Question about the low pressure of 9.3x62

elker

CGN Regular
Rating - 100%
11   0   0
this caliber has very low pressure at a little above 56,000psi. Far lower than 62,000 of .308 or 65,000 of 375 rum. I'm thinking of putting more powder (gradually like what c-fbmi did to his 9.3x300wm) into high quality brass like the Lapua brass from hirsh precision. Will that bring out the best of .366 Wagner?
56,000 is the pressure from 100 years ago,right?
 
Last edited:
What the hell do you expect to gain by doing this? The 9.3x62 is a fantastic cartridge, and will kill anything that walks, with accurate shot placement.
I agree. But,we can also make 375 rum safer by lowing it to 56,000psi and it will still kill anything moving in North America.
Why waste the huge potential of an excellent cartridge if we can safely upgrade it?
 
Bob has run 286 partitions at over 2600 fps out of his 22" tikka 9.3 x62 using reloader 17 as he states and provides a picture of the chronograph on his blog. He's been around long enough to know if the recipe is safe in his own particular rifle and if you read the blog he calculates the difference between the 9.3x64 and the 9.3x62 velocity with the same projectile and COAL at 40 fps loaded to the same pressure.
It works for him,
I use about 4 grains less of the same propellant than Bob in different cases and easily exceed 2500 fps with my 23.5" barreled x62 and the 286 partition with its .405 bc making it an honest 300 + yard rifle with absolutely no more case head expansion or pressure indication than the same bullet running 2400 with RL 15, actually its probably less and brass lasts forever with primer pockets remaining tight.
Each to their own and I'm not advocating anyone do the same.

Oh it shoots damn well to boot with three usually under an inch @ 100
 
56,000 is the pressure from 100 years ago,right?

No, the pressure was raised by the 1930's, from a velocity of 2150 fps for a 285 grainer to 2400 fps (RWS) and it's still the same MAP (3900 bar) listed by CIP today .
Just as a sidenote, the pressure rise is the square of the velocity increase difference (say 20% velocity increase = 40% pressure increase) for a given powder / primer / bullet combination.
 
What would be the reason to increase the pressure? 9.3x62 does not fly far, it drops around 47 inches on 400 meters. 300 Win Mag, 338Win Mag or 6.5x55 sweede will drop 22 or so. Adding 10% of pressure won't change a thing even at 400 meters, not to mention long range. The 9.3mm chunk of lead won't fly anyway. Yet inside the 200 yards 9.3x62 has enough power to drop anything alive. Why bother?
 
^^^ Are you sure about the 47 inch drop at 400 meters? I'd like to know what bullet with what b.c. we're talking about. I don't expect it to run with the 2 magnum cartridges, or a swede, but surely that can't be right.
 
What would be the reason to increase the pressure? 9.3x62 does not fly far, it drops around 47 inches on 400 meters. 300 Win Mag, 338Win Mag or 6.5x55 sweede will drop 22 or so. Adding 10% of pressure won't change a thing even at 400 meters, not to mention long range. The 9.3mm chunk of lead won't fly anyway. Yet inside the 200 yards 9.3x62 has enough power to drop anything alive. Why bother?

Why do we drive vehicles with variable valve and ignition timing , fuel injection and disc brakes use transistors and fluorescent lights when those good old magneto's, points, drum brakes etc worked so well and it doesn't do anything the old stuff wouldn't do.
There has been just the odd improvement in powders, primers ( imagine , they're even non corrosive now) projectiles and brass cases since 1905, me I prefer to make use of some of those improvements. I suppose you drive a model T and shoot nothing but cast bullets propelled by black powder in your trapdoor 45/70 when your not spinning wool for your clothing.

