I have a 1955, 25-2 in 45 acp. I want to buy a new 45 acp cylinder and have it reamed out for use with 45 long colt ammo. Is this reasonable ? I know the auto rim has a .090 rim and the long colt has a .060 rim thickness. The 25-2 cyl. is 1.62" in length, well long enough. I'd like to load the long colt ctg. to acp or acp +p pressures of 20,000 to 23,000 p.s.i.g. for hunting w/a 255. gr. swcl . Any thoughts on this project welcome !

I'd leave the 25-2 intact, assuming it is in great condition and simply find a good used 25-5. The 25-5 came in long colt and they are fairly common too.

Or, you could simply get some .45 Super ammunition and use this for hunting in your 25-2 immediately with no modifications . . . assuming your 25-2 is in sound shape!



.45 Super uses .45ACP dimension cartridge measurements but the cartridges are much stronger.

In .45 Super you'll get the following from a 230 gn bullet: Muzzle velocity: 1,100 Energy: 618 ft. lbs.

That should get the job done. If not, I'd look at getting a .41 Magnum or .44 Magnum S&W that will do the job more adequately.


I believe that S&W says that folks can safely fire .45 Super ammo in an unmodified Model 625. They don't say anything about the earlier 25-2, and shouldn't since the newest of these guns was made over a quarter of a century ago and who knows what kind of condition each specimen is in.


BTW, your third option is having the gun modified for shooting .460 ammo. In any event . . .


CONSULT YOUR GUNSMITH FOR INSPECTION AND ADVICE!


Again though, you'll destroy the value of a nice 25-2 converting it to .45 LC, plus, it ain't that cheap to do it correctly.

T.

PS: Welcome to the forum!

Converting an M25-2 .45 ACP to .45 Colt by adding a reamed out .45 ACP cylinder is NOT a good idea! Here's why"

1. As you noted in the cartridge rim thickness dimensions, there will be an excess casehead-to-recoil shield space of 0.030". That is a LOT, and will result in unreliable ignition and undue case stress on the .45 Colt cases, assuming the cartridges fire at all.

2. The excessive casehead-to-recoil shield space creates even MORE problems if you load the .45 Colt even slightly hotter. Difficult extraction, casehead separation, primer punctures, and so on.

3. A proper conversion requires a longer cylinder, properly fitted for headspace, endshake, and barrel-to-cylinder gap, and cutting back the frame lug that stops cylinder rearward movement.

Anything less that a full-up conversion properly done will give less that satisfactory results!

If your are really interested in the cartridge interchangability and not just the S&W factor (not bad in itself), may I suggest just getting one of the Ruger Blackhawk .45acp/.45Colt convertibles.
For much less than the conversion you will have what you want in a stronger package. I have two of these and they are great shooters, SA only of course but fill the bill if you can put up with that.
I hand load for both cartridges and enjoy the ease of changing out cylinders and feel a lot safer loading to higher pressures than I trust my old 25-5 with. Probably safe enough with my handloads as I don't 'hotrod' them in either gun, but I can squeeze more pressure/velocity out of the Blackhawk's than I feel comfortable with in the Smith. I don't feel the effort is worth having the 25-5 shoot loose when I can do the same in the Blackhawk.
RD

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