thoughts on a 366-375 ruger

[Shawnba67]

I am consider playing with this simple neck down wildcat on a Win 70 rifle. I had bought a 9.3mm barrel with he plans to build a 9.3x62 but then i thought i need a magnum in the stable.
Anyhow what are some shortcomings I might not be forseeing?
I intend to attempt to alter a $30 set of 375 ruger dies on my lathe to accept neck bushings.
Im expecting to perform within 5% of a 375 ruger?
Is this a realistic expectation?

 

[watercam]

I love the 9.3s and think it is a great idea! Just make sure you ship ammo to where ever you are hunting ahead of time! Assuming that you are staying with 250 and 286 gr. bullets you should beat or match the parent cartridge velocity.
Personally I use the Barnes TTSX 250 bullets to keep some velocity while still maintaining maximum penetration.

 

[Ledd Slinger]

I would just get a custom set of dies made. Gonna be tough to ream out a hardened sizing die...

I have a 338-375 Ruger. It is a very efficient and powerful case design. I push the 250gr 338 bullets over 100 fps faster than 338 Lapua factory ammo offerings, yet I'm using 15-20gr less powder in my hand loads (getting 2952 fps in a 26" barrel just under max pressure)

With the 375R necked down to 9.3, the 9.3x62 and the 9.3 Brenneke would pale in a comparison of performance.

There are no shortcomings in the 375 Ruger case design. Only problem is that you are limited to only Hornady brass. It's not the worst, but not near the best either. Tho with good case prep, Hornady brass will bring very good accuracy. I get good primer pocket life with the Hornady brass so that's definitely a good thing to say about it.

 

[Kurz]

I am consider playing with this simple neck down wildcat on a Win 70 rifle. I had bought a 9.3mm barrel with he plans to build a 9.3x62 but then i thought i need a magnum in the stable.
Anyhow what are some shortcomings I might not be forseeing?

I have always appreciated the 9.3 caliber in many cartridges, factory or wildcat. I've managed to wildcat several versions, some valuable while others simply fell by the wayside. But all were fun and good learning experiences if nothing more. I have built many 9.3x64 Brenneke rifles which I supply RWS brass with for handloading. The quality of the brass makes a difference when it comes to running near the top of the pressure range. The difference is the bolt face (.496") as compared to the more standard (.532") bolt face of the Ruger. But I can cut the bolt face any way I wish so it doesn't inhibit me.

I don't think the term 'shortcomings' really comes to bear on this project but I do think you need to examine your reamer specification before jumping into the fray. While the case is essentially a long action case, Ruger set it up to work with the 3.340 OAL. The longer bullets, such as the TTSX will perform better when the reamer allows for an OAL of 3.600 inches.

I intend to attempt to alter a $30 set of 375 ruger dies on my lathe to accept neck bushings.

I don't use a (chucking) reamer to modify any of my dies, I use brazed carbide boring bars. They are a tad less expensive than the solid carbide boring bars and I find the performance to be equal. The majority of the dies I've modified have not been hard enough to stop me from making precise cuts successfully. Measure twice, cut once.

Im expecting to perform within 5% of a 375 ruger?
Is this a realistic expectation?

That will be determined by your reamer design and the load you establish as your accuracy load. Some folks stop way shy of any of the upper performance loads for some reason. Others of us like to have the upper nodes.

Here is some information about the factory loads for the .375 Ruger:

"Hornady loads their 250gr GMX, 270gr SP-RP, and 300gr DGX/DGS bullets to advertised velocities of 2,900fps, 2,840fps, and 2,660fps respectively (using a 24″ barrel). DoubleTap currently offers loads with 260gr Nosler Accubond along with 235gr and 270gr Barnes TSX bullets with advertised loads of 2,900fps, 3,100fps, and 2,825fps respectively (using a 23″ barrel)."

Good Luck with your project!

 

[MClark]

For hunting I would have concerns with the bullets. Those available are for X62 and X72R velocity. The TSX and Partition would be ok at close range but those of conventional construction may come apart.

M

 

[Kurz]

For hunting I would have concerns with the bullets. Those available are for X62 and X72R velocity.

We've been shooting the very same bullets for hunting for all the years that the 9.3x64 cases have been available. At 2950 - 3000 fps. each and every bullet performs as advertised by the manufacturer. The limit is not just the case capacity but the length of the barrel as well. You will not gain that much more by using a larger case (.375 Ruger), especially if you keep the barrel length to 26" or less. I tested the 9.3x338 Norma Mag. with these vary same hunting bullets and still couldn't manage more than a little over 3000 fps. because of the barrel length. You will run out of powder space or barrel length before you achieve any appreciable gain in velocity which will create a problem with bullet construction.

