Optimal twist?

[Fastleo]

What do you guys recommend for optimal twist for .58 cal round ball? What groove depth?

All the best!

Andy

 

[waksupi]

I like 1-66, and grooves .012-.015.

 

[Nav]

A ball doesn’t benefit from a lot of twist like a conical does.

 

[Rifleman1776]

This is a never ending debate issue. My preference for round ball is 1:48" or 1:56".

 

[Nav]

Stable is stable. You can only get to zero. It barely takes any twist to stabilize a ball. You would have to spin it so fast the lead would deform or fly apart to over spin it, and that probably wouldn’t even be possible with a patch.
A round ball is a terrible bullet shape with horrible drag and tremendous turbulence. Most calibers and loads, no matter what you do, are going to go transsonic at under 75 yards. Fortunately round balls barely notice that. The ballistic coefficient is worse than a .22, but it IS an incredibly stable shape that requires less twist than any other. In this case the maths are very clear, and it doesn’t matter as long as it leaves the barrel with some twist.

 

[64Springer]

^^^Well stated.^^^

Hard to keyhole a round object.

 

[Fastleo]

I like 1-66, and grooves .012-.015.

Thank you for the advice!

 

[tenngun]

1/48 was the preference to American gun builders during the American ml rifle period

 

[nkbj]

For a .58 bore with round ball, something around 48" to 60" twist and around .01" on the grooves.
Having narrow lands on a .58 was a new experience for me. If the boring on the barrel was less than perfectly smooth to start with then wide grooves are so much the better.

 

[waksupi]

Thank you for the advice!

Someone had to actually answer the question! ;o)

 

[longcruise]

I'd say a 1:66 and around .010 deep on the grooves.

@nkbj mentioned narrow lands which has shown to be beneficial in the accuracy department.

 

[shorthair]

72" twist or slower with 0.010 works well out to a couple hundred yds with a pretty for me on paper.