I think this is both a reloading question and a general commercial ammo question, so I hope this is the right section in which to post it.

I just acquired a 1914 .455 Triple Lock that has been converted to .45 Colt. This chambering was considered safe enough 80-90 years ago, when I understand that the standard loads for .45 Colt cartridges generated around 10,000-12,000 PSI pressures.

Should I consider that a maximum pressure for any rounds fired through this gun? I figure I would restrict myself to cowboy loads from commercial manufacturers, but when I start reloading is there a safety advantage or an accuracy downside to developing lower-pressure loads?

I'm a complete noob at this, so any information will be helpful. I just don't want to blow up my TL by asking it do something it would never have had to handle in the past. If I'm calculating correctly, from the bottom of the cylinder notch to the inner surface of each chamber there is only .04" of steel. That seems kind of marginal to me. But S&W sanctioned this conversion 90 years ago, and it must have seemed safe enough to them at that time. Away from the notch, cylinder walls seem to be .09". The barrel wall is thinner than that at the muzzle.

Thanks for any advice.

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David Wilson

I don't know what the alloys were in 1914, so absent any hard data, I think you would be wise to limit your handloads to the original ballistics of the 45 LC.

It IS an N frame gun but since it is essentually irreplacable, caution should be in the forefront of your thinking.

David
It has long been understood that factory cast 45 Colt ammo is loaded well below its potential due to the number of old revolvers hanging around in that caliber. I have shot plenty of them in early Colt SAA's with no ill effects. Now that several makers produce the caliber in "cowboy" loads which are even milder, I would say you would be safe with that round and give an even greater margin of comfort. If you reload I would recommend using Hodgdon Trail Boss powder as it is designed as a smokeless alternative to black powder (not a synthetic BP). Winchester 231 or Hodgdon HP38 in small doses would also be suitable.
I meant to mention this on your OP on the gun, but got lazy.

David,
I'm sure you'll get plenty of opinions and advice here from fellow reloaders, but not too many of them have had the chance to work with the TL or any other gun nearing 100 years old, so a bit of extra precaution is in order here.

First, your TL has a cylinder that is approx. .005" - .010" smaller in diameter than a more modern N frame, so that needs to be considered since the locking notch is in the outside wall and is as you noted the weak link, and not just your TL, but in any revolver.
I have been a huge fan of the .45 Colt for a long time and have loaded for a number of them over the last 20-25 years. Everything from mild to extremely wild.

You should try to stick with loads that are running 2-3000 psi under SAAMI spec pressure of 14,000 PSI in your TL.

Alliant Power Pistol is a very good powder for your needs, as is 231, Unique, Red Dot, SR 4756, and Bullseye.

I have been using Power Pistol in my .44 special TL and it works very well indeed. Clean burning and very consistant velocities across the chrono.

Here are a couple of links to powder company websites load data centers-
Cartridge Loads - Hodgdon Reloading Data Center - data.hodgdon.com

Alliant Powder - Home

For your guns fixed sights, the 250 grain lead bullets would be best, since the loads shown in the data will produce velocities very close to the original chambering/bullet weight of the .455, and should regulate to your sights fairly closely.

Try to stick with loads that are running around 12,000 PSI to ensure an extra margin of safety, and durability in your fine old gun. Another reason is that your cylinder is on the short side for the .45 Colt, so you may have to seat bullets a bit deeper than shown. If you do, make sure that you use starting loads only. Most of the bullets shown are within SAAMI specs for cartridge overall length though, and will work as shown. Use components exactly as shown if this is new to you. You don't want any unnecessary problems with pressure.


Edited to add-
Triple Locks did not have heat treated steels until the very end of production of the first model/beginning of the second model, and even then they were just starting to understand the methods of heat treating at the factory, so the steels weren't nearly as strong as later third model steels and post war guns. Their steel was basically the same as those used in earlier blackpowder guns, though at the time they were state of the art alloys. This is the main reason for using caution in a New Century.

Gentlemen, thank you all. That's exactly the mix of reassurance, caution and specific information that I was hoping for.

Once I get rolling with this old cannon I will post a range report.

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David Wilson

Howdy

Current SAAMI max pressure for 45 Colt is 14,000 PSI. This relatively low standard has been adopted because of all the old revolvers still out there. As long as you stay below 14,000 psi you should be fine. The lower you stay, the better for your old Triple Lock.

On a slightly more technical level, Trail Boss was not developed as a Smokeless alternative to Black Powder. Trail Boss was developed as a bulky Smokeless powder to better fill up large cases like the 45 Colt. Cavernous cases like 45 Colt can start to develop consistency problems with light Smokeless charges that leave a lot of air space in the case. So Trail Boss was developed specifically with old, large capacity Black Powder cartridges like 45 Colt in mind. However Trail Boss is a modern Smokeless powder and like all modern Smokeless powders, the pressure spike it develops is very short and sharp, unlike the much more forgiving broad pressure curve developed by Black Powder. The sharp pressure spike of modern Smokeless powders can shock the old steel of some old guns more than the broader pressure curve of Black Powder, even when both powders achieve the same pressure.

A quick look at Hodgon's data for Trail Boss shows maximum pressures between 10,300 PSI and 12,700 PSI for 45 Colt, depending on the weight of the bullet. Well below SAMMI Max for the cartridge, but definitely not Black Powder pressures.

Your Triple Lock was built well into the Smokeless era, so you should not have to limit it to Black Powder loads, as should be done with guns manufactured before the Smokeless era. But the lower you keep the pressure, the better it will be for the gun.

Any loads you find published in a recognized loading manual, or on a powder company's website will be fine, as long as you stay away from the Max. Any loads you find published as 'cowboy loads' will be better.

Amoung others, I shoot 200 gr LRN bullets with 6.5 gr trail boss powder at an advertised 855 fps. It's real mild that is fun to shoot.

Another loading you can look into is the shorter 45 'Schofield' case. It takes some case capacity away and works in most 45 Colt chambers. It's like the 38 spcl/357 mag relationship. There are minor case head differences but usually not an issue. You can go real mild if desired. I use some 'Titegroup' powder in mine.

Most loading manuals have 2 or 3 different power levels. Stick with Level 1 , intended for Colt SAAs. That's what I use for my 1918 Colt New Service , Uberti SAA replicas and S&W 25.

Trail Boss Powder is the answer. It's made exactly for your application.

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Dave

Take a look at the Hodgdon site and Trail Boss powder loads.

My wife cant handle much recoil, she has three rods in her back between her shoulder blades.

I use to load 5.4 grs of 231 pushing a 250 grn cast bullet that she could handle.

I said, USE TO, reasoning. I discovered Trail Boss, light loads that takes up most of the space in the case, meaning for efficient burning and better accuracy..................AND MILD SHOOTING.