Regards.

 

[Ledd Slinger]

We've been shooting the very same bullets for hunting for all the years that the 9.3x64 cases have been available. At 2950 - 3000 fps. each and every bullet performs as advertised by the manufacturer. The limit is not just the case capacity but the length of the barrel as well. You will not gain that much more by using a larger case (.375 Ruger), especially if you keep the barrel length to 26" or less. I tested the 9.3x338 Norma Mag. with these vary same hunting bullets and still couldn't manage more than a little over 3000 fps. because of the barrel length. You will run out of powder space or barrel length before you achieve any appreciable gain in velocity which will create a problem with bullet construction.

Regards.

Disagree. You probably weren't testing powders with the correct burn rate. I would bet a lot of money that the 9.3-375R would smash any speeds possible with the Brenneke provided the correct powders were used. The 338 Lapua likes really slow powders with heavy bullets, as you increase the bore diameter, generally the faster burning powders start to give better speeds on any given bullet. If you continued to use the same burn rates the 338 Lapua prefers, then it's easy to see why you didn't notice much gain

 

[Kurz]

Disagreement is the basis of good discussion. If we all agreed then there would be no reason for these discussion to exist.

Disagree. You probably weren't testing powders with the correct burn rate.

Then you would be wrong since this is a part of every test I run on every cartridge and bullet combination. It's part of the business. I actually shoot these tests as opposed to just surmising what the outcome might be. I have notebooks full of data from original tests through updated tests using new powders.

I would bet a lot of money that the 9.3-375R would smash any speeds possible with the Brenneke provided the correct powders were used.

Start writing the check because you would be wrong again. Yes, there is an 11 grain difference between the two cases but that difference doesn't necessarily provide for any significant increase when the barrel length is then the deciding factor. This is based on standard pressures with not to exceed SAAMI levels in place and the efficiency of the loads. I see no benefit to using loads which fall under a 95% fill. Note the use of the term 'significant'. I don't consider 50-100 ft./sec. to be either 'smashing' nor significant. And the difference BY TEST is generally about 50 ft./sec. from a 26" barrel. This significance is also predicated on the fact that barrels routinely gain or lose velocity based on when they are tested in their life span. I have seen dozens of cut rifled barrels start out 100-200 ft./sec/ slower than after they have fired 200 shots and gained velocity. Ask Frank at Bartlein.

as you increase the bore diameter, generally the faster burning powders start to give better speeds on any given bullet.

Usually true. I've been teaching this in my advanced ballistics class for better than 25 years.

Regards.

 

[Ledd Slinger]

It would be an interesting cartridge to test for sure. When you bring 'over 95% case fill' into the picture you change things. This means you are probably using fairly slow burn rates. Granted I do try to keep case fill high as well, but I've had a handful of rifles that shot better with faster powders and less case fill. The results show up on the paper and I refuse to limit myself to a 'rule of thumb'.

When I can push a 250gr bullet at an average speed of 2952 fps from a 26" barrel in a 338-375 Ruger, I don't see why the same case with a larger bore wouldn't show equal excellent performance. Would you like to hazard a guess on the powder I'm using on this big 338 cartridge? (Also consistent 1/2 MOA accuracy)

 

[RULOJOE]

It would be an interesting cartridge to test for sure. When you bring 'over 95% case fill' into the picture you change things. This means you are probably using fairly slow burn rates. Granted I do try to keep case fill high as well, but I've had a handful of rifles that shot better with faster powders and less case fill. The results show up on the paper and I refuse to limit myself to a 'rule of thumb'.

When I can push a 250gr bullet at an average speed of 2952 fps from a 26" barrel in a 338-375 Ruger, I don't see why the same case with a larger bore wouldn't show equal excellent performance. Would you like to hazard a guess on the powder I'm using on this big 338 cartridge? (Also consistent 1/2 MOA accuracy)

