What gr bullet to use?

[TrevorW]

Hello , I am new to reloading and was just wondering if someone could help me out .
I have a Ruger Mini-14 with a 1-10 twist barrel so I was wondering what grain bullet would be best suited for the 1 in 10 ?
Thanks

 

[sunray]

Must be an older rifle. Current Mini's use 1 in 9. Not that it'll make much difference. I'd start with a 55 grain bullet, but try 62's as well.

 

[TrevorW]

Must be an older rifle. Current Mini's use 1 in 9. Not that it'll make much difference. I'd start with a 55 grain bullet, but try 62's as well.

Cool , thank you , yes it is an older model , It was made in the 80's I believe!
I picked up some 55gr hp today !

 

[ciphery]

Google search "Greenhill Formula"
You input your bullets dimensions do some simple math and come up with an appropriate twist rate.
Hope this helps
I think its something like;
Bullet length in 0.000"÷bullet Dia. In 0.000"=A
150÷A=B
B x Bullet Dia. In 0.000"=1 turn in ? Inches.

Now you need to know the dimensions of your proposed bullet and match the final result to your barrel.
I'm not sure but there may be a better way of skining your paverbial cat. Perhaps another CGN'r has a better formula to share.

 

[SUB MOA]

I have a customized Mini-14 with a Gaillard 1-9 barrel. The chamber was optimized for heavier match bullets, I use 69 grain Sierra Match Kings with 25.5 gr of Varget for 2950 FPS.