I just received an order from a customer with an extremely attractive Ballard rifle chambered in 32-40 Marlin Ballard. He said his rifling twist rate has been measured at 1/16"  I believe the 1/16" was standard for the original rifles intended for use with a 165 grain bullet. Wiki says 165gn was the original bullet weight.
This customer is requesting a 200 grain tapered bullet.
  I shoot the 32-40 in a Stevens model 44 1/2 with what I have always assumed to have a 1/16" twist.  The bullets in question are from a pair of Saeco molds both producing a tapered bullet for breach seating but one at 200 grain and one at 170 grain.
  In my rifle the 200 grain bullet is not being completely stabilized at 100 yards making oval holes in paper. I like to keep my velocity subsonic so muzzle velocity is held at just under 1050 fps for my location at 6000 ft elevation.  Perhaps a higher MV would stabilize the 200 grain bullet but I prefer to stray subsonic for my 100 yard target shooting.
I have shared this information with the customer but have not heard back from him yet.    I understand that in the day the 200 grain bullet was the preferred weight for 40 rod target shooting. 
   I am thinking that perhaps the advanced rifleman of the day just as today tweaked the rifling twist numbers to a faster twist to best handle the longer bullet. This is just speculation on my part going on my limited experience with just one rifle.  I would like to tell my customer with confidence which of the two bullets either the 170 grain or the 200 grain will be best suited to his rifle with a 1/16" twist chambered in 32-40 Marlin Ballard.

What are the band sizes of the 200 grain?
Bob

Sorry but I have nothing cast up to take measurements from. bobw wrote yesterday at 6:14pm:

Statesrights wrote yesterday at 8:15pm:


What is your rifling twist rate ?