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350 Rigby Mag. or 35 Newton?

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19 April 2003, 14:20
Strawboss
350 Rigby Mag. or 35 Newton?
I'm looking for a beltless magnum round ballistically similar to the 358 Norma Mag., and wonder if any of you have experience with either of these rounds? While both of these cartridges are obsolete, handloading propositions, Bertram makes 350 Rigby brass ($310/100) and 35 Newton brass can be formed from 8x68s brass ($70/100). Case head dimensions are .518 and .525, respectively, so should easily fit a .300 mag. boltface with some work. I want to use 250gr to 310gr bullets and wonder if 1-in-12 twist should be adequate? The 350 Rigby Mag would be a great old round to own, but the Newton has the benefit of less expensive brass. Does anyone have one of these and can you tell me how much water each case holds? Paul H are you still shooting your 350 Rigby Mag. rimless?
19 April 2003, 18:34
Bwana-be
Have you considered a wildcat?
The short Jeffery would be just a wee bigger than the Norma, and I think Howell already did it. If not, it'd be easy to make up from the Dakota 338/375 specs.
I've heard there's about 4% increase going from belted case to Jeffery. Not a whole lot to worry about (if worrying about too much more powder is the sort of thing you might do!)

I've never owned a .35 but I do like the looks of a swift 300 grainer on paper, and wish more folks would try them out for me!

Bwana-be
20 April 2003, 03:59
Shadow
StrawBoss,

Have you considered the 350 G&H (as in Griffin & Howe)? It is the 375 H&H Necked down to .35 caliber with no other changes. Real easy to get brass.

Regards,

Bob
20 April 2003, 04:44
snowman
Strawboss If you want a beltless case why not the 8x68 case and neck it up to 358? Or you could go with the improved version. 8x68 brass is not hard to get.
20 April 2003, 08:14
Strawboss
Bwana be
20 April 2003, 08:44
Strawboss
Bwana be & Shadow- Yes, I considered the 350 G&H as well as the 358 Norma. Those are all good suggestions. I really want to build it on a rimless case, but in reality, the 358 Norma is probably the most practical chambering. This project started out with the goal of building a medium bore to match my custom 416 Rigby. At the time, I planned to build a 350 Rigby Magnum. Then I found out how expensive the Bertram brass is here in the USA and started thinking about other options. I rejected the idea of turning down belts and recutting extractor grooves to make brass for a new gun. Rereading some of the press on the 358 cartridges, I noted that the 35 Newton was about optimal capacity for this bore (according to Ken Waters), case length is about 2.5", and like the 416 Rigby was a modern design way ahead of the times. I believe all the 8x68s case needs is to shorten, neck up, and fire form, so it's a viable alternative for a 35 Newton and I feel the need for the extra case capacity. Both the 350 Rigby Mag and the 35 Newton are fine old rimless cartridges that meet the design criteria although are obsolete and impractical. I like a challenge.
There are several good bullets available in the 250-310gr range now that would make a good medium bore for Africa or Alaska and it's not a 375 H&H (just to be different)or 358 STA.
20 April 2003, 08:48
Strawboss
[QUOTE]Originally posted by Strawboss:
20 April 2003, 08:49
Strawboss
quote:
Originally posted by Strawboss:
Bwana be & Shadow- Yes, I considered the 350 G&H as well as the 358 Norma. Those are all good suggestions. I really want to build it on a rimless case, but in reality, the 358 Norma is probably the most practical chambering. This project started out with the goal of building a medium bore to match my custom 416 Rigby. At the time, I planned to build a 350 Rigby Magnum. Then I found out how expensive the Bertram brass is here in the USA and started thinking about other options. I rejected the idea of turning down belts and recutting extractor grooves to make brass for a new gun. Rereading some of the press on the 358 cartridges, I noted that the 35 Newton was about optimal capacity for this bore (according to Ken Waters), case length is about 2.5", and like the 416 Rigby was a modern design way ahead of the times. I believe all the 8x68s case needs is to shorten, neck up, and fire form, so it's a viable alternative for a 35 Newton and I don't feel the need for the extra case capacity of the full lenght 358/8x68s. Both the 350 Rigby Mag and the 35 Newton are fine old rimless cartridges that meet the design criteria although are obsolete and impractical. I like a challenge.
There are several good bullets available in the 250-310gr range now that would make a good medium bore for Africa or Alaska and it's not a 375 H&H (just to be different)or 358 STA.

