I am working up a load for my 9,3x74R Tikka 512.
The bullet is a 320grs. Woodleigh sn rn. My aim is to take it to an MV of 2373 FPS and there by reaching an even 4000 ft/lb, as I intend to use it on buffalo.
There is no data available from any manual since the bullet originally is meant for the 360#2 cal.
I asked for advice,on where to begin, in this forum and got it. So far I have reached an MV of 2000FPS with no visible pressure signs, I need another good 300 fps to reach my goal.
I use N140 since that is the powder used for this cal. with the heaviest bullet (published in Viht. loadman. #3)
N540 is supposed to be exchangeable with N140. But with slightly higher Mv's, so using this powder may help in my "quest".
My question is: Does anyone have any expierience with this, they would like to share?
Input on the matter of powder choice for this cartridge combination is also welcomed.

Thanks in advance
Niels

I have done this a couple of times a slower powder is safe to use with a faster powders loading data but start with min. load and wath pressure signs.vv540 is slightly slower than vv140.

I found that N540 in .308 was a great performer whereas N140 was somewhat lazy. This is not typical, and what I want to say is: have a chronograph at hand when developing a load, as powders of the same kind but different batch may perform noticably different.

Two base powders as N540 are said to cause a stronger barrel wear.

My gunsmith is also of the opinion that N540 wears out barrels significantly faster than N140.

Regards

Ray

vssf, the problem is that we do not know what "significantly" means. Maybe your gunsmith has a figure like x percent longer barrel life for single bas powder - and x may be so small that the 500-series is worth using it?

The 9.3x74r earned it's reputation with standard jacketed 286gr bullets at about 2,200-2,250 fps. Throw in todays bonded bullets and performance should be even better.

I think you have no chance at all of obtaining 4kft lbs with a 9.3x74r and certainly not with the 320gr. ME=M/2xVsquared so M brings very little to the energy party whereas V brings himself squared and as V is a big number V rules in energy BUT most would have us believe that ME alone is nothing.

I'm not sure the 320gr bullet is a good idea in this round, I would have thought that the 286br partition was made for the 9.3x74r. When I did terminal performance tests on them at 9,3x74r velocities the performance was phenomenal and they ended up looking perfect adverts for buffalo bullets! The partition is far forward so weight retention is excellent and yet expansion is good at the lowest velocities.

Niels,according to Quickload your goal with the 9.3 x 74 R is impossible within the pressure limits of the caliber,even with N560,so I sugest to go for another bullet,less heavy.

Hugh.

Hi Hugh and 1894
You are most certainly right about not reaching 4000 ft/lb. Not with any bullet in that caliber, within pressure limits. I see that now, from your advice and from the progress i my chronographed loads. it's still fun though.
the 320 grs. bullet was chosen because of it's immense s.d. value. (it will expand and do it's job within the MV already reached)
The goal of 4000 ft/lb is a set minimum for a cartridge used for buff. in most african countries. So I want to see how close I can get.
The 286grs. woodleighbullet is good for Moose (or any other bonded bullet)
The Nosler i am not so sure about... It certainly will do its job, BUT Since it expands so well and easily it will also expand if a little brush is hit before it reaches its target, and we do have a good deal of so called "bajonet posts" where i hunt moose.

For the buff I will probably have to either hunt them in a country that allows 9,3X74R, or buy a bigger one. But what do I need a bigger gun for afterwards.....?? Giant moose..!!?? Or maybe go again

a thing that puzzels me is that there seemingly is'nt any published loaddata on the caliber using slower powders than n140 and Norma 202. I am brought up to believe that a slower powder for a heavier bullet is for the better... but n140 and similar powders are about the slowest I have found and they are used for allmost any bullet weight.

I would consider the Swift A frame 300 grs. For solids I would look for a premium: Woodleigh, GS Gerald Shultz, Trophy Bonded Sledgehammer???

Ditto on the NP 286 grs. Seems the partition is well forward, looks like a great big game bullet.

Hermann

I think Atkinson posted that he thought the 286gr partition was a fantastic compromise and from what I saw I would concur.