JKR
06-01-2021, 04:19 PM
My apologies if this has been discussed ad nauseam already,
Does anyone give any creedence to twist rate stability calculators similar to this one?
https://bergerbullets.com/twist-rate-calculator/
I was able to google the ballistic coefficient of a 575213 PH minie ball which is .145, I know the typical 575213 bullet is sized to .576, weighs in at 565 grains, is 1" tall/long, guesstimated velocity at 950 FPS, twist rate at 48, standard ambient temperature and elevation of 1000'. When I run this number the stability is "marginal".
Playing around with this I found that decreasing the bullet size in weight to 450 grains and height to 3/4" the comfortable stability increased drastically.
So what do y'all think? Is this calculator bunk or are there some sound physics that can be learned from this calculator.
Does anyone give any creedence to twist rate stability calculators similar to this one?
https://bergerbullets.com/twist-rate-calculator/
I was able to google the ballistic coefficient of a 575213 PH minie ball which is .145, I know the typical 575213 bullet is sized to .576, weighs in at 565 grains, is 1" tall/long, guesstimated velocity at 950 FPS, twist rate at 48, standard ambient temperature and elevation of 1000'. When I run this number the stability is "marginal".
Playing around with this I found that decreasing the bullet size in weight to 450 grains and height to 3/4" the comfortable stability increased drastically.
So what do y'all think? Is this calculator bunk or are there some sound physics that can be learned from this calculator.