??Duplex and Triplex loads?? Am I talking crazy?

[IAM Rand]

Just doing a little research on the vaunted 45 Colt. I kinda feel like I am in a Harry Potter movie when "You know who" was in the forbidden part of the library. (If you have seen a HP movie you will get this.)

Reading an article by Max Prasac, He mentions a triplex load, (two grains of Unique, 25 grains of H2400 and three grains of Bullseye). I can only imagine a witch or wizard standing over a caldron with a stick to stir the smoking brew.

Hunting: The Hard-Hitting .45-Caliber Revolver Cartridges - Gun Digest

Is there a good source on duplex or triplex loads. Not saying that I am brave enough to do this but, just interested in pushing the 45 Colt to its full potential. I have a Governor and a 460 Mag. Was kinda thinking about getting a Henry Big Boy X in 45 Colt. In case the world ends, would a 45 Colt in a Big Boy X be the gun to do it all. Okay you 30-30 fanatics, go away. I know, 30-30 is the do it all but, not sure I would want to shoot a 30-30 in a pistol (says the guy shooting 460 mag out of a 14 inch barrel pistol). Just sayin.

You 30-30 guys can start your own thread.

 

[oldman10mm]

Back in the late 70s' or early 80s' I did duplex loads for 38sp and 357M with 148gr hollow base wadcutters (LOADED BACKWARDS) for in a M19. Results were excellent, velocities generated resulted in extreme expansion. never had case expansion or blown primer.
Testing was discontinued because of all the new expanding factory hollow point ammo coming out at the time (40 years ago).

 

[TexasViking]

.357 Mag rather than .45 Colt, but one of the last articles I did for the Western Powders emag was a Triplex I called the .357 Triple Ought. Something its editor, Rob Behr really wanted me to do after I mentioned that I thought it was doable with 000 buckshot. I used Ramshot True Blue that should work very well for the Colt as well, or something similar in burn rate, and more importantly, volume req'd. Years ago, the discontinued W630 was a top choice which True Blue is close enough too. Flake powders can be used as well. In the SPEER #11, they used a good variety of different powders for their shot capsule loads, and there are some similarities in powder charge requirement.
I made wads out of thin plastic by cutting them out of cheap plastic containers using a sharpened case using a chamfer/deburring tool. Only problem I ran into was that True Blue is so fine grained it would slip past the plastic wad. Solved that by placing a thin cardboard wad below the plastic.
Velocity was around 800 FPS, and at 7 yards the patterns were tight enough to impress.
You might also check for molds that essentially make discs, if the lead discs can't be found. Wiley Clapp did something similar some years ago, but I don't remember the caliber. Might have been duplex in .38 Special.

 

[ruggyh]

Powder selection has come a long way since duplex and triplex loads where the attempt to get the last bit of velocity out of a cartridge.

Would love to know how many revolvers were lost in the attempts to break the 2000 fps barrier (with 300 grain bullet) in the development of the 454 Casull.

It should be noted that true duplex and triplex loads were about layering powders not mixing them.

I would add here that if you do pressure testing on handgun cartridges you will note that peak pressure is reached while the bullet is still in the brass, and this should help you understand the folly of the practice in general.

 

[TexasViking]

Powder selection has come a long way since duplex and triplex loads where the attempt to get the last bit of velocity out of a cartridge.

Would love to know how many revolvers were lost in the attempts to break the 200 fps barrier (with 300 grain bullet) in the development of the 454 Casull.

It should be noted that true duplex and triplex loads were about layering powders not mixing them.

Duplex/Triplex in terms of powder charges? Glad I saw your post, because like oldman10mm, I though the op was wanting to make a multiple projectile load. Not sure that duplex powder charges were ever a good idea, and I haven't heard of a sane man using 3 different powders in any handgun handload.

 

[LoboGunLeather]

Ammunition manufacturers sometimes use blended powders, but they have full ballistic laboratory facilities to guide them in these efforts.

Most of us rely on published data from reputable sources. A few intrepid souls play around the upper edges of the envelope. Personally, I am happy with reloads in the 90% range of "possible" performance, and if I think more power is necessary I choose another gun and caliber for the purpose.

