Got myself a lee 457/340 gr. mold.cut the blocks down to make a 300 gr fn. Polished out grease grooves. poured some.Spun them concentrical to ogive on unimat lathe,and turned them to .452. They almost look identical to 300 gr xtp's which I have great luck with. Cant hit a thing. No matter what kind or how much powder.This is in a savage ML10 II.Ideas would be appreciated.ps.Black mmp and hornady sabots tried

What's the largest dimension of your bore (grooves)? If you can determine that, would it make sense to paper patch those labor-intensive CB's to .001" over groove diameter? ...Maven

On a 50 cal muzzleloader?

Since two brands of sabots didn't work, you can (1)try other brands as one may fit your CB & bore better than the others. (2) Reduce your velocity via reducing your powder charge until you hit the target. (3) Check your scope mounts if you're using one. This is a more common problem than you'd think. (4) Paper patch the CB in combination with #2. Hope this helps, ...Maven

Thankyou Paul

Patch the bullet to .001" over bore diameter, not groove, and use a felt wad between the patched bullet and powder.

Lead bullets + velocity of 2300 FPS or more = no accuracy. Do you know what your velocity is? What powder are you using? I use 45 grns. of AA5744 beneath a 260 grn. Dead Center (with sabot) in my ML II. That's a pure lead bullet and I doubt she would take a heavier charge of that powder.

Charger, try casting them out of Wheel weights and let us know what happens. It could be they are upsetting too much and getting too short for the twist.