45 Colt Load OK For 25-15?

A S&W 45 ACP cylinder is the same OD as a 45 colt cylinder, the stop notches are in the same location. They will both contain the same pressure. As far as the frame goes it is the exact same frame as the model 29. The 45 colt does have a larger volume. The SAMII standard is because they have to consider all the nearly 150 year old colt revolvers in 45 colt. NOT because of any weakness in modern S&W revolvers chambered for it.

I limit my rounds to pressures under 25,000 psi, or 1,100 fps with a 255 gr SWC another 100-200fps will not change the 100 yard trajectory much and as they will go all the way though something like an elk the extra velocity will not kill anything any deader. I have 8 S&W 45 colt revolvers and none of them have had a single problem. I do not, however, fire warm loads in my 455 Triplelock which was reamed to 45 colt out of respect for its 100+ life

S&W 45 colt love

This one was made up from a 5 screw HP frame, a 45 colt barrel and a recessed 44 mag cylinder reamed to 45 colt. A 5 screw pinned and recessed 45 colt
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another 5 screw pinned and recessed 45 colt, this onbe made up using a 1955 frame and barrel
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On this one I used a 1917 frame and a 1950 barrel and a 25-5 cylinder
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this one started life as a Brazilian
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both of these were originally 629-1s
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this one was an 8 3/8" 25-5 when I got it. Now a 5" pinned and recessed
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this 455 TL had been converted to 45 colt by the reaming and partially recessed method when I found it
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Ruger only loads. Ruger 45 cylinders are the same diameter as S&W cylinders, but they have a slight advantage in that their stop notch is slightly off center of the chamber.
 
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...I've always wondered is how is the mod 25 frame different than the mod 29 that takes far more aggressive pressure in stride... John

It's the cylinder, specifically the stop/lock notch thickness, you need to be concerned with first in this comparison.

At it's thinnest point the cylinder lock notch of a S&W 45 revolver (either 45ACP or 45 Colt) averages .030" thick (outside chamber wall thickness minus the lock notch's depth).

On a S&W 44 Magnum it averages .040" thickness.

That's ~25% less in metal thickness for the 45 to contain the chamber pressures.

.
 
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"A S&W 45 ACP cylinder is the same OD as a 45 colt cylinder, the stop notches are in the same location. They will both contain the same pressure. As far as the frame goes it is the exact same frame as the model 29. The 45 colt does have a larger volume. The SAMII standard is because they have to consider all the nearly 150 year old colt revolvers in 45 colt. NOT because of any weakness in modern S&W revolvers chambered for it."


"Originally Posted by Arkfarmer ...I've always wondered is how is the mod 25 frame different than the mod 29 that takes far more aggressive pressure in stride... John
It's the cylinder, specially the stop/lock notch thickness, you need to be concerned with first in this comparison."

"At it's thinnest point the cylinder lock notch of a S&W 45 revolver (either 45ACP or 45 Colt) averages .030" thick (outside chamber wall thickness minus the lock notch's depth).

On a S&W 44 Magnum it averages .040" thickness.

That's ~25% less in metal thickness for the 45 to contain the chamber pressures."


Interesting. Makes sense that an N frame, is an N frame, is an N frame be it .357, .41 Mag, .44 Spec, .44 Mag or the .45's. Is the cylinder window the same size for all N frames? Is the cylinder diameter the same for all N Frames? If the diameter is the same I assume notch location and timing are the same?
 
if we were talking some 20 some odd grains of 2400, we might have some debate. but what you have there in something in the realm of a standard issue target load.
 
A few years ago I lucked into a Colt Model 1909 U.S. Army in .45 Colt. This revolver is 114 years old and I shoot it regularly. While reading up on it's history, I found the War Department's specifications for the ammo. They required a round with a 250 grain bullet at 750 FPS. Using a computer program a friend has, we found about 30 different loads of various powders that gave us that velocity. My favorite is 5.6 grains of Bullseye and it shoots that to point of aim at 25 yards. Also for you folks that like Unique the load is 6.4 grains.

I figure since these revolvers were being used in the Philippines against Moros (who were rather fanatical and .38 Special was not stopping), then it should be good for me. Good target load and defense load all rolled into one. Besides it does not beat up the gun or you to shoot it.

I figured if we are going to talk history we should get it correct. It wasn't the .38 Special that failed. I'm fairly sure it was the 38 Colt or 38 S&W.

