450/400 x 3 1/3" Nitro Express Purdey Double Rifle. Snap rotary Underlever Sidelock Non Ejector Double Rifle Ideal for Buffalo but probably a bit light for Pachyderms. Holland & Holland were the main recognized producers of English Rifles. Purdey concentrated on making shotguns therefor making less than 500 double rifles by 1960. The above calibre was a nitro developed from the original black powder one. Purdey only made 5 only in this calibre, but i was told that they are making a new one in this designation. i.e VERY RARE! Finished in November 22 1911. Whitworth Steel Barrels.