bucks a box rather than 60, or whatever the 'custom' stuff is.

Also, a 2nd on the fouled bore. Give it a try, this ain't muzzleloading--clean it after 50 or 100 shots, and spotless isn't what I look for in the bore.

Good bullets seated nearly to the rifling, with a hefty dose of '22 should get you where you want perty quick.

Shoot more and worry less--Roll your own.