I've been doing this for 50 years and it has worked very well for me. All of my firearms remain in one piece, both eyes still in my head, etc.

 

[2152hq]

I'm not aware of any Duplex or Triplex published loading charts/info.
There are a few loads here and there for a few calibers (rifle). Ackleys 1st volume (?) handloading has some info and duplex loads for 458, maybe others.
Elmer K and one of his gun buds C.M.O'Neill experimented with duplex loads using a primer tube for front ignition.
I think O'Neil actually got a patent on the front ignition primer tube.
This was in the mid 30's
The idea was that the fast burning powder was loaded first into the case and was at the bottom of the stack.
The slow burner on top of that.

The front ignition set off the slow burning powder first and the charge consumed itself burning back to the fast burn powder which was used up as the bullet neared the muzzle of the bbl.
So the bullet got an extra HV kick so to speak as the slow burning powder was being used up.
All theory, though EK claimed great success.
Later lab tests on the loads showed little or no difference to regular loadings.

Triplex is really getting into unkn territory. 3 different powders laying hopefully in nice even layers AND staying in that possition after loading. Handling, transportation, and other things not eventually mixing the powders at all to cause a 4th powder,,a uneven mix of the 3.

There was a book published by Wolff Publishing (Rifle and Handloader magazines) in the late 80's or early 90's.
The book was 'Gibbs Cartridges and Front Loading Techniques'.

It's still available from a few sources I imagine.

These were the experiments of 'Rocky Gibbs' the cartridge wildcatter and experimenter, rifle builder.

(Not the George Gibbs Rifle Co of Bristol, England nor the
Navy Arms side company Gibbs Rifle Co' of the 80's/90's)

Likely some interesting info in there, but I'm sure all rifle data if any and probably for his extensive like of 'Gibbs Magnum' cartridges.

My gut feeling is that what ever extra vel advantage you feel may be approachable by duplex or triplex loads is likely already there with careful single powder loads and factory data.
Gaining an extra few FPS has always seemed to be the supreme accomplishment for many in handloading.
Personally I don't see why, but everyone has their own reason for doing stuff.

Mixing powders as always been near the top of the Things Not to do when Handloading.

 

[Nevada Ed]

I thought this might be about shotgun loads, but see that I was wrong.

Mixing powders ?

Who is going to test out your loads, for you ?

I think I will pass on this one,

 

[IAM Rand]

Initially I thought that it was a dump and shake process but, am learning that it is a layered process(cake/icing/cake/icing). TexasViking had kinda answered that question of how do you keep the layers separate. Sound like a little more work that it is worth. I am assuming that this is more of a pistol cartridge process than a rifle. Curiosity more that planning. Was just reading the article and was interested to see if someone was still dabbling in these dark arts.

 

[max]

I believe this is how Richard Casull started playing around with the 454. I see no reason to even think about such a thing. Even Elmer thought it was a witch's brew.

 

[Rpg]

I recall reading about these loads in the late '60s.

They were touted as squeezing the most out of the cartridge, however the very few published ballistics seemed to represent only trivial differences with published numbers for the corresponding factory loaded ammo.

In other words, you could improve on factory ammo. Of course, you could do that with many published loads using just one powder, so using two or three didn't offer anything.

As I recall, the articles seemed more about a technique than about noticeable benefits resulting from the technique.

 

[TexasViking]

I believe this is how Richard Casull started playing around with the 454. I see no reason to even think about such a thing. Even Elmer thought it was a witch's brew.

Yep, Dick Casull, and IIRC, the very fast powder he used for enhancement was Red Dot, maybe Bullseye as well.

Don't know how he got SAAMI to allow a Max Average Pressure of 65,000 PSI. That's as high as it gets for common magnum rifle cartridges and the .270 WIN.

Just goes to show that if enough people wanna buy something, someone will make it. Not that I wouldn't own a .454 Casull revolver, but for the field it would be loaded like 30,000 PSI Colt loads with either case.