22 April 2003, 04:27
snowman
Strawboss If you don't think you need the capacity of the full length 8x68 case what you seem to be describing is the 9.3x64. There is only .008" between the .358 & .366 of the 9.3. You want something different? I can almost guarantee you will not run into anyone else carrying the same calibre when you are out hunting. Different yet still availible as a factory round with adequate components for reloading.
22 April 2003, 05:21
dan belisle
Check out a 360 Imperial Canadian Magnum. Full length 404 Jeffrey case, improved, necked for 358 bullets. There's still a 'smith in BC that builds them. - Dan
22 April 2003, 05:24
Paul H
After having formed ~100 375 H&H cases to 350 Rigby, I can highly recomend against the process, especially since you can go through all the work, and still not get the shoulder set back far enough to fit in the chamber [Frown] The best solution for brass is Hornbear, better quality then Bertram, and less exspensive. I still need to order some, but have enough converted H&H brass for now.

If you want a match to the 416 rigby though, it is an outstanding choice. You really do need a magnum length action though, and are advised to start with an -06 bolt head, and have the bolt and extractor opened up.

If I had to do it over again, I'd likely build a 358 Norma, but I'm glad to have gotten a good deal on a set of dies, and the loan of a reamer to make the 350 Rigby. It is an outstanding round, feeds and extracts very slick, and has enough capacity to easily drive 250's 2700 fps. If I was building a rifle for the heavier bullets, I'd use a 1-12" twist, but 1-14" will suffice for most bullets, and be a bit friendlier for cast bullets.
22 April 2003, 06:52
Strawboss
Paul H, thanks for your information. I've always thought the 358 Norma was an excellent cartridge and may build one. Did you ever measure the 350 Rigby's case capacity in grains of water?
Snowman, the 9.3 seems to do everything I want and has the right bullet weights, so it's a strong contender, especially with CZ chambering their excellent 550 in 9.3x62.
22 April 2003, 13:11
Paul H
Capacity is essentially the same as the norma, I believe the Rigby holds one or two more grains, but that is identicle in my book.

If you can build the Rigby for the same price as a Norma mag, then I'd go with the Rigby, but, I wouldn't build a Rigby if it required a premium for a reamer and dies, and not to mention brass.

I think if a group order could be worked out with Hornbear, then brass price could be dropped down to about $1 a case, if we could order 500 cases. I checked Huntington's, and they don't list the 350 Rigby under Hornbear. I'm sure the sales of the Bertram 350 isn't that great, so they probably aren't that anxious about getting another manufacturer of the same brass.
22 April 2003, 16:41
JerryM
John Taylor in his book African Rifles and Cartridges speaks highly of the 350 Rigby Magnum. However, it is essentially a .35 Whelan in its factory offerings at the time of Taylor's writings. He listed the load of 225 gr bullet at 2600 fps. That can be exceeded in the Whelan, or in a .338-06.

I suppose it was loaded to a low pressure level compared to our loadings today.

Are you wanting something more powerful than the .35 Whelan? If so, then based on the ease of obtaining cases, a .35 on a belted case is the most practical. I recognize that practicality isn't the driving force sometimes in these things.

Jerry
23 April 2003, 03:25
Strawboss
Jerry, I suppose Rigby designed a big case to keep pressures low for the tropical climates of Africa and India where this round would be used. I believe this round requires a long action (375 H&H size) and with modern powders could be loaded hotter. I considered the 35 Whelen and all the Ackley Improved variants and the 9.3x62, but don't believe the Whelen can propel the heaviest bullets to adequate velocity. I'm leaning towards the 35 Newton as a cheaper option that would work in a standard length action to make a trimmer lighter package. Paul & Jerry, thanks for your input.
23 April 2003, 10:53
Paul H
I haven't tried the 310 gr woodleighs, yet [Big Grin] but I believe the 350 Rigby ought to be capable of ~2400 fps from a 24" barrel. This would certainly outdistance the 35 whelen by a large margin.

