doublegunshop.com - home Forums General Discussion Double Rifles, Paradox Guns & Gauge Rifles @ doublegunshop.com .500 x 2.5" calibre information

Hi folks

Am looking to find information on the calibre .500 x 2.5 inch BPE
I have recently acquired a double rifle by James Beattie (London), c.1864, in this calibre and am struggling to find any info on this at all.
Suspect the rifle was made for British officers in India for sporting purposes being a .500.
The only calibre I can find similar is Sharps .500-90 STRAIGHT.
Will keep you posted once the rifle arrives with me, and have considered a chamber cast to check when it does to confirm dimensions. .500 x 3 inch would make more sense as is same as 500 Nitro Express.
I do plan to reload for the rifle if possible and seems it deserves to be shot if condition permits.

Any help much appreciated, I've waded though many cartridge catalogues and not yet found an exact match but thought this is something Double-rifle aficionados will be more familiar and nuanced with. Any help/steer much appreciated.
Pics will follow

Cheers

I saw that gun at auction, looked to be in beautiful condition. The .500 2&1/2" shows up in the Bill Flemming book "British Sporting rifle Cartridges", it shows between 90 and 98 grains of powder and a 340 grain lead bullet.

George A. Hoyem, Volume 3, shows (in addition to the (3 and 3 1/4 inch) .500 cartridges in lengths of 1 1/2, 2 1/4, 2 1/2 and 2 5/8 inch.

All are of Boxer coiled case construction with iron base discs like the original .577 Snider and .577/.450 Martini- Henry rounds.

They may have been designed to drop into the short breech of Snider sporting rifles.

He does not show any solid drawn cases , which suggests they did not stay current for very long.

He does not give any load data but mentions in relation to the 2 1/4 inch that prison guards in New South Wales were reported to use double rifles (“There’s posh for you!”) in a similar calibre.

The dimensions he lists for the 2 1/2 inch are .653 rim, . 580 head, .546 case mouth, .505 bullet diameter, case length 2.5 inch and OAL 2.81 inch. He pictures two 2 1/2 inch cartridges, one with a short round nose solid (presumably the 2.81 inch OAL) and the other with a longer tubed Express bullet.

It would appear to be dimensionally similar at the base to the 3 inch drawn case which will probably work with trimming and neck reaming but look to see if there is a slight step in the chamber to accommodate the base cup of the coiled case.

Hope it turns out to be a shooter Baz, and welcome to the forum!

Thanks SKB that's a helpful steer, I don't have a copy of that book but feels like something that would be helpful. I had guesstimated a load ivo 90grs and was going to start at 80 - so that data is very helpful. Think I will be lucky to find dies for it though! This is all new to me (double rifles) but have been watching them for some time.
This particular rifle looked too good to miss, which fortunately for me many seemed to; although the proof will be in the pudding as they say. The bullet mould is present so am optimistic.

Parabola - thank you for this reply and the technical case details within, that is again very helpful.
I've noted in pics of the rifle that there are some fired .500 express cases there. I wondered (we'll see when it arrives) if the previous owner has shortened these to 2.5" to reload.
As for NSW guards having double rifles, two things struck me, the first round...followed by the second! Certainly a strong message to the inmates!

Could you share an image of these rounds for me?

Hope this works, photo credit to George A. Hoyem

That's great, thank you for that and also George A. Hoyem. Visually and by dimension it appears very similar to the Sharps 50-90 STRAIGHT. The rim thickness is noticeably thicker.
Will post back here once the rifle arrives and share more.
I did think to myself that I'd quickly see if I could buy a copy of both aforementioned books....how I laughed...

Baz Smiles,
The rim thickness of modern solid head drawn cases can be pretty easily adjusted to fit your gun. If you are able to find original ammo, keep it for reference, don't try to shoot it.
Mike

Thanks Mike - noted. I doubt very much I'll be able to find original ammo, but excited to think I might; I would not be tempted to shoot it! Saying that I did feed over 50 rounds of 1940 .303 through my Enfield a couple of years ago; not a glitch!
Am interested as to how rim thickness can be adjusted, are you able to steer/shed any light on how this can be achieved?

Very many thanks to you and other friendly, helpful forum members.

Baz Smiles,
When I need to thin rims( 6,5x58R, 5.6x35R Vierling, .310 cadet, etc), I just chuck them in the lathe, with the rim bumping the chuck jaws( any type or even collet will work) and face them off from the rear. When I find the amount of reduction required, I set a carriage stop to make then all the same. I also set a cross feed stop to center the tool ( turned parallel to the "ways" to adjust initial depth by micrometer dial on cross slide) on the primer pocket and make the cut "out". So I move the tailstock out of the way, chuck the case, bump the cross slide against the stop, bump the carriage against the stop and lock it, make the cut, deepen the primer pocket with a Lyman primer pocket uniformer, radius the sharp outside corner of the rim with a file ( move the case out a little first to keep the file away from the chuck). Repeat the operations until all cases are done then chamfer all primer pockets by hand, doing it by under power can result in taking too much. On the first one, you can section the case to make sure it is not thinned too much. That is a long sentence, but when you are doing the work it doesn't take much time.
Mike

Mike
Thank you for the reply, you may think it lengthy but to me it's usefully detailed and I appreciate the time and thought you have put into it.
I haven't touched a lathe for years so would struggle here; with these details though I know a man who could/can.
Cheers

British cases for the .500 already have very thin rims to the extent that you have to be very careful not to tear them off with the shell holder when extracting from the die even with prober lubrication.

It may be worth getting someone to make you a 360 degree shell holder ( female threaded collar to drop around case and screws on to male threaded shell holder base).

Slower buts saves cases.

You probably will not have to thin the rims

Baz Smiles,
You are welcome. If you encounter the problem described by Parabola, I suggest you de-prime by hand and size the cases with the de-priming assy. removed. Then if the case" sticks" a little, you can tap it out with a dowel or if really bad with a punch and heavier hammer. Parabola's idea is interesting, just be sure the new shell holder is installed before sizing the case.
Mike