 

[STORMINORMAN]

If you have a 460 S&W and can shoot 45 Colt, "Ruger (etc.) ONLY" & 454 Casull loads why would one wish to venture into Triplex loadings?

What bullet weight and velocity is not already available?

Jus' askin'...?

Cheers!

P.S. There are rifles chambered in 454 Casull, BTW...

 

[ruggyh]

Initially I thought that it was a dump and shake process but, am learning that it is a layered process(cake/icing/cake/icing). ... Sound like a little more work that it is worth. I am assuming that this is more of a pistol cartridge process than a rifle. ....

Actually the process would theoretically be of some benefit in rifle large cartridges as the layered power(s) would come into play after the bullet has left the cartridge and have a much greater of volume to inhibit excessive pressure - though secondary pressure wave might create additional unwanted barrel harmonics.

Ammunition manufacturers sometimes use blended powders, but they have full ballistic laboratory facilities to guide them in these efforts.....

Blending powders and duplex loading are not the same thing.

Powder blends are homogeneous mixture of two powders.

Duplex loads are layered powers.

In today's world munitions manufactures can order powers to their specifications and there is little need to play with blending powders, they are not restricted to canister powders used by the the reloading community.

 

[Cdog]

I've seen results of duplex plus loads. Chronograph doesn't lie. A fellow I went to high school with married into a true loading Dr. Frankenstien family. He and his father in law achieved velocities with handguns that no rifle length barrel could match.

They were very tight lipped. Each time the subject of load data came up they may smile a bit, but you got nothing from either of them.

I have no interest in trying it, but the curiosity is still there.

 

[GypsmJim]

Yes you are talking crazy. Show me a published reference loading manual that shows the data. What would be the purpose anyway? Faster velocity, cleaner kill, talking rights?

This is without doubt the dumbest thread I ever read.

 

[TexasViking]

I've seen results of duplex plus loads. Chronograph doesn't lie. A fellow I went to high school with married into a true loading Dr. Frankenstien family. He and his father in law achieved velocities with handguns that no rifle length barrel could match.

They were very tight lipped. Each time the subject of load data came up they may smile a bit, but you got nothing from either of them.

I have no interest in trying it, but the curiosity is still there.

And you remember the story about what curiosity did to the cat? LOL!

 

[ruggyh]

I've seen results of duplex plus loads. Chronograph doesn't lie. A fellow I went to high school with married into a true loading Dr. Frankenstien family. He and his father in law achieved velocities with handguns that no rifle length barrel could match.....

What you need to see is the pressure data !!!!!

 

[DWalt]

COTW gave a triplex load for the .454 Casull in earlier editions, but later editions went back to single propellant loads only using H110, 2400, and 296 respectively for 250, 260, and 300 gr JHP bullets. Large Rifle primers were recommended. Unique was recommended for use with lighter 200 and 225 gr JHP bullets.

I can't think of a single reason that I would ever buy a .454 Casull revolver.

 

[ruggyh]

Internal ballistics are well studied and all the mathematics were well established in the relatively early in the 1900's.

Here is a list reading material/references that will help you better understand what is happening once the primer is ignited.

Once you start to understand the basics you should be able to see the limitations of concepts like duplex loads, primer extension tubes and the numerous other experiments that individuals concoct.

If any of these really were reasonable successful the would be common in the market place.

"Interior Ballistics of Guns" Engineering Design Handbook Gun Series, AMCP 706-150, 1965
This is a more serious effort and is on a par with Hunt's "Internal Ballistics" i. The experimental methods described date from the WWII. This is available online

F. R. W. Hunt "Internal Ballistics" The Philosophical Library, 1951
An edited collection of contributions by a number of British ballisticians. It goes into the basic theory of internal ballistics with a good description of the experimental work and methods. This is available online

J. Corner "The Theory of the Interior Ballistics of Guns" Wiley, 1950
The "classic" text on the theory of internal ballistics. A statement of the state of the art in British research at the end of WWII. This is available online.= a must for students of internal ballistics bookshelf

If you are interested in an expanded list PM me