375 ruger necked down to 358

375 Ruger case capacity is 99gr H2O.

300/340/375 weatherby all basically have the same capacity as the 375 Ruger. All between 98-100gr H20.
Wouldnt be gaining anything there...

Now if you used the 378 weatherby, that would be a significant increase in case capacity. But then a person would need a Lapua size action for the .580 case rim diameter

You could set the bullets further out to gain case capacity.

I have to agree with John. With the .338 Campfire (which is a .338-375 Ruger improved), you can use the heavier and longer bullets. The .340 Wby is a GREAT round, but I nearly duplicated it in an over-loaded .338 Win Mag experiment. The Bee has all that case length, and the belt eating powder space.

I'm not a belt hater, I love belted cartridges all the way down to the .224 Wby :D
 
I also still own a 338-375 Ruger. It pushes 250gr Berger Elite hunter bullets at 2980 fps in a 26" barrel. That's quite a bit faster than 338 Lapua factory ammo offerings with 250gr bullets.

It puzzles me (and delights me) how it out-performs the .338 RUM, even though the RUM still has the .550". Is the shoulder steeper than the RUM ? I would like to have a .338-375R with something like a 32.5° shoulder. Steep seems to work for the Creed.
 
I want to see if a .458 is possible. But with no belt, how would you headspace it?

Yes, a 458 Ruger would work just fine. (Someone on AccurateReloading has done this.)
The outside neck diameter would be .488" and the shoulder would be between .512" to .518" depending on how much case-body taper you would want. The resulting .024" to .030" shoulder would work fine and is more than the .018" of the 400Whelen. From the base to the shoulder you could use about 2.09" in order to have a caliber length neck.
 
35-375 Ruger would be about the same as the 35 Nosler (Nosler has the 35 Nosler approved as a standard cartridge but has not made any rifles, brass or ammo for it), they both would be about the same as the old 35 Newton, witch was a very good cartridge, just way ahead of it's time like all Newton rounds. From the new loading data I'm seeing the 35 Whelen with new powders matches 358 Norma loads. The loads for the 358 Norma Mag. do not seam to have ben up dated for a long time, I would love to see how it would preform with new powders. The 358 STA is a grate cartridge and a heavy hitter. It is very tempting for me to build a 358 STA.
 
35-375 Ruger would be about the same as the 35 Nosler (Nosler has the 35 Nosler approved as a standard cartridge but has not made any rifles, brass or ammo for it), they both would be about the same as the old 35 Newton, witch was a very good cartridge, just way ahead of it's time like all Newton rounds. From the new loading data I'm seeing the 35 Whelen with new powders matches 358 Norma loads. The loads for the 358 Norma Mag. do not seam to have ben up dated for a long time, I would love to see how it would preform with new powders. The 358 STA is a grate cartridge and a heavy hitter. It is very tempting for me to build a 358 STA.

It's my Understanding a .300 Norma, .338 Norma, and .358 Norma are all loosely based on the .416 Rigby, just a little shorter. The .308 Norma from the 60's is the only odd man out, correct?
 
It puzzles me (and delights me) how it out-performs the .338 RUM, even though the RUM still has the .550". Is the shoulder steeper than the RUM ? I would like to have a .338-375R with something like a 32.5° shoulder. Steep seems to work for the Creed.

My chamber is just a straight 375 Ruger necked down to 338. No other modifications.

Not sure how or IF it outperforms the RUM. I've never owned a 338 RUM.

My barrel is a Brux, 1 in 10" twist with Sendero contour finished at 26". I have pushed the 250gr up over 3000 fps, but Hornady brass primer pockets will not hold up. They seem to do fine just below 3000.

I was using 76.5 gr of H4350 for my original load and was getting 2930 fps. Changed to RL16 when it hit the market for better case fill. Accuracy was still good with RL16 while using the same exact charge weight of 76.5gr, but speed jumped to 2980 fps average. No pressure signs and primer pockets staying strong.

Here's a short 4 round ladder test I did at 100 yards checking POI shift with RL16 using weights of 76.3gr to 76.9gr. Good temp stable powder and not much POI shift. Speeds have been verified on 3 different chronographs over the years.

20181210_064156.jpg
 
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It's my Understanding a .300 Norma, .338 Norma, and .358 Norma are all loosely based on the .416 Rigby, just a little shorter. The .308 Norma from the 60's is the only odd man out, correct?

No. The 358 Norma Mag is the same as the 308 Norma Mag. Both belted mag cases with .532" rim.

The 338 Norma Mag and 300 Norma Mag are on the 416 Rigby case. The 338 Norma was designed first and made from the 416 Rigby. The 300 Norma came along next and is a necked down 338 Norma.

The 358 Norma Mag case is just a hair longer than a 338 Win Mag case. With only .020" longer case and .020" wider neck, its hard to tell the 358 Norma apart from the 338 Win Mag at first glance without looking at the headstamp.

The Norma case names are starting to get confusing nowadays. I hope they start coming up with new names before all of our heads start spinning! Lol
 
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morning, I hand load my 340wbee accu-mark.
none better. with the right bullets, BARNES
lots of meat in the freezer. justme gbot tum
 
It's my Understanding a .300 Norma, .338 Norma, and .358 Norma are all loosely based on the .416 Rigby, just a little shorter. The .308 Norma from the 60's is the only odd man out, correct?
Drilldog got you answered before I got to it, but that's OK, he is right.
I all so think we are getting too many cartridges in the same calibers that duplicate and over lap so much it's crazy and mind blowing. Most people don't even know of more than a small fraction of them. It is fun for us gun guys but at the same time I have to look at some of them and say "why" it's the same as this, this and this......
Each to his own and it do give us a lot of cartridges to have a lot of fun with.
 
Drilldog got you answered before I got to it, but that's OK, he is right.
I all so think we are getting too many cartridges in the same calibers that duplicate and over lap so much it's crazy and mind blowing. Most people don't even know of more than a small fraction of them. It is fun for us gun guys but at the same time I have to look at some of them and say "why" it's the same as this, this and this......
Each to his own and it do give us a lot of cartridges to have a lot of fun with.
I agree, the .30 caliber field could be simplified, and broken down in three options.
Standard Power - .308 Winchester
High Power - .300 Winchester Mag
X-Tra High Power - .300 Rem Ultra Mag

The .33's
.338 Federal
.338 Win Mag
.338 Lapua

.284"
7mm-08
7mm RM
7mm STW

.277"
Blahh, no one cares anyway lol

.264
.260 Rem
.264 WM
6.5-300 WBY

That's my opinion any way lol
 
Nice thing about the Ruger (aka; PRC), Nosler, and Norma Mag(416 Rigby based) cases is that they are significantly shorter than the Weatherby, Lapua or other large belted magnum cases, yet provide very similar case capacity or sometimes even more capacity. This allows for the use of modern heavy-for-caliber long range VLD bullets in a standard long action magazine without having to seat the bullets so deep you eat up 20% of the case capacity. Being able to seat the bullets out farther also keeps the bullet bearing surface out of the donut area of the neck.
 
I agree, the .30 caliber field could be simplified, and broken down in three options.
Standard Power - .308 Winchester
High Power - .300 Winchester Mag
X-Tra High Power - .300 Rem Ultra Mag

The .33's
.338 Federal
.338 Win Mag
.338 Lapua

.284"
7mm-08
7mm RM
7mm STW

.277"
Blahh, no one cares anyway lol

.264
.260 Rem
.264 WM
6.5-300 WBY

That's my opinion any way lol
.270 Win., .270 WSM and .270 WBY
 

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