W J Jefferys cartridges

Hi Guys
First time on board.

I would like to know what cartridges W J Jefferys invented.
I don’t have the reference material to satisfy this question ,so I have come to the experts for help.

        thanks in advance


These are the ones I know:
255 J
275 J
280 J
303 Magnum rimless
333 Jeff. rimless
333 Jeff . flanged
404/330 Experimental
450/400 3"
404 JEFF. rimless
475 Jeff #2
500 Jeff. ( possibly a Schuler design)
600 NE

May exist others

Thankyou for your help


My nit-picking personality is taking over once again and I can’t help myself.

It’s W. J. Jeffery


Ray you are correct about the name.

However I would like to flag up a strange quirk among the London gumakers in particular of referring to themselves and each other with an “s” on the end. I can offer no reason for it. So they would say “a nice little 16 bore made by Churchills” or Purdeys or Hollands. Its just one of those little idiosyncracies.

There was a gunmaker called Jeffries but thats unconnected


Interesting. It evidently is not limited to London. Colt was often referred to in the USA as “Colt’s”, as in “a Colt’s revolver.” Maybe it rubbed off from his London connection?

You never see a Smith & Wesson’s revolver or a Winchester’s rifle.

I do think the misspelling of Jeffery’s name was because of the other Jefferies. You often see a reference to the 404 Jefferies.


Well, for many years it was Colt’s Patent Firearm Manufacturing Company.