| TN_Longhunter |
| (.224 member) |
| 03/01/06 02:36 PM |
Unknown Cartridge-Help
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I have a very nice 1898 Krag (Springfield) sporter. Stock has been cut down, Receiver sight, non-mil front sight. No markings of any type on the barrel. One round of 30/40 Krag taught me not to "know" what caliber a rifle is in. Heavy recoil and the case was split with almost no neck left. The sholder and neck had blown out. I pulled a chamber cast and this is what I found. 30/40 Krag rimmed base, 0.478" dia. just forward of the rim, 2.93" from base to neck, with a body of 1.925". Still .308 caliber. This cartridge is longer than a 30/06 and is rimmed. I have searched several books (COW, Hogan and the Boyem series)with no luck. If it is not a wildcat then what is it? Most Krags are necked down if anything. I'm hopeing that this is a known cartridge and that I can get it shooting.
| DoubleD |
| (.400 member) |
| 04/01/06 04:04 AM |
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Re: Unknown Cartridge-Help
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Need a lot more information.
Can you post a picture of the chamber cast?
Does the chamber cast show the chamber is a bottle neck? What is the length to start of shoulder; to start of neck
Can you give an OAL of the chamber?
What is the diameter of the neck of the chamber cast. What is the diameter of the shoulder on the chamber cast?
Have you slugged the bore?
| mhb |
| (.275 member) |
| 04/01/06 04:35 AM |
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Re: Unknown Cartridge-Help
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At this point, you might give more dimensional data on the chamber cast - diameter at shoulder, neck length and diameter, etc. Sounds like an 'improved' Krag, but specific measurements would help with identification. And a further confusion is due to the measurements you did give: the basic Krag case is only 2.314" long: how would you get one to fire-form over half an inch longer?
mhb - Mike
| TN_Longhunter |
| (.224 member) |
| 05/01/06 02:57 AM |
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Re: Unknown Cartridge-Help
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Thanks for the suggestions. Had some trouble with the site but here is more data and a link to a photo.
Overall length- 2.50"
Base dia- 0.478"
Base to shoulder- 1.925"
Neck length- 0.321"
Shoulder length- 0.188"
Dia. at shoulder- 0.445"
Bolt has not been modified from the org 30 US Krag.
Photo can be seen at:
http://i25.photobucket.com/albums/c85/TN_Longhunter/KragCast.jpg
I did get with some semi pro friends of mine (own the Reloaders Bench) and after much searching the best we could come up with is a 30/06 rimmed. Minor differences in some measurements but very close and may to due to the reamer used. Howell's book says to neck down 400/350 brass to form. After looking over the brass they had I think we found something that would work. They had a box of RWS 30 Blazer (?) that could be trimmed, run through 30/06 dies and then fireform. Before I go that route I'm going to see what others have to say.
| TN_Longhunter |
| (.224 member) |
| 05/01/06 03:00 AM |
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Re: Unknown Cartridge-Help
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Forgot one question asked. Bore is .309. and that is a 30/40 Krag next to the chamber cast in the photo. As you can see there was a lot of room for the cast to blow out when fired.
CptCurl
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| (.450 member) |
| 05/01/06 03:45 AM |
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Re: Unknown Cartridge-Help
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If it is a .30/06 rimmed, which it does look like, you can use 7x65R with a cream of wheat fireform, and very little trimming, or you can trim 9.3x74R and neck it down.
Hope this helps.
Curl
P.S.
Be really careful with your pressures.
Curl
| TN_Longhunter |
| (.224 member) |
| 05/01/06 05:37 AM |
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Re: Unknown Cartridge-Help
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Thanks, I hadn't thought of the 7X65R. I compared the 9.3X74R and thought that it was case I was looking for but the rim is smaller than the 30/40 and I'm not sure about extraction. As to loads (if I get that far) it will be mild cast bullet loads for an '06. The Krag action is a nice one but not one that I'm going to try max loads with. I would like to get it shooting even if it is a target/plinking load.
| foxfire |
| (.375 member) |
| 05/01/06 05:48 AM |
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Re: Unknown Cartridge-Help
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Here are some figures for the 7x65R from
"Cartridges of the World" 4th edition copyright 1980.
