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After reading my latest Handloader Magazine concerning the article on the 7mm TCU rifle, A faint recollection stirred in my fuzzy memory. I seem to recall when this cartridge was introduced that one could take a standard .223 round and fire it in the TCU barrel, thus fireforming the case. I know that the bullet would just rattle on down the bore, but does anyone else recall such an article? Perhaps it was in a Guns & Ammo magazine years ago...:confused:
 

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After reading my latest Handloader Magazine concerning the article on the 7mm TCU rifle, A faint recollection stirred in my fuzzy memory. I seem to recall when this cartridge was introduced that one could take a standard .223 round and fire it in the TCU barrel, thus fireforming the case. I know that the bullet would just rattle on down the bore, but does anyone else recall such an article? Perhaps it was in a Guns & Ammo magazine years ago...:confused:
Tom,

I have never read anything to that effect and if it is theoretically possible, the logic escapes me. Without the bullet engaging the lands to provide resistance, and all that is entailed there, I can't imagine enough pressure building up to blow out the case properly. Not to mention that it just sounds dangerous, to me...if the tip of that little bullet "snagged" on the edge of a rifling groove, or started to come apart, I can see lots of bad things happening.

I could be wrong, but I think your fuzzy memory is referring to firing something like a standard '06 case in an 30-'06 AI chamber...apples to apples, basically. In other words, if the wildcat you're blowing out to and the parent case are both the same caliber, you can probably use that logic, but not when the loaded parent cartridge uses a bullet of much smaller diameter.

Jason
 

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The 7mm TCU dies had a tapered expander ball. You ran the cases over this ball then seated a bullet and fire formed the case.
Shooting a 223 round in a 7mm TCU chamber is like throwing money on the ground just a waste of materials.
 

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Discussion Starter · #4 · (Edited)
Like I said, it was just a fuzzy memory from a long time ago. I know about the '06 and the '06 A.I., as I have one, and as a bad idea, well, I don't think that if I had a 7mm TCU I'd try it, at least without further research.

When I read the article years ago, I wasn't doing any case reforming and thought that people who did so were a bit on the witchcraft side...but now I are one...! This spring I'll be having my 30/30 turned into a 30/30 A.I.




O.k. A bit more digging and i found out that indeed, I was wrong. It ain't the first time...
 

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My dad fireformed cases like that when he messed around with sihouettes many years ago. Worked OK for him and didn't seem to harm any thing.

Probably better ways of doing it, though.
 

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I believe the blow back gasses would float the case leaving a black residue on the outside of the case, seems there was a thread about 30/30 primers protruding after firing, the last bit if information provided by the original poster was something 'O yea there was a black residue on the outside of the case'.



F. Guffey
 

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Does anyone remember

For a couple of decades I shot the 6 and 7TCU in break open contenders.

Of the tens of thousands of rounds fired in that period of time I can't think of any reason to attempt to fire without expanding first. I am thinking that if one could ignite the primer one would blow the neck off the case. AT the very least weaken it.

SImple process to expand with a tapered expander and nearly as easy if one has a pile of military ammo to use a collet bullet puller and remove the bullet.

Neal
 

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I have successully done this with the .308, turning it into a .358 Winchester case.
Some I did using factory rounds and they all fireformed perfectly, without any gas blowback, or any of the other potential issues mentioned above.
I have also done this with my own bullets, usually cast, but some once fired collected when the snow melted. I have used Unique with those bullets, usually at the upper end for the bullet weight. Again, complete neck expansion without any issues.
The bullets do not rattle down the bore, as best as I can tell. They do tumble, but you can be fairly close to the tin can at 50 yards.
 

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I have 3 T/C Contenders chambered for the 7mm T/CU and it is one of the most accurate handguns I own...

Back in the late 80's and early 90's when you could actually buy a box a factory loaded 223 ammo for $2.99 at the gunshows that made with good Winchester brass, I have fired several thousand of these rounds through my 7mm T/CU barrels and they fireformed perfectly. No where around could I buy 20 pieces of new brass, new primers, powder and 20 bullets for $2.99....

A
 

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I have 3 T/C Contenders chambered for the 7mm T/CU and it is one of the most accurate handguns I own...

Back in the late 80's and early 90's when you could actually buy a box a factory loaded 223 ammo for $2.99 at the gunshows that made with good Winchester brass, I have fired several thousand of these rounds through my 7mm T/CU barrels and they fireformed perfectly. No where around could I buy 20 pieces of new brass, new primers, powder and 20 bullets for $2.99....

A
Well I'll be... I stand corrected! :eek:
 

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I did 32 years in the service as a weapons type. My buddy, a weapons type also got a 14 inch 7 TCU. We went to the magazine and got a can of the 5.56 55 grain ammo and went to the range to fire form that ammo into 7 TCU. We did about 400 rounds. For us that was the way you did it. The Dillon primer pocket swager really does a nice job of forming the primer pockets. Ah, to be young and have access to all of that ammo again.
 

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Discussion Starter · #12 ·
You guys tellin' me I ain't really crazy after all?

Imagine that.......!
 

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I think the article you remember was written by Dean Grennell and was about the .25, 6mm and 7mm TCU cartridges. I vaguely remember it as well....maybe the mid-80's?
 

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Discussion Starter · #14 ·
Hard to say when. I know it was since I graduated High school in 1971;)
 

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I don't see why it wouldn't work, but I would not have a brake on the end of the barrel or flash suppressor. I have fire formed a lot of brass in .348 Winchester to .50 Alaskan with a small charge of pistol powder topped off by corn meal sealed by a little wax plug. Messy as all get out but it fire forms the case perfectly. Just point it up in the air and let her rip. That worked until I got some case forming dies but they still needed to be fire formed to finish forming and if I wanted to wait until I could get to the range, I'd use a .50 cal round ball over a start load of powder, if not, get out the corn meal and wax plug.
 

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25/223 etc!

I necked the 223 case to about everything there was to nrck it to. Anything above .224 I just used 223 gauges in the chambering operation and used cheap BiMart 223 loaded amoo to fireform up. All you are doing id enlarging the neck! Never had any problems at all.
Aloha, Mark
 
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