Also, while they were fanatical if was being drugged up which kept them coming after being shot.
 
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I figured if we are going to talk history we should get it correct. It wasn't the .38 Special that failed. I'm fairly sure it was the 38 Colt or 38 S&W.

Also, while they were fanatical if was being drugged up which kept them coming after being shot.

It was the 38 Colt cartridge that was not good at stopping them. Of course, neither was the 30-40 and even the 45 long Colt had some issues. It was just a matter of which one had fewer issues.

Kevin
 
I figured if we are going to talk history we should get it correct. It wasn't the .38 Special that failed. I'm fairly sure it was the 38 Colt or 38 S&W.

Also, while they were fanatical if was being drugged up which kept them coming after being shot.

Sorry, fingers are not use to typing 38 Colt. It has been around since 1898, so I guess it was to experimental for the military to use it yet

It was the 38 Colt cartridge that was not good at stopping them. Of course, neither was the 30-40 and even the 45 long Colt had some issues. It was just a matter of which one had fewer issues.

Kevin

Yes, it was the .38 Colt. Both the .38 Colt and the 30-40 Krag were having problems. So, they dusted off the Colt SAA's in .45 Colt. These worked better. The pistol that was to become the M1911 was being developed. By 1909 the Colt SAA's were wearing out and the War Department need a replacement until the M1911's came on line. So 30,000 Colt M1909 U.S. Army's were procured. Almost all of these were sent to the Philippines.
 
My standard load for the .45 Colt has always been 9 grains of Unique under a swaged Remington 250-grain RNFP. I shot these for many years through a Ruger Blackhawk and a Colt Anaconda. I wonder if this is OK in my new 25-15 or should I drop the powder weight a couple grains? I did put a cylinder's worth of these cartridges through it and found that my crimp needed to be heavier to keep the bullet from backing out, a problem I never had with the other two guns. I think part of it might be that the Smith is lighter and recoil is snappier. Shooting the 25-15 is a pleasure and I don't want to stress it.
Sounds like you have already correctly diagnosed the issue. Not enough crimp for this load in the lighter gun.
Pretty easy fix. Too bad all reloading issues aren't that easy to remedy, eh? :D
 
"A S&W 45 ACP cylinder is the same OD as a 45 colt cylinder, the stop notches are in the same location. They will both contain the same pressure. As far as the frame goes it is the exact same frame as the model 29. The 45 colt does have a larger volume. The SAMII standard is because they have to consider all the nearly 150 year old colt revolvers in 45 colt. NOT because of any weakness in modern S&W revolvers chambered for it."


"Originally Posted by Arkfarmer ...I've always wondered is how is the mod 25 frame different than the mod 29 that takes far more aggressive pressure in stride... John
It's the cylinder, specially the stop/lock notch thickness, you need to be concerned with first in this comparison."

"At it's thinnest point the cylinder lock notch of a S&W 45 revolver (either 45ACP or 45 Colt) averages .030" thick (outside chamber wall thickness minus the lock notch's depth).

On a S&W 44 Magnum it averages .040" thickness.

That's ~25% less in metal thickness for the 45 to contain the chamber pressures."


Interesting. Makes sense that an N frame, is an N frame, is an N frame be it .357, .41 Mag, .44 Spec, .44 Mag or the .45's. Is the cylinder window the same size for all N frames? Is the cylinder diameter the same for all N Frames? If the diameter is the same I assume notch location and timing are the same?

Yes, the cylinder window is the same on all N frames and the cylinders are all the same diameter. The 357, 44 special, as well as the 25-3 and earlier 45 colts are all about 1/8" shorter than the 41 and 44 mag and 45 colt cylinders from 25-5 and later. The 45 acp cylinders are the same 1/8" shorter in front as well as about .035 shorter to the rear for the clips. The 357, 44 special, 45 acp and early 45 colts guns all have an 1/8" longer barrel extension to close up the B/C gap using their shorter cylinders. The stop notch and ratchet are all the same. The 45 acp cylinders have a thicker ratchet to head space properly with the clips. The ends of the extractor arms changed when the pins were deleted and the stop notch got longer with the addition of the endurance package. (See note below on endurance cylinders)

I have fit a pre model Highway patrolmen with a 45 colt cylinder made from a 29-2. I have also made 45 colt cylinders using 357 cylinders. I have also fit a 25-5 cylinder to a 1917 frame. While the overall shape of the ratchet teeth changed over the years, the shape of the surface engaged by the hand remains the same.

