twist rate calculator anyone

[Funky Bunch]

any got a link to a twist rate calc please

[Redfox]

http://www.shilen.com/calibersAndTwists.html

Redfox

[col48]

try this

 

http://kwk.us/twist.html

 

 

ATB

Colin

[Ronin]

I have a programme on my PC that works out twist rate, let me know what you want to use basically (weight, calibre and MV) and I will punch the numbers in for you.

 

The programme is really for bullet makers and includes other parameters such as core weight, jacket weight, centre of gravity from base etc, but I think it will give you close enough figures for your needs?

 

 

Just advise if you want me to do the math for you.

[Ronin]

Hi

 

I ran the figures andcame up with surprising results:

 

 

140g (.284" bullets) at 3200fps.

 

 

Sierra Gameking - 1.130" length - optimal twist = 1.11.84" (one in eleven point eight four inches)

 

 

Barnes TSX - 1.2690" length - optimal twist - 1-10.54" (one in ten point five four inches)

 

 

Hope this helps - when I saw the results I was surprised - so used to using 1-9 for a 7mm (180g bullets) - but having thought a little the twists both seem "just right" maybe a 1-10 would be best for both?

 

 

 

Have you considered Accubonds ?

[Ronin]

Accubonds

 

work well, do exactly what they are intended for but are expensive.

 

I guess you would have to try them in your own rifle to make sure.

[ejg223]

Accubonds

 

work well, do exactly what they are intended for but are expensive.

 

I guess you would have to try them in your own rifle to make sure.

 

Sorry Pete for barging in,

Ronin could one load develope a load with BT's and then have similar results with accubonds??

BC seems same between the two.

edi

[Ronin]

Guess that would depend on the bearing surface length really - but as always, its down to individual rifle barrels.....