3-Screw 45 Colt

[dwayne]

I am considering a OMBH 357, 5" barreled, 6-shot conversion to 45 Colt as a "packin' gun". I know that this frame is NOT suitable for the heavy loads necessary to hunt black rhino, grizzlies and other dangerous game. And, I will have no occasion to hunt these critters or be ambushed by them while walking the farm in Virginia. At the most, I'll have a rare occasion to hunt eastern whitetails. I can see using a ~255 grain bullet running 1100 fps (MAX). Most shots will be fired at paper in a backyard match with friends and family.

I remember reading a column about the different pressure levels of 45 Colt loadings and which frames are suitable for each, but I can't seem to locate it. So … I'm left with a question. Is the OMBH frame OK for moderate 45 Colt loads or should I give up on this as an idea? Any first hand experience that you think is helpful to me as I ponder this choice?

Thanks in advance for your help.

P.S. I have a beautiful 44 Special OMBH conversion already.

 

[Joe S.]

I think you will be fine with moderate Colt loads. I run 8.0 grains of Unique in my midframe NMBH 45 Colt Flat Top and thats probably the high side of low end but it handles like a champ.

Here is a topic i started on the matter of loads in my gun.

http://www.rugerforum.com/phpBB3/viewtopic.php?f=11&t=199489&p=2004869&e=2004869


Good luck and remember to post pics! Also remember octagon barrels looks RIGHT on mid frame conversions.

 

[DGW1949]

I am considering a OMBH 357, 5" barreled, 6-shot conversion to 45 Colt as a "packin' gun". I know that this frame is NOT suitable for the heavy loads necessary to hunt black rhino, grizzlies and other dangerous game. And, I will have no occasion to hunt these critters or be ambushed by them while walking the farm in Virginia. At the most, I'll have a rare occasion to hunt eastern whitetails. I can see using a ~255 grain bullet running 1100 fps (MAX). Most shots will be fired at paper in a backyard match with friends and family.

I remember reading a column about the different pressure levels of 45 Colt loadings and which frames are suitable for each, but I can't seem to locate it. So … I'm left with a question. Is the OMBH frame OK for moderate 45 Colt loads or should I give up on this as an idea? Any first hand experience that you think is helpful to me as I ponder this choice?

Thanks in advance for your help.

P.S. I have a beautiful 44 Special OMBH conversion already.

As it concerns your converted 3-screw 357 idea,...
It aint the "frame size" that will get ya when using too hot of a load, it's the remaining cylinder wall thickness.
Considering that the time-honored "standard" load of 8.0 Unique over a 250-ish bullet gets less than 850 FPS from most revolvers, I wouldn't go nowhere near 1100 FPS with a 255 bullet....with any powder.
The only exception to that might be if I was to use a newer mid-frame sized cylinder (say from an RNV) which was factory chambered in 45LC instead of reboring my old one. Reason is, those are slightly fatter than an OM 357 cylinder. Even then though, I'd proceed with caution, because any way that you slice it or dice it, ya aint getting a 255 bullet up to 1100 FPS out of a 45LC revolver without venturing into what I would call "+P territory"......and your .45 conversion won't be near as forgiving about that as your 44Spl is.

What I'm getting at here is that if you somehow find a "standard loaded" 45LC to be lacking in the power dept, you'd probably be better off to pick a different gun to hot-rod......Or stick with your .44, which is already about perfect for the uses you stated.

Hope this helped.

DGW

 

[BearBio]

Seems like it would be very little increase in weight, and cheaper, to just get a 45 LC Old Mode.

 

[NewportNewsMike]

......I remember reading a column about the different pressure levels of 45 Colt loadings and which frames are suitable for each, but I can't seem to locate it.

This may be what you remember: https://www.riflemagazine.com/magazine/PDF/HL%20246partial.pdf

 

[contender]

While many folks enjoy owning custom guns to suit their pleasures, I'd have to ask the question of; "why convert one gun to the same configuration as something already offered?"
Ruger made a bunch of OM 45 Colts.
They are 6 shot, and will handle the load you seek.
The 5" bbl can be had by chopping a longer barrel, or you can save money & accept a 4-5/8" factory one.
You would be way ahead in the $$$$ department by just getting a 45 Colt.
Maybe I don't understand your desires?

 

[mhblaw]

I have a Bowen conversion of an OMBH to 45 Colt, 4.75" barrel. Very nice, and with mid-range loads a very good shooter.

 

[Joe S.]

Contender,
I have both, an old model 45 and old model 357. The 357 is a much finer packin piece in my opinion. Also, if you are after a flattop, you will have to convert as the 45 wasnt offered like that.

Personally the way i met my desire for a flattop 45 was buying one of the new model Lipseys models.

 

[Bob Wright]

Ah, the advantage of a Three-Screw ex-.357 Magnum Blackhawk!

The Three Screw .357 Magnum was built on a smaller frame than the .45 Colt, which was built on the same frame as the .44 Magnums. (and .41 Magnum, and .30 Carbine) So with a converted .357 Magnum you get a smaller sixshooter. Small difference, but your hands will know the difference.