The metallurgy and heat treatment of the cylinders and frame no doubt improved as time went on. But, I find it extremely hard to believe that it makes any economic sense that any of the frames or cylinders of the same era got a better metal or treatment than the others. From a production tracking and liability standpoint it would be huge minus to do otherwise.

While I would not make a triple lock or early 1917 frame into a 44 magnum, I have made a 1917 into 45 colt and fired plenty of 255 gr- 1100fps rounds though it using more recent cylinders. It is the cylinder that fails not the frame and the cylinder will fail long before a load causes the frame to stretch.

Look at the old cap and ball colt dragoons that fired appox the same sized bullet at 1000fps with no top strap what so ever.

45 colt vs 44 mag cylinder wall and notch. The OD of the 45 colt case is .480 and the 44 mag is .457. A difference of .023 in diameter and .0115 in radius meaning the entire outside cylinder wall is that much thinner as well as the stop notch. The 44 mag runs at 36,000 psi a 45 colt at 25,000 psi has 30% less pressure. The stop notch cylinder area of 45 colt is exactly the same as that of a 45acp cylinder that is OKed for 23,00 psi 45ACP +P.

BTW go look at the thickness of the chamber wall on a 1911 running 45 supers at 28,000 psi. Then know a lot of guys are shooting a lot of 45 supers from 25-2s


One more note is that the endurance package and later cylinders had a longer stop notch and cylinder stop. It is located in the same spot as the previous guns. A endurance cylinder will work n a non endurance frame. But, a non endurance cylinder will not work correctly in an endurance frame with an endurance stop. Also in my opinion from an engineering stand point the endurance cylinders are weaker than the non endurance ones. Because the stop notch is longer you have a larger amount weaker area in a critical area of the chamber wall. If you do not believe that making the notch longer makes them weaker I advice you NOT to make the notch cut on a chamber full length and fire a round in it. A small thin spot in a pressure vessel get more support from the surrounding thicker area than a wider OR LONGER one

I spent 2 months earlier this year supervising the inspection and pressure testing tube exchangers. Worked with several API inspectors and 4 people who checked tube corrosion and wear using equipment that I will call sonic waves to get readings along the length of the tubes and another method called an iris that uses a small camera to visually record the condition of each tube. If tubes are suitable for continued use id determine by not just dept of corrosion but by area of corrosion and the amount of linear corrosion will cause rejection faster than radial.
 
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OP hasn't been back for about 3 months, but if he returns:

Is the 9 gr Unique/250 gr load accurate in your model 25?
Have you tried lighter loads for accuracy?
Do you need the heavier load or is it just for paper punching? If the latter, why not try a lighter load?
 
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Yes, the cylinder window is the same on all N frames and the cylinders are all the same diameter. The 357, 44 special, as well as the 25-3 and earlier 45 colts are all about 1/8" shorter than the 41 and 44 mag and 45 colt cylinders from 25-5 and later. The 45 acp cylinders are the same 1/8" shorter in front as well as about .035 shorter to the rear for the clips. The 357, 44 special, 45 acp and early 45 colts guns all have an 1/8" longer barrel extension to close up the B/C gap using their shorter cylinders. The stop notch and ratchet are all the same. The 45 acp cylinders have a thicker ratchet to head space properly with the clips. The ends of the extractor arms changed when the pins were deleted and the stop notch got longer with the addition of the endurance package. (See note below on endurance cylinders)

I have fit a pre model Highway patrolmen with a 45 colt cylinder made from a 29-2. I have also made 45 colt cylinders using 357 cylinders. I have also fit a 25-5 cylinder to a 1917 frame. While the overall shape of the ratchet teeth changed over the years, the shape of the surface engaged by the hand remains the same.

The metallurgy and heat treatment of the cylinders and frame no doubt improved as time went on. But, I find it extremely hard to believe that it makes any economic sense that any of the frames or cylinders of the same era got a better metal or treatment than the others. From a production tracking and liability standpoint it would be huge minus to do otherwise.

While I would not make a triple lock or early 1917 frame into a 44 magnum, I have made a 1917 into 45 colt and fired plenty of 255 gr- 1100fps rounds though it using more recent cylinders. It is the cylinder that fails not the frame and the cylinder will fail long before a load causes the frame to stretch.