Hope it helps.
7x65R:
Bullet Dia. = .284
Neck Dia. = .308
Shoulder Dia. = .422
Base Dia. = .463
Rim Dia. = .521
Case Length = 2.53
Cartridge length = 3.21
| TN_Longhunter |
| (.224 member) |
| 05/01/06 05:55 AM |
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Re: Unknown Cartridge-Help
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Looks like it would fireform to fit with very little trimming. The rim is 0.021 smaller than the 30/40. Same problem I would have with the 9.3X74R.But it might work fine. Looks like I have some options and may be able to shoot the ol gal'.
| DoubleD |
| (.400 member) |
| 05/01/06 06:04 AM |
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Re: Unknown Cartridge-Help
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I echo CPT Curl's warning even louder. Be careful of pressures. Personally I wouldn't consider the 30/06 rimmed or a regular 30/06 safe in a Krag. Hatcher warns the Krag shouldn't exceed 42,000 pounds
| TN_Longhunter |
| (.224 member) |
| 05/01/06 06:38 AM |
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Re: Unknown Cartridge-Help
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When I get it shooting it will be with a very, very mild load. Much below what the Krag was meant for. The idea of a '06 in a Krag scares me. As to my earlier post, very mild plinking and target load.
| mhb |
| (.275 member) |
| 06/01/06 03:35 AM |
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Re: Unknown Cartridge-Help
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Many early wildcat cartridges were also based on the .405 Winchester case (or the very similar, earlier .40-72) - which would almost certainly meet the dimensional requirements of your chamber, if properly reformed - this case is currently available, after many years' absence.
mhb - Mike
| TN_Longhunter |
| (.224 member) |
| 06/01/06 11:27 AM |
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Re: Unknown Cartridge-Help
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Read your post and hoped it was the answer I was looking for. When I got home I checked it against some .405 Win. The rim is too thick and the base is 0.458" when I need 0.478". It might expand but then it might split. I think I'll save my 405s for my 1895 Winchester. A gun that is too much fun to shoot for it's own good. I have several options as to cases to use. Now to find the time to do it.
| mhb |
| (.275 member) |
| 07/01/06 03:46 AM |
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Re: Unknown Cartridge-Help
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Part of the mystery must be: What did the original maker use for brass, and what did he do for a chamber reamer?
In the 1920-1940 era, wildcatters had access to remaining supplies of many older and obsolete cases, and practically every one you can think of was wildcatted at some time. It is unlikely that a U.S. Krag would have been wildcatted for a European rimmed case, so the rifle was most likely intended to use some U.S. basic case. However, review of the dimensions of obsolete U.S. cases does not reveal any more likely candidate than the .405. Modern Hornady .405 brass (the samples I have) measures .461" at the base, and does have thicker rims than the typical Krag case, but I'd bet this was not always true of earlier production .405 brass, and, in any case, any wildcatter of that era (or this one) would have had no trouble thinning the rims, if necessary. When building rifles for rimmed cases today, I customarily survey the rim thickness of available brass and make the rim recess only deep enough to accommodate the average of those, with about .002" clearance, and adjust the rim thickness of thicker specimens if necessary.
As for the chamber dimensions: if the base of the chamber is as large as you report, there is no other common case which is really a better fit, though some real oddities like the .40-90 Sharps straight case come closer, and it is, of course, possible that that was the original base case. It is also possible (and not unlikely) that the reamer was made bigger than optimal at the chamber base, whatever brass was intended for it.
We'll probably never know - but keep us posted as you work-up loads, if you decide to shoot the rifle.
mhb - Mike