The net result today is - slug the bores. But yeah, that's what happened.

I had a discussion with David Little at Kynoch about this not long ago. He said that the original factory drawings for the .450/.400 3 1/4" NE, which preceeded the 3", show a .408" diameter bullet. When Jeffery introduced the 3", he did his own thing like he did with the .475 No. 2. That was a bad mistake, and confusion ensued. The "standards" were a .408" for the 3 1/4" and a .411" for the 3", but that was too confusing to last.

My Watson Brothers 3 1/4" was .411", my A. Hollis & Son 3" is .408". In the last month, J. J. Perodeau has slugged two .450/.400 3" rifles for guys I know. An A. Hollis & Son was .411" and a Manton was .408". Another friend has a 3 1/4" that is .405".

The standards were different, but I think Kynoch, in trying to get a handle on this mess in later years, stuck to neither. I've pulled bullets from several lots of original Kynoch in both calibers over the years, all post-war stuff from the '50s, '60s, and '70s. Every bullet pulled from both calibers has been .410".
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