JACKETED BULLET TEST
With my Savage rifles and barrels, 1 Shilen barrel in 22-250:
After a sum of 7 years of testing, I have been unable to find any combination that will reliably shoot under 1.5” for 5-shot 100-yard 5-group averages.
After 20 months of testing I’ve concluded that in 223 Rem and 22-250, jacketed bullets will group well under 1” for 5-shot 100-yard 5-group averages with a cast bullet powder, Titegroup, at cast bullet charges/velocities.
Jacketed bullets shoot more accurately than cast bullets, and I’m convinced that no amount of weighing, measuring or adjusting will make cast bullets shoot as accurately as jacketed.
The difference is in the bullet. Cast bullets do not look like jacketed bullets, they’ve got grease grooves and flat/round points and they’re softer than jacketed bullets.
Harder bullets could be made of zinc; cast, or for experiment, lathe/screw machine cut from zinc rods.
https://www.boatzincs.com/zinc_rods.html
3/8” X 36” zinc rod, $14.08
Hardness Mohs scale;
Lead: 1.5
Zinc: 2 or 2.5
Brass: 3-4
Specific Gravity: grams/cc
Zinc bullets weigh ~ 65% of lead bullets
Zinc melts at 787 degrees F
I’m not a machinist, and can’t cast anymore; but I can and will pay for that work to be done.
I would be happy to supply zinc rods for any of you machinists to cut into .308” diameter bullets with a simple point.
If turned zinc bullets work, I’ll get a mold maker to cut a mold.
OR
Gas checked lead alloy bullets with a shape approximating that of jacketed bullets might work.
I’ll buy the mold if someone will cast and do the shooting.
The cast lead bullet in my mind is a .308” cylinder .8” long, pointed at one end with a ~3/8” long taper, and a gas check shank at the bottom
The zinc bullet is the same, with no gas check shank.
Either should stabilize in 10” twist.