It Begins... .25 TCR!

[tinkerpearce]

So, my first rounds of .25 TCM are loaded.  These are made from .22 Hornet brass provided by Magnumwheelman.  


 
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.  

[bushog]

Real close to the 25 Special/25 flea

[tinkerpearce]

Apr 5, 2019 20:40:35 GMT -5 bushog said:

Real close to the 25 Special/25 flea

Hmmm... not familiar. I'll Google it.

[scotth]

i really like that can you tell us more about it is it 251 bore or 257 what was the process to swage down the brass thanks

[tinkerpearce]

Apr 6, 2019 10:42:39 GMT -5 scotth said:

i really like that can you tell us more about it is it 251 bore or 257 what was the process to swage down the brass thanks

It's a .251; there are many good reasons I might have done .257, but the fact is that my rifling button is .251, so that's that. The process to swage down the brass isn't rocket-science. While eventually I hope to use a modified .25 ACP resizing die, for now I simply bored a hole in a block of steel the correct size- approximately .276"- and drive the annealed and lubricated brass into it with a hammer and a block of hardwood. I use a 3/16" mild steel rod to drive it back out. Crude, but effective. I insert a /14" steel rod into the case, chuck it up in the drill-press and turn the slightly thicker base down to size. This is good enough for prototyping, but eventually I need a better method, which is why .25 ACP dies will be winging their way here.

[bushog]

Apr 5, 2019 21:51:10 GMT -5 tinkerpearce said:

Apr 5, 2019 20:40:35 GMT -5 bushog said:

Real close to the 25 Special/25 flea

Hmmm... not familiar. I'll Google it.

This is a .257 so not like yours....

[magnumwheelman]

TCM... Tinker Centerfire Magnum???

there is already a 22 TCM... so it may get corn fusing...

Nice looking cartridge...

my 257 Special... formed & trimmed case next to a formed 22 Hornet case...



trimmed case length... no turning of case mouth, or rims...



a Good start... more bullet options in 25 caliber rifle diameter (257)

[scotth]

i do like this a lot there is a guy on cast boolit forum chev wiliams that plays with the .251 bullet with 5.7x24 i think and hornet brass. looking forward to reading more about this.