Peabody Martini Mid-Range

[Sir Charles deMouton-Black]

 have a Martini Henry action, formerly a .303, that I wish to make into a mid-range target rifle in .375 Flanged Nitro Express (2 1'2").  I have in mind the Whatcheer or Frogmoor type.  The English medium plains rifle also comes to mind.

My gunmaker has the barrel, reamer & dies, & I have a supply of .30 US cases, and a ton of .303 cases to convert.  I wish to use the heavy RCBS or Lyman .378 bullets.

I would appreciate advice on barrel lenth, profile, etc.  Kerry only does round, but thats no obstacle.  De Haas has the max dia at the breach at 1.18.  I was thinking of a short reinforce, a scallop to 1.00 and then a slow taper to about .875 at the muzzle at 28" long.

[Sir Charles deMouton-Black]

I havn't sealed the pattern yet.  One specific question is, what is the best twist for the 335 grain Lyman cast bullet?

[Delmonico]

The Greenhill Formula will give a good idea, I've got a copy of it at home, if nobody comes up with a better idea I'll dig it out.

[Delmonico]

Why do I need my notes, here check this out?

http://www.answers.com/topic/twist-rate

[Sir Charles deMouton-Black]

Thanks Del.

[Sir Charles deMouton-Black]

For an online Greenhill calculator go to <z-hat.com/twistrate.htm>