If so, what kind of velocities have been achieved with what kinds of powder? any pressure signs?

Perhaps somebody has an old Vihtavuori manual showing data for the 285/286?

Thanks!

Have someone with QL work it up for you.

It has been posted on another forum that 9,3x57 data is interchangeable, at least with 250g bullets at 700m/s with N140

Sure, that data would be interchangeable and you end up with an even more anemic cartridge. OP is looking to maximize the potential of that round.

These two were designed for, and sold to, moose hunters, not African colonists. The perceived potential is unlikely to equate with reality in an ancient mosin or converted Tsarist 1895.

Like you, I’d be keen to see QL predictions, as the European load data I’ve access to doesn’t list 286g bullets for this round.

You might be underestimating the strength of a Mosin. I've done a lot of work with them and done a lot of very unique calibers on them. Basically, they are stronger and safer than any Mauser, I find.

Well I did have somebody run some QL data and 2350 fps with a 286 seems very achievable at 56k psi which is the pressure max for the 7.62x54r.

2350 for a 286 is about mid range of the 9,3x62.

quote:

Originally posted by GBE:
It has been posted on another forum that 9,3x57 data is interchangeable, at least with 250g bullets at 700m/s with N140

The strength of the rifle is not an issue. The brass will give before the gun, most likely at the primer.

I have an old article on the 9.3x57mm by Dieter Sturm. He was using two Mausers in that caliber. He has many loads listed but his top loads are these:

270 Speer, 47.0gr of IMR-4895, 2205 fps (remark: maximum)

232 Norma, factory load, 2330 fps

232 Norma, 48.0gr of IMR-3031, 2485 fps (remark: maximum but accurate)

258 RWS, 46.0gr of R-902, 2115 fps (remark: RWS data)

286 Norma, factory load, 2070 fps

286 Norma, 44.6gr 0f N-201, 2067 fps (remark: Norma data, maximum)

293 RWS, 47.0gr of R-903, 2001 fps (remark: RWS data)

Note that he bested the factory 232gr load by over 150 fps. He wasn't able to best the factory 286gr load.

The brass will certainly cause a problem before the Mosin action has a problem.

However, if we assume for the moment that 9,3x53r brass is made differently than 7.62x54r brass (btw, they are the same base case the Finns just chose to designate as 53r instead of 54r). Necking up 7.62x54r brass would appear to solve the problem given that it is based on 56,565K psi.

As any FYI, the 9,3x57 data I found from Norma is only loaded to 43,500 psi which means the 7.62x54r case is rated at 130% of these loads. I am not suggesting stuffing 30% more powder into these loads but it would seem 9,3x57 in any kind of moderately strong bolt action with any reasonable quality modern brass could be loaded to achieve a 10% increase in velocity.

What engineering analysis am I missing?

Mike -- Let's look at some things.

First, a 10% increase in pressure does not equate to a 10% increase in velocity. I cannot find multiple loads with pressures listed for the 9.3x53R or the 9.3x57 but I do see some for the 9.3x62 in the A-Square Handloading Manual. So I will use a couple of those to illustrate the issue.

A-Square lists four loads using IMR-3031 and their 286gr bullet. The slowest uses 53gr of powder for 2277 fps @ 43,100 ft-lbs. The fastest uses 56gr of powder for 2406 fps @ 52,300 ft-lbs. So, a 21.3% increase in pressure only resulted in a 5.7% increase in velocity. Similarly, using H-4895, a 19.1% increase in pressure yielded a 5.4% in velocity. With RL-12, a 18.8% increase in pressure only resulted in a 3.9% increase in velocity.

It is a known principle. I do not have data for the 9.3x53R but I could list examples using a hundred cartridges I can find data for.

Making a best guess, I think a 30% pressure increase in the 9.3x53R cartridge might result in something like an 8% increase in velocity. That's more than a little but less than 10% and comes only when pushing things to the theoretical maximum. Fire-formed brass is weakened brass. Reloaded brass is weakened. Now shoot it from a fouled bore under environmental extremes and ........ There are sensible limits.

Second, the pressures I listed above were measured in CUP using a copper crusher. Transducer (piezo) measured values vary considerably from crusher values. For any given cartridge transducer numbers are generally much higher than crusher numbers even though the actual pressures being measured are the same. CIP lists the maximum average pressure for the 9,3 x 53 R Finnish, drawing dated 95-03-09 and revised on 02-05-15, and measured 25mm from the chamber as 3400 bar (49,313 psi). CIP indicates they used the transducer method. Remember, a the psi value from a crusher measurement is going to seem low when compared to the much higher comparable transducer value even though the pressures being measured are the same. For example, CIP max average pressure for the 7.62x54R cartridge is 49,347 CUP and 56,604 Piezo. Which pressure measurement method are you using crusher, transducer, or both?

Third, Quickload pressure estimates are just that - estimates. My personal experience comparing actual big bore Pressure Trace measured values to Quickload estimates showed that Quickload was underestimating pressure significantly. Quickload is notorious for sometimes estimating pressures way over and sometimes way under depending on caliber and the particular powder. The Quickload program includes a way to enter actual measured pressure values to "correct" pressure estimates for powders and loads but it's a PITA to do so I've never bothered. Quickload gives us good starting points, powder comparisons, velocity estimates, and it provides a good database for the loads we work up. However, pressure predictions are not its forte.

49K CUP and 56K (piezo measured) PSI are the same thing.
I have the solution; just make it in 400 Jeffery. That way you have 90 grains of powder space to play with, and make it to whatever pressure you want. Don't have to cram ten pounds of crap into a 5 pound bag.
Lots more fun and lots more powder, blast, recoil; after all, its a real rifle. I can never understand the lure of silencers or recoil reducers. Like Elmer said, "I want my rifles to kill on both ends."
Yes I can make it feed.

All I was trying to point out, Tom, is that comparing stats that say "psi" doesn't mean much unless you know if the numbers are CUP or piezo.

I know; no argument here.

Mike,
For what it's worth, I found the 3rd edition of the Vihtavuori Reloading Manual, published in 2000.

• For the 9.3x53R, it lists one recipe, for a 255 grain Sako bullet. The maximum charge is 51.1 gr of N140.
  
• For the 9.3x57, it also lists one recipe using the same bullet and powder, with a maximum charge of 50.9 gr.
  

PM me if you want scanned copies of those pages.
Jeff

I gave him those pages. He only wants to use a 286.