.455 HE2/ acp alternatives

LNBright

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I've a couple of 22-4 .45acp revolvers (one 5-1/2", one 4"), that I'd gotten to be shooters instead of flogging some collectable M1917. I'd wanted an M1917 for years, kept searching for, contemplating on, but for whatever reason, always ended up passing, or dragging my feet and they sold before I decided, etc. (Nice ones were more than I was interested in investing in, and the easily affordable ones were, usually rougher than I'd want to deal with.) But, I kept keeping my eye open...

The other evening, there was a gun advertised as a 1917 .45acp, looked a little rough in the pics, thought it might've been a Brazilian as the price was low, but I thought it'd do to mess around with, not being collector-worthy, so okay, got it shipped to my FFL and picked it up yesterday. And, here's where it got interesting. It's not a M1917. It's a .455 HE2 that had the cylinder cut to fit .45acp w/ moon clips. So, a cut cylinder, still not 'collectable', will be okay to shoot a bit. And the pictures were a bit misleading: it's nowhere near as rough as I expected it to be. Sure, it's got its share of nicks and scratches, some bluing missing, but it's honest wear. I've started cleaning it up a bit. (It had a burr where the backstrap meets the butt, I stoned that off; and the lanyard was frozen, a drop of PB blaster followed by some 3in1 oil, and it's freed up now. There was a little rust under the stocks, I stoned it off too).

Here on this site, I've now been wearing out the search tool, reading up. I'm getting up to speed on the fact that the HE2 .455 cylinders weren't heat-treated the way the M1917 ones were. Seems what would have been a better conversion would've been to have been gone w/ .45LC, as its chamber pressure would be more inline w/ the .455, and that the acp pressure is the 'proof' pressure for the .455, so, I really don't want to go using commercial .45 acp rounds in it. (Doesn't appear that it has an swelling, but, I don't want to be the one on whom it bursts while in my hands, so....). But since the cylinder is cut, I can't just switch to using .45LC now, as the pin probably wouldn't reach the primer.

So, I'm pondering options.


A) Start reloading. Use .45acp brass but load at .455 pressures. But that's a whole other kettle of fish.

B) Locate a replacement cylinder.
B1) Will a M1917 cylinder fit a HE2? It appears identical in dimensions to my 22-4 cylinders. Either a new cylinder (though its bluing wouldn't match), or if I could find a M1917 cylinder, as it would be heat-treated, I could then proceed with using regular .45acp safely, correct?
B2) OR, find yet another .455 cylinder, and have the chambers adjusted for .45LC, and go with reduced cowboy loads to be safe.

C) Other alternatives? I'm open to suggestions. Overall, I'll still put more rounds through the 22-4's, they're both fine shooters. (I'm used to .45acp (also run in 1911s).) But I don't want to just stick it in the safe and never use it, I want to 'get it up and running'. I've not found commercial 'reduced load' acp rounds, that would be a simple solution, if such existed. If plastic moon clips are used, can you clip a .45LC shell into it, using the clip to position the casing so the primer gets struck? I don't think that'd work, as it'd leave a portion of the back of the case proud of the chamber's lip; but, if I could use .45LC in this cylinder somehow, that simplifies things, too.

Suggestions, comments, caveats, all are welcome.

Regards,
 
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Measure your Cylinder Bores, and Barrel's "Grove to Groove".

The .452 of usual .45 ACP and .45 Auto-Rim are likely quite a bit too small for this Bore.

So, if to be using .455 or .456 Diameter Bullets, you need to expand the Cases and also obtain a right size Die for Crimping.
 
Welcome to the Forum.

A 1917 cylinder is slightly shorter than .455 cylinder, due to the increased headspace necessary for the thickness of the moonclips and/or the .45 Auto Rim cartridge rims. This means if you extract vigorously, the rear of the 1917 cylinder will hit the cylinder stop quite hard. If you are reasonably gentle, no harm will be done.
 
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If you want any accuracy, plan to reload, particularly if you don't want to spend a fortune. Slug your bore, or at least run a pin-gauge through your throats, and buy bullets accordingly since you have bought a beast that wants special feeding.