Yes Ledd, i Would love to see your Recipe, powder , Bullet etc.. I'm not sure what to Load for my set up .. it's a 378 weatherby case improved ( double radius taken out ) 40 degree Shoulder ? necked down to .366 . it's called a .366 Rizzoni magnum... i don't want to lose what it was intended for . I want a long range Moose Cartridge , so i want the speed and Trajectory, it was designed for so i dont want to use slow powder and huge heavy bullets.. i want a Boattail that will expand at 650 yards and not pencil punch them . I bought some nosler Ballistic tip .366 - 250 #36250 grainers at a gun show, i didnt know how they were Constructed at the time .THEY WERE NOSLER HUNTING Bullets so i figured I'd take a chance.. ( partitions are BA so !! ) Heavy weight so up close may work enen though not Bonded ., softer jacket may actually exand properly at 600 y but is it a tough enough Bullet.. .?? I got the hornady gmx 250 #3562 FB not BT . Like the interloc 286's const wise , but i want a lighter 235 to 250 weight Boatail . I think i have a 26 inch barrel braked 28" barnes solid copper may be too tuff . I can't see spending $150 for 100 Bullets of Whatever . Looking hard for components ! Oh my 30- 378 needs a good bullet too . Love's the 208 Hornady eld match's but simple cup and lead aint going to cut it for hunting. For WT deer they maybe ok but not for Elk etc Thoughts ? Rulojoe@gmail.com 785-633-6698 joseph Simmonds on Facebook .. message me please ! Thank you Joe .

 

[RULOJOE]

It would be an interesting cartridge to test for sure. When you bring 'over 95% case fill' into the picture you change things. This means you are probably using fairly slow burn rates. Granted I do try to keep case fill high as well, but I've had a handful of rifles that shot better with faster powders and less case fill. The results show up on the paper and I refuse to limit myself to a 'rule of thumb'.

When I can push a 250gr bullet at an average speed of 2952 fps from a 26" barrel in a 338-375 Ruger, I don't see why the same case with a larger bore wouldn't show equal excellent performance. Would you like to hazard a guess on the powder I'm using on this big 338 cartridge? (Also consistent 1/2 MOA accuracy)

 

[JSH]

November 3 2017 was the last post for n this before the dust and cobwebs got knocked off.
You may well be better off to do a PM or direct contact to the person you seek.

 

[Ledd Slinger]

Yes Ledd, i Would love to see your Recipe, powder , Bullet etc.. I'm not sure what to Load for my set up .. it's a 378 weatherby case improved ( double radius taken out ) 40 degree Shoulder ? necked down to .366 . it's called a .366 Rizzoni magnum... i don't want to lose what it was intended for . I want a long range Moose Cartridge , so i want the speed and Trajectory, it was designed for so i dont want to use slow powder and huge heavy bullets.. i want a Boattail that will expand at 650 yards and not pencil punch them . I bought some nosler Ballistic tip .366 - 250 #36250 grainers at a gun show, i didnt know how they were Constructed at the time .THEY WERE NOSLER HUNTING Bullets so i figured I'd take a chance.. ( partitions are BA so !! ) Heavy weight so up close may work enen though not Bonded ., softer jacket may actually exand properly at 600 y but is it a tough enough Bullet.. .?? I got the hornady gmx 250 #3562 FB not BT . Like the interloc 286's const wise , but i want a lighter 235 to 250 weight Boatail . I think i have a 26 inch barrel braked 28" barnes solid copper may be too tuff . I can't see spending $150 for 100 Bullets of Whatever . Looking hard for components ! Oh my 30- 378 needs a good bullet too . Love's the 208 Hornady eld match's but simple cup and lead aint going to cut it for hunting. For WT deer they maybe ok but not for Elk etc Thoughts ? Rulojoe@gmail.com 785-633-6698 joseph Simmonds on Facebook .. message me please ! Thank you Joe .

I’ve come to the conclusion that I won’t build a rifle in a caliber that Berger doesn’t make bullets for. So I only shoot up to 338 cal. I’ve never had a single Berger bullet fails me on countless kills in the last 16 years in 6.5, 308, and 338 cal so I might as we stick with what works. Then add in the good price per bullet and the best long range hunting accuracy and it’s a no brainer for me.

 

[wwbrown]

I don't hunt with Bergers but one big difference between my Ruger 375 and my 9.3 x 62 is bullet selection, there are a lot more 375 bullets out there. Yes, the 9.3 does not quite have as much energy as the Ruger but black bears don't know the difference and the recoil is quite pleasant.

 

[Ledd Slinger]

A good additional piece of information for this thread (now almost 5 years later) is that ADG and Lapua both are making 300 PRC brass which of course based on the 375 Ruger case. When building any wildcat based on the 375 Ruger case, it’s best to use ADG or Lapua.

I was never able to push the top end of speed in my 338-375R using Hornady brass. I switched to ADG 300 PRC brass, necked it up to 338 cal and what a difference it made! Not only in being able to handle pressures of max loads, but my accuracy is considerably better as well