Optimum Twist Rate for .36 cal Roundball Barrel

[max]

Is there an "optimum" twist rate for a .36 cal. roundball barrel?  I notice that some manufacturers only make them in 1:66 whereas others use 1:48.  How about barrel thickness? Is a stiffer barrel better?  Since I'm only interested in match accuracy, barrel length is not a factor except to keep the weight down if I use a say 15/16" tube.

[Don Getz]

I would recommend a 1/48" twist in a 36.  I have one and I know it works...........Don

[Dphariss]

I would recommend a 1/48" twist in a 36.  I have one and I know it works...........Don

I would agree.

48 is a greatly overlooked twist rate for calibers 50 and under.

Dan

[erdillonjr]

A 1/48 is the way to go on a 36 or a 40. I have both and they put them thru the same hole. Ed

[jmforge]

I was playing around with the Greenhill Formula calculator and just for giggles, I plugged in .36 caliber and lo and behold , 1 in 48 came up as the "ideal" twist for stabilizing a slug that just happened to be around one caliber in length.  Now I know that round balls stabilize a bit easier, but that has to tell you something,

[Frizzen]

My .36 has 1-16 twist.   But it's a 7 inch barrel pistol

[Daryl]

Jim - the Greenhill formula was intended to show the 'slowest' twist that would work, not the optimum.  Of course we all know they'll shoot well in slower yet twists, also showing it's anyone's guess as to what's best.  A lot depends on the expected velocities.

[northmn]

The best twist issue has been beat around for some time.  The old Douglas barrels were all 1-66 all shot very well.  I had one in a 32 and thought that a 1- 48 would permit  lighter loading.  There was not a nickels worth of difference. Both liked about 25 grains for best accuracy.  A lot of squirrels were shot with 1-66 twist 36 Douglas barrels.  The 1-48 will do great as others stated, but the 1-66 will likely also do great.  Round ball do not seem to be that sensitive.

DP

[jmforge]

Jim - the Greenhill formula was intended to show the 'slowest' twist that would work, not the optimum.  Of course we all know they'll shoot well in slower yet twists, also showing it's anyone's guess as to what's best.  A lot depends on the expected velocities.

I was using Mountain Mold's calculator, which says it has a "fudge factor" of 1.3 built in.  They did give the old "your results may vary" warning. 
Joe

[Dphariss]

Jim - the Greenhill formula was intended to show the 'slowest' twist that would work, not the optimum.  Of course we all know they'll shoot well in slower yet twists, also showing it's anyone's guess as to what's best.  A lot depends on the expected velocities.

I was using Mountain Mold's calculator, which says it has a "fudge factor" of 1.3 built in.  They did give the old "your results may vary" warning. 
Joe

In small arms using long bullets its generally about 2" short of best twist. I.E. if it recommends a 20 use an 18.
Round balls don't care much.

Dan