My .375 2 1/4 Express, "rebored" from .303 brit Martini arrived back today. I see the bore looks nice, but the rifling seems a bit shallow to me. I am used to seeing my heavy lands in my old originals. This has a 6 groove one twist in about 12.5 inches. Should be good for heavier bullets. I wanted to use mostly cast bullets. I hope this shallow groves won't be a problem. The chamber redo looks nice and evenly tapered and polished. There will be little to no neck on the cases. I will start preparing my cases and see what I can come up with. Once I fire form a few I will know.
I went for a rebore to keep the same style and configuration of the Martini Henry barrel. Still lots of thickness on this 22 inch barrel all the way to the muzzle. Can't wait to work up some loads. I don't know if this would be an option for the SMLE due to the straight case. I see by these posts that the taper dosn't seem to be a major issue.