As has already been pointed out, running .452" bullets in that barrel isn't going to be very accurate at all. Your throats will be too big for .452" as well, so expect poor accuracy and dirty brass.
The good news is the bore is so loose that normal .45ACP will operate at lower pressures because of it.
The rifling is very shallow, so lead bullets are the order of the day if you don't want to erode the rifling, which jacketed projectiles will surely do over time.

I third the idea of using AR brass, since that way you won't accidentally feed some ~.454" bullets to your newer guns.
I never needed special dies for my oversize reloads though, these low power loads hardly need any crimp anyway I've found.
 
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Sounds like I finally have the excuse to get into reloading: it has been on my ‘round to it’ list, just had never actually jumped.

I’m used to moon clips, they don’t bother me, so I’m fine with them; but I appreciate the notion of sticking with a different round for it as a safe-guard from accidentally dropping a commercial ACP load into it. I’ve never even thought about auto-rim rounds since I wasn’t opposed to moon clips, but they do make sense here, don’t they?

Glad to have found a good place here to learn more about these older S&Ws…

So, now to learn more about reloading….
 
Another option is to find an N frame cylinder for a smaller cartridge, and have that cylinder rechambered to wherever cartridge you want to use in that frame. The ejector rod threads need to match so getting a cylinder from the correct era is necessary.

Kevin
 
I don’t have a S&W 455 right now but have a Colt 455 Eley. I have been using a 45 cal rifle bullet, modified to 272gr. I was trying for 265gr but let well enough alone. Cast soft and sized .457” and shot at approx 600fps with 4.5gr Unique. The powder charge was to “ focus “ for 50’ shooting.
 
"Matts Bullets" has proper actual .455 Webley Bullets ( Lead ), and can also size their various erstwhile .452 Bullets, to .455 if one wants.

Last time I was loading for my 'converted' 2nd Model HE I had to resort to a Crimp Die for 45-70 ( an old Ideal '310' Die ), since the supposed .455 Die Sets I had gotten were not 455 at all, but were for .452, and would not work, and the too small of Crimp Die would also get the Bullet stuck in it for being too small.

As it happens I am about to get back in to Loading for one of my 2nd Model HE .455 but converted to .45 Colt ones, so I have to solve these challenges all over again.

I hope I still have the old IDEAL '310' Die Set for .45-70.
 
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I don’t have a S&W 455 right now but have a Colt 455 Eley. I have been using a 45 cal rifle bullet, modified to 272gr. I was trying for 265gr but let well enough alone. Cast soft and sized .457” and shot at approx 600fps with 4.5gr Unique. The powder charge was to “ focus “ for 50’ shooting.
I use Lee .455 Webley dies to load for my 1915 Colt New Service in .455 Eley. I get my bullets from Reed's Ammunition and Research, LLC. They sell .455 sized bullets in two styles...a 265 gr round nose, hollow base and the 255 gr hollow point, wadcutter "Manstopper".
 

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The 455 case body is slightly larger than the 45 acp ... you will get some swelling when 45 acp are fired .

The cylinder has been shaved back for use with moon clips and 45 acp brass.

The easy option is to reload your empties ... and Partially Sizing the case ... enough to hold the bullet but not full length , this avoids over working the brass . Reloading allows you to load light / med. pressure loads ...so the brass doen't over expand .

You have two options : 45 acp cases in moon clips ... OR ...
... 45 Auto Rim and no moon clips .

What I do is use Starline 45 AR cases ( I dislike fooling around with moon clips) , just for use in this revolver and Partial Size and light / medium pressure loads with cast bullets !
Works like a Charm !
Gary
 
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I believe that the bullet for 455 Mk II was supposed to be .454, the same as 45 Colt. .002" is certainly not significant when talking lead bullets and should fire in a smaller barrel. I would almost certainly predict that during the war, these revolvers shot anything available, including ammo intended for the Model 1911, without any known problems I am aware of. Out of respect for the age and value of these vintage military guns, I always suggest loading for 700 fps or less.

