30/40 Krag rolling block Question

[brstevns]

What should one keep psi in a Model #5 rolling block rebarreled to 30/40 Krag.
Does anyone have some good loads? Plan on using 311284, 311291 , 310299 and a Lee 155 for the SkS. Just looking for 1800 to 2000 fps.

[uscra112]

I know nothing about rolling blocks, except that there were 7mm varieties. One of those could be loaded to 7mm pressures, since the Krag case is slightly smaller at the base.

Then I look at data that says 7mm is loaded to 50,000 psi. Seems an awful lot for the early Mauser rifles, let alone a rolling block. But if you're shooting only cast, your pressures won't get anywhere near that. My Krag loads for cast 200 grain GC bullets are at most 30k psi.

[Rich/WIS]

IIRC the No 5 was the smokeless powder action most often found in 7mm Mauser. If this is correct it was built to take pressures somewhat in excess of the 42K psi max of the standard Krag loading. Cast loads in the range you mention are well below that range, any cast loads listed in various manuals are in the mid 30K range. Even full power jacketed loads are barely hitting 40K. If the No 5 is a BP action disregard the above.

[Adam Helmer]

Very good question. Who rebarreled the rolling block and what was the reason? Those old RBs were made over a century ago, I would be careful with any loads.

Adam

[Texas by God]

I'd start out with about 30 grains of IMR 3031. Please post pictures when you start playing with that gun I would really like to see it.

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[Der Gebirgsjager]

I know that someone on the forum has all the rolling block answers, and I'm seeking a few myself! I recently acquired what I believe to be an 1870s Argentine RB carbine in .43 Spanish. I searched the internet for quite awhile and could only find one recommended load which used 28 - 31 gr. of 4198, but didn't specify a bullet weight. I'm going to start with 370 gr., and did get one recommendation for Trail Boss from a fellow forum member, who suggested 12 - 15 gr., said that's what he uses, but that it would probably take more. If it was a .30-40 Krag chambering I think TbG's suggestion would be a good place to start, or maybe a starting load of IMR 4895. Then, there's the 12 gr. of Red Dot load that many use as a started in old military rifles. I was tempted to try that, but the cartridge case is so cavernous I think I'd do better with the bulky Trail Boss. Anyway, perhaps someone "in the know" will chime in, as I know that there are many RB collectors and shooters out there.

[brstevns]

The number 5 rolling was designed for smokeless powder, was chambered in 7mm, 8 label, 7.62x54 russian and the 30/40 Krag.
Mine was a 7mm that is beening rebarrel.

[brstevns]

I know that someone on the forum has all the rolling block answers, and I'm seeking a few myself! I recently acquired what I believe to be an 1870s Argentine RB carbine in .43 Spanish. I searched the internet for quite awhile and could only find one recommended load which used 28 - 31 gr. of 4198, but didn't specify a bullet weight. I'm going to start with 370 gr., and did get one recommendation for Trail Boss from a fellow forum member, who suggested 12 - 15 gr., said that's what he uses, but that it would probably take more. If it was a .30-40 Krag chambering I think TbG's suggestion would be a good place to start, or maybe a starting load of IMR 4895. Then, there's the 12 gr. of Red Dot load that many use as a started in old military rifles. I was tempted to try that, but the cartridge case is so cavernous I think I'd do better with the bulky Trail Boss. Anyway, perhaps someone "in the know" will chime in, as I know that there are many RB collectors and shooters out there.

Might want to try AA5744 works great with a 24 gr load in my 43 spanish using the Lyman bullet.

[Der Gebirgsjager]

Great! Another good lead. I'll write it down.....and I do have some AA5744. Thanks.

[brstevns]

I'd start out with about 30 grains of IMR 3031. Please post pictures when you start playing with that gun I would really like to see it.

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Will do. still wating to get it back from the Gunsmith.

[brstevns]

Will do. still wating to get it back from the Gunsmith.

Smith says next week, keeping my fingers crossed.

[brstevns]

I'd start out with about 30 grains of IMR 3031. Please post pictures when you start playing with that gun I would really like to see it.

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Here is a pic

[Rapidrob]

I've been shooting and reloading for the RRB for over 45 years now. All of the actors are just crazy strong. It is the design and the massive pivot pins that make them so strong.
I have RRB's today in .22 Magnum, 7x57mm, .40-65, 45-70, 50-110, and .50 Alaskan. I have never broken a part and never download due to the steel's age baloney.
There is no normal .30-40 Krag load that would be unsafe in your rifle. I would use a tight fitting cleaning patch and a tape measure to see what your rifling twist is. If it is tight ( 1:8 ") I would work up if using the 220 grain RNFB bullets.I've know several RRB shooters who had their rifles converted to .30-40 Krag and .30-30 Winchester and loved them.
I very good Navy buddy of mine hunts Bear in Alaska using his .348 Winchester RRB carbine.
I've only seen one RRB "blow up"in my 57 years of shooting centerfire rifles. And that was a moron who loaded BLANK powder in his beautiful original Creedmore .45-70 under a 500 grain bullet. The barrel was blown out of the action and the action was split for about an inch but both pins held! He was banned for life for being such an idiot at the range.

[wwmartin]

I built one last year on a #5 action in 9.3x74r using a Green Mountain .338 barrel that I had JES rebore to 9.3 - 4 gruve . The #5 according to Wikipedia was chamberd in some cartridges with pretty impressive preasures .
Others I've chamberd are 25-20 WCF , 25-35 WCF, 32-40, 40-82 WIN, and I have a 40 caliber and a 338 that aren't chamberd yet.
I tend to get carried away when I'm having fun .
Bill

[Drm50]

I’ve had 3 smokeless action RBs. Two 7mms and a 30/40. Shot 30/40 a good bit with 200cast and mild load of IMR-3031. I remember vel to be about 2000fps.

[8mm]

I own a Lone Star RB in 30-40 that I acquired on an impulse buy several years ago. One of the best gun purchase "decisions" I have ever made. I called Dave Higgenbottom the builder for advice on jacketed bullet loads and he said that any published load within reason was acceptable. Considering the outstanding quality of this rifle I decided that out of respect for this rarity it would be for cast bullets only. A decision with no regrets and much enjoyment.

[Texas by God]

Here is a pic

Nice!

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[brstevns]

Texas by God, Sorry it took so long to get a picture.
Check my post My Butcher Block Stock and you will see why.

[richhodg66]

I have really grown to like the .30-40 Krag as a cartridge. I like single shot rifles too. You have a very nice rifle there and you are a talented stock maker.

[brstevns]

I have really grown to like the .30-40 Krag as a cartridge. I like single shot rifles too. You have a very nice rifle there and you are a talented stock maker.

Thanks for your kindness