It indeed requires a magnum length action, the case is 2.76" long. Many -06 actions could be opened up, and my rifle is built on a VZ-24, for all the lengthening of the feeding slot in the front. I wouldn't be comfortable opening up the action any more in the front, but it does work for this length round.

I think the 358 Norma is the most practicle, and for plenty of capacity in a mag length action, the 358 STA is a fine round.
23 April 2003, 14:51
Strawboss
Paul, excellent advice. I see you've got lots of practical experience with the Rigby case. I agree the 358 Norma is the most practical, but I'm going to investicate the cost of the 35 Newton in brass & dies. The 35 Newton is essentially a beltless 358 Norma as the lengths are similar, shoulders about the same length although of slightly different diameters, and the Newton could be built on a standard action. I would go with at least a 24" barrel which I prefer on my hunting guns. Do any of our members have a 35 Newton or load for one?
23 April 2003, 16:43
RCHAPURA
The 1 in 12 twist will stabelise every thing that you want to shoot in it . My Norma shoots 225 to 275 excellently . I have been considering the 310 to play with . A newton sounds fun as well .
25 April 2003, 15:32
woofer
why doesn't anyone neck the dakota up from 338 for a short or down from 375 for a long? is it duplicaated from another wildcat? i dont have all the 35 rounds memorized so i am not sure someone hasn't brought it up.
thanks
woofer
02 June 2003, 14:04
<gattman>
Strawboss, I have had a 358 beltless magnum built on the 9.3x64 Brenneke case. Capacity is the same as 358 Norma. I simply neck down to 358 using a 38 Super die set. No other case changes are made. A standard length action is easily converted simply by opening up the bolt face. My rifle has just been completed and the scope is being mounted. I am in the process of moving so I won't be able to get to the riflesmith to pick it up for a couple more weeks. In the meantime I'll be working up some loads. I plan to start with light 358 Norma load data. If you haven't started your project yet I'll report on ballistics and accuracy as soon as I can get to the range. (probably about 3 weeks).

gattman
03 June 2003, 07:41
Strawboss
Gattman, I'm in no hurry and am having lots of fun researching the different 358 cartridges. There is a group of well-informed hunters that seem to prefer this bullet diameter. Commercial loading of the 35 Whelen created the demand for more and better bullets, and there is now a good selection. I look forward to your report when you shoot your new gun.
07 June 2003, 19:24
Frank Martinez
according to "handloaders manual of Cartridge Conversions" by John Donenelly, the following capacities are available:
350 Rigby Magnum 91.25 Gr. water
358 Norma 87.57 Gr.
8x68 (S) Magnum 86.54 Gr
9,3x64 Brenneke 87.04 Gr.
35 Newton 92.56 Gr. (Described- turned from 375 case.
35 Whelan improved 73.58 Gr.
358 Barnes Supreme 100.90 Gr. From 300 H H case

If you choose to go with a rimmed case there is always the 360 #2 Nitro Express @113 Gr.
What fun.
Frank
08 June 2003, 13:31
Strawboss
Frank, thanks for the info. I made the mistake of loaning out my copy and it never came back. That tells me what I needed to know. The Newton has about 5 grs. on the Norma and more than the Rigby without having to go to the magnum length action. I would bet the 35 Newton on the 8x68s case might do a little better.
08 June 2003, 15:17
Frank Martinez
I know what you mean about loans. I loaned an autographed copy and never saw the book or the fellow I loaned it to again. I guess it is true what they say- Never a lender or borrower be?
Keep us posted on your progress.
Frank

[ 06-08-2003, 06:18: Message edited by: Frank Martinez ]