I'm looking for advice for an unusual cartridge:

I just got a nice Austrian rifle, built between 1890 and 1900, Martini system, full stock, nitro proofed.
Dies are available from RCBS.
I have empty RWS 9.3x72R cases for reforming, also the right .364 ca. 193 grain bullets from RWS and S&B. Paper-patched 200 grain .357 bullets might also be an option.
I will use 9.3x72R loads published by RWS, somewhat scaled down do account for smaller case volume. And I will use the Quickload program as a guidance.

This all looks pretty much straightforward, but still I would welcome any advice or experience on loading data.

Thanks,
Martin

martin f
In my 4th edition of Cartridges of the World it lumps all the various older straight 9.3's together, from the 9,3x48R to the 9.3x82R.
It shows a factory load for the 9,3x57R with a 190gr. bullet at 1700fps.
It also states to use 38-55 loading data.
With a 220gr. bullet the Hornady Manual shows a starting load of 29.9gr. of IMR3031 for 1450fps.,
to a max of 34.7gr. of IMR3031 for 1700fps.
Hope this helps.

Why just not back of a bit from orinary 9,3*57 loads?

http://www.norma.cc/nladdtab/93x57.htm

Kimmo

Thanks for suggestions!

The rifle has a Martini action, but of very slender construction (not a bulky militay action). In addition, it has a take-off barrel, 2 lugs under the barrel, one crossbar similar to a period shotgun. Original proof marks were for black powder only, then between 1940 and 1945 the rifle was proofed for nitro powder.
So I want to stay at very moderate pressures.

Quickload gives as max. pressures:
.360 NE 2 1/4" 2450 bar
9.3x72R 2000 bar 29007 psi
9.3x53R Swiss 1800 bar 26106 psi
9.3x70R/360 1200 bar
8.15x46R 1650 bar
.38-55 2400 bar 34809 psi

Old 9.3x72R (and also 9.3x53R Swiss) loads in the 1800 to 2000 bar range are STOUT, pushing the 12.5 g/193 grain bullet to 660 - 680 m/s (2165 - 2230 fps), to be used only in STRONG rifles.
The last surviving mild RWS load for the 9.3x72R was published as ca. 600 - 615 m/s (1968 - 2018 fps), at around 1500 bar.

My guess is I should aim at pressures between 1200 and 1400 bar, and a v0 of ca. 550 m/s.

Comparing RWS loading data for the 9.3x72R and Quickload data for the 550 - 600 m/s range, there are some discrepancies (you should not completely trust QL, especially for straight cases).
And QL suggests that the powders listed in the RWS book (Rottweil R902, R903, R907) do not burn properly with light loads. I should look at the most offensive rifle powders, like R901, possibly also at progressive pistol powders.

According to QL, possible loads might be between:
30.2 grain R901, v0 534 m/s (1753 fps), pressure 1242 bar
31.7 grain R901, v0 559 m/s (1835 fps), pressure 1374 bar
Cases are still more than 60% full, combustion rate is higher than 80%.

I still have to order my dies first, plenty of time for more thinking.
I will certainly chronograph my first loads, and report here.

Regards,

Martin

[ 06-04-2003, 10:30: Message edited by: martin f ]

@Carcano,

addendum to the 9.3x53(R) Swiss:

I do not have any recent loading data for this, only the max. pressure given in Quickload (1800 bar).

But in an old book (Luchsinger 1951) I find these numbers:

9.3x53(R) 13.1 g bullet v0 695 m/s pressure 1810 at
9.3x72R 13.1 g bullet v0 680 m/s pressure 1810 at

A Quickload simulation suggests that pressures will approach 2000 bar.
In ballistic terms, these loads will be quite close to any 9.3x57 (Mauser) load.
They may (as other old European data) be very "optimistic".

Do you have seen any current loading data for the Swiss cartridge?

Regards,

Martin