Converting a .455 Colt New Service to .45 ACP

deadman

deadman

CGN Ultra frequent flyer
Rating - 100%
169   0   0
Location
Southern Saskatchewan
I've got this old pistol sitting here, and was wondering if anyone can shed some light for me.

I know many .455 revolvers have been converted to other calibres, (S&W HE converted to .45 Colt, Webleys converted to ACP), and I've read that even though it was done, its not now recommended as standard .45 ACP pressure is akin to .455 proof loads. Having seen pics of these other pistols failing with the conversion, my question is this:

Was the .455 New Service built differently than the ACP version (M1917)? With that, S&W made an M1917 in ACP that was (as far as I know) the same as the .455, so why do people advise against converting them?

Anyway, I'd like to convert it if it'll hold up. Does anyone know if the ACP versions of the Smith and Colt were the same as the .455, or were they built stronger?
 
Trade it for a converted one.
The purists will be trembling like ' A Little Dog sh*tting hot razor blades ' when they read this, lol.
I'd posted something along these lines; about 3-4 unsolicited offers to trade came my way.
Easier to trade it for an already 'd*cked with' one IMO
 
Strength would not be an issue. Bore size would be. For good results with .45ACP, you would have to handload - basically rimless .455s. Easier to just stay with .455. Saves the cost of conversion and doesn't devalue the revolver.
 
Mine was converted by Canadian navy, so I'm told to 45 long colt. So if it can take that it can certainly handle ACP. The issue with rimless cases is that you would need to remove metal from cylinder back in order to accommodate moon clips. And you would need to replace extractor as well as the original won't work.
If you going to convert it then do it to 45 colt as its the only option that will work. Otherwise leave it original as others pointed out and either trade it for other revolver or take up 455 reloading, which is fun in itself.
 
Converting calibers on a Colt Is insanity, sell it and buy one in 45 Colt or 45 acp. The money you spend converting it will equal only in the amount you devalue the gun by doing so... The only exception would be if this gun is already perminantly butchered by some other gunsmith renovation, therefore already devalued.
 
I'd keep it original too, unless there are major cosmetic issues and it has limited collector value. 455 ammo is still out there. Not cheap I know but reloading is an option too. It would cost you something to convert it anyway.
 
tiriaq said:
A US M1917 is a fine option for anyone wanting a .45ACP New Service.
Click to expand...

That would be the ideal alternative, i was thinking of this one because I already have it.

Aside from that, I don't consider converting it "de-valuing" it. I don't load .455 and don't really have a great desire to do so. If it was converted to ACP then it would become a pistol I'd actually use, therefore more valuable to ME. Its not worth selling unless someone wanted to trade for one in ACP, because its a job I could do myself. And yes I'm aware of the necessary steps to accommodate moon clips/etc.

I'm also aware of people's opinions about modifying old firearms, I have a couple old ones too.

This isn't something I'd normally consider doing but its just sitting there. Would be a good project. Its not particularly valuable to begin with.
 
You might find that factory .45ACP ammunition does not shoot well through the .455 barrel. The bullet diameters and rifling characteristics are very different.
Spend money and wind up with a revolver that has lower resale value and indifferent performance.
 
tiriaq said:
You might find that factory .45ACP ammunition does not shoot well through the .455 barrel. The bullet diameters and rifling characteristics are very different.
Spend money and wind up with a revolver that has lower resale value and indifferent performance.
Click to expand...

That's definitely a possibility, I would likely use cast bullets which may help a bit (depending on their design). On the other hand resale value isn't my primary concern as its not worth much to begin with, so then the only gamble is how will it shoot. On the other other hand, I wouldn't be completely opposed to a trade but then I have to find someone with a .45 version that wants mine :d
 
You can always form .455 brass by trimming and shaving .45 Colt. You might get extractor skipping, but unless you're going to use it for competition it shouldn't be an issue.

You'll need to shave the rim from the front, otherwise you'll have extruding primers.
 
Found an answer to my question regarding the Smith .455 vs the .45. Apparently the cylinders on the .45 (M1917) were hardened, and were not on the .455 versions. So, that would be one mark against converting the Smiths. Wonder if the same for Colts?

Just thought I'd share in case anyone else was interested.
 
maxman1 said:
You can always form .455 brass by trimming and shaving .45 Colt. You might get extractor skipping, but unless you're going to use it for competition it shouldn't be an issue.

You'll need to shave the rim from the front, otherwise you'll have extruding primers.
Click to expand...

45 Schofield might be harder to source, but more suitable than 45 LC
 
I have one that has been converted to 45 Colt from 455....I can shoot both in it. Conversion that way is easiest, just need someone to drill the cyl a little deeper. Mine was converted probably 50 plus years ago, and is still going strong.
 
deadman said:
I've got this old pistol sitting here, and was wondering if anyone can shed some light for me.

I know many .455 revolvers have been converted to other calibres, (S&W HE converted to .45 Colt, Webleys converted to ACP), and I've read that even though it was done, its not now recommended as standard .45 ACP pressure is akin to .455 proof loads. Having seen pics of these other pistols failing with the conversion, my question is this:

Was the .455 New Service built differently than the ACP version (M1917)? With that, S&W made an M1917 in ACP that was (as far as I know) the same as the .455, so why do people advise against converting them?

Anyway, I'd like to convert it if it'll hold up. Does anyone know if the ACP versions of the Smith and Colt were the same as the .455, or were they built stronger?
Click to expand...

when you convert how 455 webley was pressure tested , it comes out to just over 1/2 way between 45 colt and 45 auto , for a standard load , not a proof load .

455 is easily available , unless it has become really expensive the last while ( or hard to get ) , your not saving much money by converting it .

*edit*

a thought just popped into my head , is it possible to get 45auto to properly headspace in the cylinder using the mouth of the case ?
without machining the rear of the cylinder down for moon clips ?

it may be possible to set it up to run both 455 and 45 auto .
 
Calgary Shooting Centre had a bunch of .455 in September and far as I know some as close a a month ago. $55 for 50. No reloading required. Just FYI.
 
My New Service is pitted and of no provenance that I can see. If any pistol should be converted...it'd be the one.
But finding a good 'Gun Plumber' is hard to do
 
It's not as simple as shortening the cylinder to clear the moon clip.

Part of the issue is the stud to stop rearward cylinder movement when the cylinder is open.

I've seen several that were ruined by cutting for 45acp.

New Service 455 targets are noted for chamber ing 45acp as their chambers are tight enough to head space on the cartridge mouth.

You just need to pick out the empties from the front of the chamber.
 
You must log in or register to reply here.
Back
Top Bottom