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There is a place to fig this out but cant get in.... OK what would be the max length of a conical for each cal. 45, 50,54 all 3 in 1/48 twist. I have no choice GB.

tia Nim
 

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Please post your question about the sabots in 1:48" in the Modern Muzzleloading Forum. ;)

Tim
 

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I don't think they are talking about sabots...I think they are talking about conicals, Maxi-Balls, Buffalo Bullets, etc...

There is a theory, designed for cannons that will tell you what length bullet will be thrown most accurately for a given bore...

In practice, with a muzzleloader, you still need to shoot it to find out...
 

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Nim,
Here is an online chart that may help you, http://www.prbullet.com/chart.htm

The bottom half is where the conicals are listed and gives you an idea of the weight range that will most likely work with the different calibers you asked about.

Good luck with it.
 

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Nim,
I once came across something called the Greenhill Formula, which is supposed to give you a rough idea of the twist rate necessary to stabilize a bullet. The formula is:

Twist rate = 150 * BD^2 / BL
(where BD = bullet diameter in inches, and BL = total bullet length in inches)

(Also note that "*" ="times", "^2" ="squared", and "/" = "divided by")

By plugging in various bullet lengths, you can figure out which length will stabilize with a 48" twist.
For the calibers (bullet diameters) you listed with a 1 in 48" twist, the longest bullet lengths that would stabilize are:
45 cal - 0.633 inches,
50 cal - 0.781 inches,
54 cal - 0.911 inches.
These are only rough guidelines to get you in the ballpark. I have found I can break this rule with some bullet designs, whereas other bullet designs that should work according to the math don't stabilize. Ultimately, you can only find out by trying the bullets in your gun to see if they actually work.
Duane
 

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Here's an online Greenhill formula based twist calculator that allows for the use of different bullet materials, enter the inputs, then click in the outputs for the required twist rate.

Tim

http://kwk.us/twist.html
 
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