Howdy i have been trying to get a rifle to be constant at 100 yards but so far no matter what i have done it still sprays all over the place.

Bullets have been cast by me out of wheel weights with some 95/5 for fillout.

The weight has been from 200 to 260 grains,both with hollow points and solid,plain base bullets.

They will tear up a target at 25 to 50 yards but just flat suck at 100.

I use 2500+lube and have sized .429 and .430.

I also have tried all of the powders that most manuals say are the best to use.
So far it does not make any difference if shooting slow or fast.
With jacketed bullets it shoots lights out at that range.

Any ideas?