.25 TCR- It Begins!

So, my first rounds of .25 TCR are loaded. These are made from .22 Hornet brass.



For comparison, left-to-right- .22 LR, .25 ACP, .25 TRC and 9x19mm

The prototype load for .25 TCR uses a 50gr Truncated-Cone lead bullet over 2.3gr. of Unique. This should be a good starting load, though once things are rolling I'll see if I can get some 35gr. hollow-points and some other bullet types and weights, and try some other powders as well. The case is .90" long, and the overall length of this load is 1.11". If I did my math right- and it looks plausible that I did- this load will hit 1060fps. from a 4"barrel. To compare that to other small-bores from a 4" barrel:
.22LR CCI Stinger- 1191fps. 101ft/lbs.
.22LR CCI Mini-Mag 1014fps 91ft.lbs
.22 Magnum 1248fps 138ft./lbs.
.25 ACP 950 fps. 94ft./lbs.
.25 TCR 1060fp 125 ft.lbs

Since the goal is a reloadable .22 equivalent that can be loaded from .22 LR to .22 Magnum power levels this looks like a good place to start. Now I have to make a gun that shoots it... The test gun will be a stout single-shot; I'll probably rebarrel one of my existing home-made pistols for this.

TCR stands for Tinker Centerfire Rimmed. I'm forming the brass by cutting, annealing and lubricating the .22 Hornet brass, and then driving it into a .276" hole drilled in a block of steel, and driving it out with a 3/16" mild steel rod. Then I insert a 1/4" steel rod, chuck it up in the drill-press and turn down the slightly thicker portion just ahead of the rim. Crude but effective, and good enough for prototyping. Eventually I want to use a modified .25 ACP resizing die; this ought to be a lot simpler!

As to the idea of a Ballard or Low-wall, finances and time permitting I'd planned a rolling-block rifle in this caliber. I've already mentioned that I plan a single-shot pistol for testing, but if I can ever get the thrice-cursed 3-phase inverter working so I can use my milling machine, I intend to do a revolver. I might be able to do one without the mill, but it really would make the process better and easier.

Random 8 said:

Might it be easier to keep the ~ .290 body diameter and neck down slightly in a .25 ACP or modified .25-20 die?

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It's a thought, but I really want a straight-walled cartridge. It just seems like it simplifies things- especially if it allows me to use .25 ACP reloading dies.

Random 8 said:

Not a pro on wildcatting, but once you have a chamber, brass would be fireformed once (oversized) then formed in the neck area only with .25 acp? Really interested in this project, sorry to butt in, but lacking the tools and know how on this sort of thing, I like to live vicariously.

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No worries!

RedlegRick said:

This is fascinating. While I'm as far from a wildcatter as you can get, this topic intrigues me. I'd have thought it would be easier to replicate the 5.6 VeloDog in order to use pre-existing .22 barrels, but this is pretty cool in its own right.

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It's actually been done- .22 Cooper Centerfire Magnum

tactikel said:

OMG you recreated a .25-20! 100 years after the fact.

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Oh, this case won't hold anything like 20 grains of BP, and .25-20 will dramatically outperform this round; typical modern loads generate 400 ft./lbs of energy at the muzzle

JohnMc said:

Not to mention that rimfire ammunition doesn't age as well as center fire.

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I dunno- I'm currently working my way through seven bricks of fifty-year old Sears brand .22LR that I inherited- been dead reliable so far! More than I can say for the relatively new brick of Winchester Wildcat a buddy gave me...

JohnMc said:

My data is from stuff I've tried to store after the "great shortage." The failure rate seems to have gone up over time so, yeah, it's anecdotal. It's bulk Rem or Federal. Because of that, I did some searching online and read that the primer compound can fall out/flake out of the rim plus .22 isn't as air-tight as center fire apparently..

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Interesting. The Sears stuff was made by Federal... albeit fifty years ago. I've heard about a lot of problems with modern 'bulk' ammo from Remington, Winchester and Federal.