Black powder duplex loads?

[Hang Fire]

I have been reading on black powder loads for accuracy in single shot rifles and come across some records being shot around turn of 20th century with duplex loads. From what I gather, the load consisted of about 3 grains of early smokeless under the black powder. Was this for improving load or does it burn cleaner? Does anyone shoot such loads today?

[RMulhern]

Oh..I'm certain others do it! Just like 'others' that stick 45 grs. of smokeless in a case 2.4" long DESIGNED FOR BLACKPOWDER and then gripe that "My rifle won't shoot!"

[Chill Wills]

Black powder duplex loads?
I do not use them for much anymore but there are many reasons to learn about them by shooting them.
There is no shortage of controversy about this subject but the best way would be to try it and have your own experience.
Moreover, there is LOTs of data out there, read all you want, you won't run out.
A few grains of SR-4759 would be a great way to start.
One of the big things it can do is turn poor powder into OK or even really great shooting powder and as you have noted it shoots very clean.

And, on and on....... Buckle your seat belt and read what comes next!

[John Boy]

Does anyone shoot such loads today?

Hang Fire, yes I shoot duplex BP reloads but a little history first: The match shooters around the turn of the century used a different 'smokeless' powder as we know it today. That 'smokeless' powder was Dupont's Lesmok and Kings Powder which both were semi smokeless powder with charcoal mixed with nitrocellulose , sulfur and potassium nitrate.
This duplex's purpose was to increase the velocity for reloads used in matches, specifically 200yd Schuetzen matches. These shooters also used straight semi smokeless rounds
Later on, real smokeless came into being such as Lightning that was pure nitrocellulose based and the use of duplex and semi smokeless rounds waned going up into the 1930's. Remington factory semi smokeless Lesmok ceased around pre- WWII. Kings semi smokeless in the early 1930's IIRC. I have a box of Remington 22lr rounds that have a 1939 birth date

OK, as for duplexing the rule is: use a smokeless powder that by its self does not generate a pressure for a given charge & bullet weight greater than the SAMMI MAXIMUM pressure for that caliber using straight black powder. Then use 5 -10% smokeless of the black powder charge and reduce the black powder by that 5-10% ... dependent on the smokeless powder psi or CUP

The warning caveat: Duplexing with real smokeless powder on the market today is not recommended for any reloader unless they have substantial smokeless powder internal ballistics knowledge for the powder that is intended to be used

[OuchHot!]

The knowledge base today is quite a bit better developed than what was available decades ago. I recall using such duplex loads to get better ignition and cleaner burning in BPCR. Over time, I found that correct primer selection and modest compression of the BP eliminated any need for such duplex loading. I have shot quite a few shots in BPCR with no problem and great accuracy without the crutch of duplex loading. At this point in time, I cannot say that the duplex load was needed but merely a symptom of my lack of know how. Maybe the BP today is simply better? I don't know. I haven't shot a duplex PB/smokeless in maybe 30yrs and see no reason to do so now.

[JeffinNZ]

My Martini Cadet LOVES a duplex load of 3.7gr of H4227 under 13gr of Swiss 3Fg. Burns so clean the bore is shiny after firing.

[45 2.1]

Oh..I'm certain others do it! Just like 'others' that stick 45 grs. of smokeless in a case 2.4" long DESIGNED FOR BLACKPOWDER and then gripe that "My rifle won't shoot!"

If you study the history your trying to duplicate. You would find that the early leaders of long range accuracy actually tried and used triplex loads of different granulations of blackpowder. All of them used new technology to increase accuracy and ease of shooting. None of them went backwards................

[frnkeore]

I've shot duplex loads since '86 and shot my last duplexed load at the end of October of this year. I came to single shots from round ball muzzle loaders in '85 so, it was a natural thing for me to shoot BP. At that time all that was available was GOEX and in group buys, it was $5 a pound.

The world famous Rowland group was shot with a duplex load and very few shooters have equaled or beat that group even 100+ years later with the finest smokeless powders available today.

At the turn of the century most match shooters used either Bulk Schuetzen or seived (using the FFG size granuals) Bulk Shot Gun powder in there duplex loads. Some even used the smokeless on top of the black powder, with claims the the black ignited better. In all cases that I've read about it was to keep the BP fouling down. The newer BP's I'm sure are better than the older stuff but, it still fouls. Most guys that use blow tubes would rather wipe between shots if they had the time aloted for it. I've also shot slug guns and the wiping has to be kept the same from shot to shot but, you shoot on a clean bore and I will venture to say that NO other way is as good. I also tried duplex with my slug gun (not legal) and had good results (not as good as wiping) w/o wiping the barrel for 3 - 5 sighters and 10 record shots.

Now for my personal experiance........... These are the rifles that I've shot duplex,

44 Stevens, 32/40, both fixed and breech seated.
Ballard 32/40, BSed
Win HW, 32/40, BSed
Clerke HW, 32/40, BSed
44 1/2 Stevens, 32/35, BSed
Hoch, 32/35, BSed
Sharps Borchardt, 45/70, BSed

I use no less than 10% and no more than 15% smokeless in my loads, you also still need a good lube. Darr lube is ok, Emmert maybe better, I use my own mix, but can't say that it's better than some others as long as they keep the fouling some what soft.