As for accuracy, the 455 and Model 1917 were no prize winners. I have an original 455s, a 45 Colt re-bore, and a 45 ACP conversion and have shot them together, finding no noticeable difference in accuracy at 25 yards loading the same velocity and bullet. Past information that I have ran across indicated that the standard bore was set to for the Model 1917 was specified at .4505", but that in reality the measured bores have been recorded from .450" to .456" in Model 1917 Colts and S&Ws, probably lending to the reality that accuracy was questionable in all the N frame military revolvers.
 
I believe that the bullet for 455 Mk II was supposed to be .454, the same as 45 Colt. .002" is certainly not significant when talking lead bullets and should fire in a smaller barrel. I would almost certainly predict that during the war, these revolvers shot anything available, including ammo intended for the Model 1911, without any known problems I am aware of. Out of respect for the age and value of these vintage military guns, I always suggest loading for 700 fps or less.

As for accuracy, the 455 and Model 1917 were no prize winners. I have an original 455s, a 45 Colt re-bore, and a 45 ACP conversion and have shot them together, finding no noticeable difference in accuracy at 25 yards loading the same velocity and bullet. Past information that I have ran across indicated that the standard bore was set to for the Model 1917 was specified at .4505", but that in reality the measured bores have been recorded from .450" to .456" in Model 1917 Colts and S&Ws, probably lending to the reality that accuracy was questionable in all the N frame military revolvers.

No, one can not chamber and use .45 ACP in an un-modified .455 Webley Chambering...the Round falls too far in to the Chamber ( just as it will with .45 Colt )...and .45 ACP in Half Moon or Moon Clips, is much too thick at the Head-Space, and leaves no room for the Cylinder to close.

No one was using .45 ACP in their un-modified Webley, S & W, or Colt .455 chambered Revolvers, in WWI or since.

The Cylinder has to be shortened / modified to accept .45 ACP and the .45 ACP has to be in Moon Clips or Half Moons etc. in order to function.
 
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Also...

.45 ACP standard Loading is expected to run at about 21,000 PSI.

.455 Webley, around 13,200 PSI.

.45 ACP is more or less a "Proof Load" for .455 Webley, in terms of pressure.
 
Also...

.45 ACP standard Loading is expected to run at about 21,000 PSI.

.455 Webley, around 13,200 PSI.

.45 ACP is more or less a "Proof Load" for .455 Webley, in terms of pressure.


Which is why I was looking for something for this particular revolver other than factory ACP.


I wish I could find a low-pressure factory load in either ACP or Auto Rim, but the only Auto Rim turning up in searches yet is Buffalo Bore, at a price that quickly pushes me into thinking about reloading anyway. And all ACP is standard or +P, not reduced P....
 
No, one can not chamber and use .45 ACP in an un-modified .455 Webley Chambering...the Round falls too far in to the Chamber ( just as it will with .45 Colt )...and .45 ACP in Half Moon or Moon Clips, is much too thick at the Head-Space, and leaves no room for the Cylinder to close.

No one was using .45 ACP in their un-modified Webley, S & W, or Colt .455 chambered Revolvers, in WWI or since.

The Cylinder has to be shortened / modified to accept .45 ACP and the .45 ACP has to be in Moon Clips or Half Moons etc. in order to function.

Where to start??? This thread includes discussion about both the 455 and the 1917 45 ACP. Thought it was obvious I was referring to the US Model 1917 using Model 1911 ammunition since the British had only a handful of Model 1911s, so the comment did not apply to the 455. The only thing needed to convert the 455 post-war was to shave off the rear of the cylinder and extractor star. I mentioned that I own and shoot all three options for the 455 and mentioned that one needed to convert 455 to shoot 45 ACP and re-bore for 45 Colt.

45 Auto-rim can be a pain to shoot in a revolver since the brass often falls through the extractor star because the rim is too small. Reloading is the only way to go in order to shoot 45 ACP in a converted 455, but the option of finding a Model 1917 cylinder and star assembly is a good one if one shows up. ebay has three 45 ACP cylinders, currently one blued and two stainless from a Model 625 but all expensive.
 
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