Will the frame contain, safely, the .45 Colt? The Colt and others that followed, used that same (almost) sized frame.

Cradle, no fondle, such a custom revolver, and you'll know the diference.

Bob Wright

 

[dlhredfoxx]

IMO, a solution might be to have a 5 shot cylinder made and fit to the gun (and of course a new barrel in .45 cal), to provide for more steel btwn chambers and higher safety margin... and STILL would need to shoot pretty mild loads in it just to be sure. I've seen a 480 runger 5-shot on a mid frame, so surely a 45 Colt could be done the same way... but that's gonna cost some $$$$.

 

[Joe S.]

And make it a 4 shot if carried hammer over an empty...

 

[BearBio]

Ah, the advantage of a Three-Screw ex-.357 Magnum Blackhawk!

The Three Screw .357 Magnum was built on a smaller frame than the .45 Colt, which was built on the same frame as the .44 Magnums. (and .41 Magnum, and .30 Carbine) So with a converted .357 Magnum you get a smaller sixshooter. Small difference, but your hands will know the difference.

Will the frame contain, safely, the .45 Colt? The Colt and others that followed, used that same (almost) sized frame.

Cradle, no fondle, such a custom revolver, and you'll know the diference.

Bob Wright

1. It isn't the frame but the cylinder I would worry about.
2. I have several OM 357's and OM 41 and 45. I beg to differ that my hands "know the difference" although I will admit I like my Lipsy's 44 spl. If that's illogical, so be it!

 

[bogus bill]

I have a number of both calibers in both smiths, colt single actions and a ruger lipsey special. Now if your looking for a excuse for another gun, maybe? Seems I load my .44 specials and .45 colts to the same ballpark level where I doubt I nor any critter can tell the difference. Maybe my handle should be "Wet blanket", but I went through that path about 45 years ago. I own 7 .44 specials and close to that in .45 colts. I also have done several conversions.

 

[DGW1949]

Ah, the advantage of a Three-Screw ex-.357 Magnum Blackhawk!

The Three Screw .357 Magnum was built on a smaller frame than the .45 Colt, which was built on the same frame as the .44 Magnums. (and .41 Magnum, and .30 Carbine) So with a converted .357 Magnum you get a smaller sixshooter. Small difference, but your hands will know the difference.

Will the frame contain, safely, the .45 Colt? The Colt and others that followed, used that same (almost) sized frame.

Cradle, no fondle, such a custom revolver, and you'll know the diference.

Bob Wright

I agree with Mr Wright.
In fact, I've often given thought to having a .45 built on my own OM-357.....which BTW, already wears an even older XR3, Colt (almost) sized, grip frame.
The difference in my wants and those of the OP though, is that I have always been quite pleased with the .45LC as it is, and see no reason to "hot rod" it beyond SAAMI specs.

Once upon a time, someone around here posted pictures of such a conversion which was done by Alan Harton. If I recall correctly, Mr Harton also advised that it be used with SAAMI-spec ammo.....but....I could be wrong about that part. At any rate, maybe that member will see this thread and chime-in with real-world experience and/or offer some real-world loading advice.

DGW

 

[Bob Wright]

O.K. Touche!

The smaller frame will have a correspondingly smaller cylinder, again, approximately the same diameter as the Colt SAA .45. The finished Ruger in.45 Colt will handle somewhat like the Colt revolver. Not exactly, but similiar.

I will differ with you as to handling. My Ruger Super Blackhawk with 5" barrel just feels more massive in my hands than my older .357 Magnums, this in the Three Screw models.

Hamilton Bowen has a photo of a Three Screw .357 Magnum converted to .44 Special and fitted with the New Model steel grip frame from a Fiftieth Anniversary Flat Top, and compares it very favorably to a Colt New Frontier.

Incidentally, when Ruger introduced the Blackhawk in .357 Magnum, advertising of the day stated that it had the heaviest cylinder of any .357 Magnum revolver, so a Three Screw Blackhawk would likely have a larger cylinder than the Colt.

Bob Wright

 

[dwayne]

Thanks, all folks -- from the OP.

Thanks, DGW (and others) -- you are spot on regarding the cylinder vs. frame. Excellent clarification. And, I agree that 1100 fps is out of range for a conversion of this type. Realistically, <950 fps is more like it.

NNMike, thanks. That is the article I remembered. It looks like loads in the Level 2 range would be the limit. Practically, the low side of that range is more realistic. Again, <950 fps with appropriate powder speed.

FWIW, in my opinion (only mine) there is a huge difference between a new Ruger and an old model that has been retrofit, line bored and tuned by a master gunsmith. Frankly, again in my opinion, they are two completely different things; no comparison. And, yep, they ain't cheap. And, I like the size and feel of the OM 357 frame. That's why I am considering the conversion.

Again, thanks all. Your input and genuine perspective is greatly appreciated.

 

[SAJohn]

My 2nd generation SAA's cylinder measures 1.656" diameter and 1.615" in length. My old model .357 flattop Blackhawk measures 1.672" dia. by 1.605" length. I wouldn't consider the differences significant.