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  • Blue Diamond

    sportsman
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    I found a round in some misc. cartridges that someone gave me and don't know what it is. I thought 1st it was 308 but it is not. It is 1/4 inch shorter than a 30/06 and is a 30 caliber miking .308 and has headstamp of T W 5 4. Anyone have an idea? The base/rim mikes the same as 30/06
     

    DAVE_M

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    TW54.JPG
     

    Magdump

    Don’t troll me bro!
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    A pic would be great.
    Best of my recollection that’s a Twin Cities Arsenal headstamp.
    If it’s a .30 cal (or .308 cal) projectile then measure the case length. If it’s 51mm then that’s likely a 7.62x51 round or .308 Nato. I’m not sure what all they produced at Twin Cities over the years, but definitely most of the US small arms calibers and .50 BMG well into the 70’s. They got shut down for some EPA stuff later but I’m not sure why.
    Lemme try to do some research.
     
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    DAVE_M

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    A pic would be great.
    Best of my recollection that’s a Twin Cities Arsenal headstamp.
    If it’s a .30 cal (or .308 cal) projectile then measure the case length. If it’s 51mm then that’s likely a 7.62x51 round or .308 Nato. I’m not sure what all they produced at Twin Cities over the years, but definitely most of the US small arms calibers and .50 BMG well into the 50’s. They got shut down for some EPA stuff later but I’m not sure why.
    Lemme try to do some research.

    If you took me off ignore, you could see the answer is right in front of you...
     

    Blue Diamond

    sportsman
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    A pic would be great.
    Best of my recollection that’s a Twin Cities Arsenal headstamp.
    If it’s a .30 cal (or .308 cal) projectile then measure the case length. If it’s 51mm then that’s likely a 7.62x51 round or .308 Nato. I’m not sure what all they produced at Twin Cities over the years, but definitely most of the US small arms calibers and .50 BMG well into the 70’s. They got shut down for some EPA stuff later but I’m not sure why.
    Lemme try to do some research.

    The case length is 2.30"
     

    Magdump

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    So, you’re saying something the equivalent of 7.62x58.5 then?
    Only round I know with those dimensions is 30-40 Krag but the rim is not the same as 30-06.
    I may be wrong, but I’d assume that the round would have to be an American military load if it came from Twin Cities. As far as I remember, they were up and running off and on for wartime ammo production. Korea, Vietnam... I’m not aware of any commercial loading or loading for any international military ammo.
     
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    Magdump

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    Blue, by any chance, is there an actual projectile in the case or is the case crimped or capped or possibly a training round projectile? It may be a 30-06 (7.62x63) blank/training round/ grenade launching round and the crimped case is preventing an accurate measurement.
     
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    dougstump

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    It sounds like a GI 30-06 case reformed to 7.7mm Jap. I used to do that back when I had a couple of Type 99's.
     

    dougstump

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    Can you please measure from the base up to the shoulder?
    1.8189 would be 7.7 Jap
    1.7569 is 7.65 Mauser
    1.750 = 7.5 French
     

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    Blue Diamond

    sportsman
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    Apr 12, 2014
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    Can you please measure from the base up to the shoulder?
    1.8189 would be 7.7 Jap
    1.7569 is 7.65 Mauser
    1.750 = 7.5 French

    As previous stated case length is 2.30"
    viewer.php
    [/URL][/IMG] Well finally figured out how to get picture placed. Middle cartridge is unknown with 06 on left and 308 on the right.
     
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    dougstump

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    Not the overall case length, the length from the base to the shoulder.

    Also, what is the boolit diameter?
     
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    Magdump

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    Well it’s obviously not a blank or training round. At this point I’ve got to question if it’s possibly a hand load using repurposed brass. I bet High Standard could figure this one out.
     

    dougstump

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    Bullet is .308 and shoulder length is +- 1.850; to base of neck is 1.980 case length is 2.30 rim is .470 oal is 3.030 Hope this helps.

    Wow, I love a puzzle! One more dimension that may help, the diameter at the shoulder. Unfortunately I am over at our weekend house in Texas and I neglected to bring the books I need with me. It might be Monday or Tuesday before I can put my hands on them.

    You clearly have a GI 30-06 case that has been reformed into something. In the photo you can see where the shoulder used to be. There are several possibilities:
    1. It's a military round.
    2. It's a wildcat or some obscure proprietary cartridge.
    3. Some "new" cartridge someone is working on.
    4. It's a practical joke. One time I necked a few 357 mag cases down with a 30 Luger die & left at the public range. I even left one "live" cartridge.

    I'll let you know if I make a positive ID.
     

    dougstump

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    Here's one I dealt with 30 some years ago. A guy I knew bought a Jap type 99 (7.7mm) but it wouldn't go bang, the primers had a tiny spot from the firing pin. Bad spring? Nope. The spring was very strong and firing pin protrusion was good, but the bolt was mis-matching. I stripped the bolt, including the extractor, chambered a live round and shook the rifle. You could hear the round bouncing up and down in the chamber. I started adding pieces tape to the base of the cartridge until I could feel a bit of resistance closing the bolt. The mis-matching bolt created about .060 excessive headspace! I took some .30-06 brass and with 7.7 dies slowly walked the shoulder back until the bolt would just close. Then loaded the formed brass with a light load. He was real happy that he could finally shoot it.

    It's possible your mystery round is from something like this. With a .308 boolit, it's doubtful that it was for a 7.7mm

    I just looked through a ballistic program I have here, "Load from a disk". While it has a database of 1134 cases (which I just imported into a spreadsheet!), there are no matches for the shoulder length and boolit diameter. I'll do more digging.
     
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    Magdump

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    I’m sticking with my educated guess. I think it’s a repurposed 30-06 brass. As for what, I can’t say. I reckon there might be a rifle out there somewhere that would shoot it, lol, but I don’t think that case started life in its current state.
     
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