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This is a follow-up to another thread concerning stabilizing conicals.
Green Mountain .40 barrels have a 48" twist.
Just tried out some soft lead slugs in a 28" long GM barrel, cast from the relatively short (squatty body) Lee .41 195 grain SWC and sized .406".
The conicals were loaded into the barrel like a Lee REAL using hand pressure. Used egg carton over powder wads and lanolin lube.
Fired shots at 40-45 yds into cardboard to check for tipping. 35 grains of FFg definitely showed the beginnings of tipping at this range. Holes from 50 grains of FFg showed greater stability.
The 35 grains may not have had sufficient pressure to expand the bullet base into the GM grooves. So, maybe the 35 grain load is kinda wallowing it's way down the barrel.
Perhaps leaving the front driving band a larger diameter would be a good idea? Perhaps another day will tell.
A 40 barrel with a little bit faster twist, somewhere between 16" and 48", would be really neat.
Green Mountain .40 barrels have a 48" twist.
Just tried out some soft lead slugs in a 28" long GM barrel, cast from the relatively short (squatty body) Lee .41 195 grain SWC and sized .406".
The conicals were loaded into the barrel like a Lee REAL using hand pressure. Used egg carton over powder wads and lanolin lube.
Fired shots at 40-45 yds into cardboard to check for tipping. 35 grains of FFg definitely showed the beginnings of tipping at this range. Holes from 50 grains of FFg showed greater stability.
The 35 grains may not have had sufficient pressure to expand the bullet base into the GM grooves. So, maybe the 35 grain load is kinda wallowing it's way down the barrel.
Perhaps leaving the front driving band a larger diameter would be a good idea? Perhaps another day will tell.
A 40 barrel with a little bit faster twist, somewhere between 16" and 48", would be really neat.