If you take the emotion and the " tradition" out of it , a modern bolt rifle in good condition doesn't really give a #### what the chamber dimensions are cut to, what the cartridge is called or how long its been in existence. Its a pressure vessel pure and simple for that minute amount of time from ignition until the bullet exits.
Why would you not use a safe higher pressure load that delivered best performance to go with the carefully selected case , primer and projectile. Especially when you've taken the time to carefully work up to it , see no signs out of the ordinary and realize real world increases in performance resulting in extended range, more energy delivered to the target and excellent accuracy.
If we didn't bother, we'd be shooting 220 grain Krag bullets out of the 30-06 @ 2200fps , corrosive primers and all.
 
Here's the data for the load I'm talking about bc is .405 for the 286 grain nosler partition, 3 inches high at 100 yds and yes thats over 4000 ft lbs at the muzzle.
VEL Energy Trajectory

Muzzle 2530 4065 -1.5
100 2320 3417 + 3
200 2119 2852 + 1
300 1930 2364 -8.8
400 1751 1947 -28

Now for the load on the hornady website

Muzzle 2360 3537 -1.5
100 2160 2963 0
200 1970 2465 -6
300 1791 2037 -20.9
400 1624 1675 -46.8

528 ft lb of energy at the muzzle of difference & 170 fps of velocity , at 300 yards which I consider to be the loads practical range the difference is 327ft lbs and 139 fps with 3.2 inches less drop at the same range with a 3 inch high 100 yard zero for both loads.
Once again, I'm not advocating anyone load to this level, I'm answering the OP's question with real world experience and data. I'm beginning to understand Gatehouse a little better and his Luddite comments.
 
Last edited:
Sure it's possible and safe. I'm not sure that there is much to gain from it though. Same can be done with cartridges like the 416 Rigby. Load that giant case full of powder and launch 400gr bullets at Weatherby or greater speeds. But why? Because it's manlier than wearing a black leather codpiece and letting some Asian gal beat you with a riding crop? If you take bullets designed for a certain velocity envelope and turn up the speed you can't act surprised when a previously stellar performer takes a giant dump right when you need it to behave the most.
 
Why do we drive vehicles with variable valve and ignition timing.

No, no, dont get me wrong. I'm all for the pushing it over the limit. It just in this particular case it looks like you are trying to mount a huge spoiler and on the trunk of a honda civic. It won't really do any good compared to anything slightly more advanced. We are talking about +10% pressure on a bullet which flies like a brick. It won't make any difference at 500 and beyond, at 200 and under no one will see the difference of extra of pressure. No?

PS
Forget the honda civic, bad metaphor. It's a heavy tractor - trusted and true to make job done at closer ranges.
 
Sure it's possible and safe. I'm not sure that there is much to gain from it though. Same can be done with cartridges like the 416 Rigby. Load that giant case full of powder and launch 400gr bullets at Weatherby or greater speeds. But why? Because it's manlier than wearing a black leather codpiece and letting some Asian gal beat you with a riding crop? If you take bullets designed for a certain velocity envelope and turn up the speed you can't act surprised when a previously stellar performer takes a giant dump right when you need it to behave the most.

I'm pretty sure the old Partition is up to the task , the last one I drove through a good sized blackie from stern to stem looks like it belongs in a magazine add even after smashing a shoulder. On the other hand the increased velocity might actually help in some cases (barnes tsx/ Hornady Gmx) in initiating expansion, like I pointed out in a previous post I'm not advocating anyone do it, only responding to the OP's question .
I use the privi 285's as well but at under 2400 fps and have had great success with them but after 2 under 100 foot encounters with our local large coastal brown fuzzers (both sows with 1 1/2 year old cubs) last year I prefer my spiffy partition load even if its all in my head .
Here's a link to some data if anyone's interested http://www.realguns.com/loads/93x62mm.htm
Must go dust off my codpiece and braid my chest hair now.
 
With a long enough throat to allow loading to the same COAL and the requisite magazine space more powder capacity is available to be used.

My point was that you can doctor up the numbers all you like, but the x62 won't match the potential performance of the x64. Not that there's anything wrong with the 9.3x62, but don't make it out to be something it's not.
 
Back
Top Bottom