Look at the old cap and ball colt dragoons that fired appox the same sized bullet at 1000fps with no back strap what so ever.

45 colt vs 44 mag cylinder wall and notch. The OD of the 45 colt case is .480 and the 44 mag is .457. A difference of .023 in diameter and .0115 in radius meaning the entire outside cylinder wall is that much thinner as well as the stop notch. The 44 mag runs at 36,000 psi a 45 colt at 25,000 psi has 30% less pressure. The stop notch cylinder area of 45 colt is exactly the same as that of a 45acp cylinder that is OKed for 23,00 psi 45ACP +P.

BTW go look at the thickness of the chamber wall on a 1911 running 45 supers at 28,000 psi. Then know a lot of guys are shooting a lot of 45 supers from 25-2s


One more note is that the endurance package and later cylinders had a longer stop notch and cylinder stop. It is located in the same spot as the previous guns. A endurance cylinder will work n a non endurance frame. But, a non endurance cylinder will not work correctly in an endurance frame with an endurance stop. Also in my opinion from an engineering stand point the endurance cylinders are weaker than the non endurance ones. Because the stop notch is longer you have a larger amount weaker area in a critical area of the chamber wall. If you do not believe that making the notch longer makes them weaker I advice you NOT to make the notch cut on a chamber full length and fire a round in it. A small thin spot in a pressure vessel get more support from the surrounding thicker area than a wider OR LONGER one

I spent 2 months earlier this year supervising the inspection and pressure testing tube exchangers. Worked with several API inspectors and 4 people who checked tube corrosion and wear using equipment that I will call sonic waves to get readings along the length of the tubes and another method called an iris that uses a small camera to visually record the condition of each tube. If tubes are suitable for continued use id determine by not just dept of corrosion but by area of corrosion and the amount of linear corrosion will cause rejection faster than radial.

One minor point - I think you meant "no TOP strap whatsoever" didn't you?

As always a very detailed, knowledgeable, and informative technical post steelslaver
 
Topstraps, bootstraps & backstraps (Yum!)...?

It truly was a very detailed, knowledgeable & informative post!

Cheers!
 
Ah yes, boiler tubes.

While I have done boilers, mostly I do exchangers. Most boilers only go up to 600psi and lots of exchangers go well over that

Most piping except for maybe some hydraulic stuff does not reach the pressures of gun chambers. But, pipes and tubes fail in the same manner and for the same causes that a chamber fails. Over pressuring the weakest spot. This is especially true with gas and vapor lines.

A failure in a decent sized boiler tube can look a lot like a failed chamber. Getting to it so you can chop out the ruptured section enough to extract it can be a major pain. Failures in the super heater section of a furnace can also be "interesting"

The open area in this picture is where a 600# boiler in an Algerian LNG plant that failed was located. Not only is nothing there, look at the damage done to the nearby structures. 27 dead and 70 some injured. Some of the dead were totally vaporized.

To those working in live refineries and similar plants a chamber failure is only very small release.

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As always steelslaver excellent information. Exactly what I wanted to know! One more question if I may; on your M28 conversions to .45 Colt did you re-bore the .357 barrels or???
 
Thanks StrawHat what I needed to know. I might see If JES re-boring will do that work. If it will clock correctly to the frame after the re-bore I could get the hand tools//pilots to cut the extension back and redo the forcing cone and crown.
 
S&W cylinders are proofed the same regardless of caliber so don't let anyone tell you S&W uses an inferior steel or tempering for one cylinder versus the other. It would be MORE expensive to do something so foolish than to run all cylinders through the same hardening and tempering process. All N frames have the same cylinder diameter and the charge holes for the .45 Colt are just 0.5mm larger by radius which is nearly inconsequential.

The Model 25-15 uses the long, slender, tapered barrel which creates an illusion of lightness and weak construction, and certainly recoil will be greater due to lighter weight. Can the gun handle modern .45 Colt and .45 ACP level loads? Absolutely and then some. The M 25-15 can take the same stout loads as earlier models, or other brands, but you don't want to shoot them because the recoil is much more aggressive. Despite perception, any standard .45 Colt load up to 900fps with a 255 grain bullet or equivalent is perfectly safe, it's just going to let you know it's a top load.
 
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