You can use the 10 - 15% with any powder in the 4759 - H110 burn rate, safely. I've not tried the newr powders but, if you use GOEX, use only FG, FFG is not as accurate in my testing, because of the fines in it, I guess.

BSed, you can get the velocity over 1500 fps with full case charges so, I mostly use 4759 to take up space so, there is less BP to increase velocity. My only formula is that I use smokeless by weight and BP by bulk. That so the smokeless is well controled. I've toped the charge with both a grease wad and solid and I believe the solid wad has a advantage but, only a little. I also use heavier tapered bullets and I don't think you'll get as good of results with lighter bullets (like 165 gr 32's). My fixed 32/40 loads for the 44 are 319247, 165's but, they were only to see what a orginal gun would do loaded with all original stuff. #6 loading tool, Lyman sights and all.

These are my best 5 shot groups, shot in competion at 200 yards in back to back years, I believe my highest score target was a 243 all shot with scopes. My best iron sight score was 237.

Frank

[kokomokid]

45 2.1 Do you have any reference material on duplex or triplex of black powder (no smokeless). I have tried a small charge of 3f below 1.5f and 1f without much sucess? THANKS LB

[45 2.1]

The world famous Rowland group was shot with a duplex load and very few shooters have equaled of beat that group even 100+ years later with the finest smokeless powders available today. Frank

Rowlands group was a machine rest one, not hand held. It has been beaten in competition by handheld SS smokeless powder rifles. Pope said he shot an equal to it handheld in practise, but he reported he lost it to the wind while gathering equipment.

45 2.1 Do you have any reference material on duplex or triplex of black powder (no smokeless). I have tried a small charge of 3f below 1.5f and 1f without much sucess? THANKS LB

I read the triplex add in a pre 1900 periodical. Duplexing with 4f in back of coarser BP was common and in some cases slower BP was behind faster BP. They had a much greater choice in BP as well as the English powders. One would have to search the old shooting magazines of that era to find more.

[Ed in North Texas]

Paul Mathews had information on duplex loads in several of his books. And, I seem to recall that the Canadian "Victorian" (Snider and Martini-Henry, probably among others) rifle competition allows duplex loads in their competitive matches.

[twildman]

If you can dig up Ned Robert's articles from the 1930s in the American Rifleman, you will find that he made extensive use of duplex loadings in BP calibers, from small to very large. I seem to recall mention made by him of "NUmber 80", which, if I recall, was the predecessor of 4759.

[twildman]

Sorry, that is Ned Roberts's articles....grammar, ya know..

[Chill Wills]

[QUOTE=45 2.1;1511989]Rowlands group was a machine rest one, not hand held.
I grew up with in eye shot of Rowland’s old place at the mouth of Eldorado Canyon. No place in Colorado does the wind blow harder and gust higher. Wicked nasty place.

I forgot half or most of what I think I know about Rowland. 45 2.1, if it was NOT shot with front rest, barrel in roller shoe clamp and rear bags I am not sure what it is you mean. Maybe we are talking about the same thing.
I do know that Roland did not shoot all the shots in his record group on one day but returning day after day choosing conditions to shoot only when he felt he could be sure he was safely in the same condition.

Duplex were legal and used by a majority of competitors in the NRA (US) National Championships for Creedmoor and Midrange until about 2003
Duplex works and works well. It just is not as pure as All black….

[45 2.1]

I forgot half or most of what I think I know about Rowland. 45 2.1, if it was NOT shot with front rest, barrel in roller shoe clamp and rear bags I am not sure what it is you mean. Maybe we are talking about the same thing.

Not according to Rowlands account. A machine rest held the rifle. All the shooter had to do was put his hand behind the buttplate and pull the trigger. Read Rowlands account as that is what he said about it............

[wgr]

Paul Matthews says that for every grain of smokeless powder used it is like using 3 grains of black

[RMulhern]

If you study the history your trying to duplicate. You would find that the early leaders of long range accuracy actually tried and used triplex loads of different granulations of blackpowder. All of them used new technology to increase accuracy and ease of shooting. None of them went backwards................

Thank you....I've studied the history now for around 50 years or so! But you see...I'm one of the OGANT......and don't care to do everything the 'easy way'!

[montana_charlie]

Sorry, that is Ned Roberts's articles....grammar, ya know..

I'm happy that grammar is important to you.
But, when the word ends in 's', you don't need the second 's'.

Example: Ned Roberts' articles ...

[twildman]

I'm happy that grammar is important to you.
But, when the word ends in 's', you don't need the second 's'.

Example: Ned Roberts' articles ...

bloody complicated language; next I will leave participles dangling....

Anyway, I had success in my Trapdoor with 5 grn 4759, balance Goex Ctg. black, lightly compressed. No enlarged flash holes or magnum primers were needed, and the bore did not foul up from shot to shot. I stopped using it so as to not have to scrub a 125-year-old barrel any more than necessary, and stuck with smokeless.

[Chill Wills]

Not according to Rowlands account. A machine rest held the rifle. All the shooter had to do was put his hand behind the buttplate and pull the trigger. Read Rowlands account as that is what he said about it............

45 2.1”
Well, I did say I could not remember well and so you did cause me to go back and read one account. There are other accounts. That will be for another day.
Check out the two * lines near the bottom.
Quoting some things from John Dutcher "Ballard, The Great American Single Shot".

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Rowland's Record Group
Boulder, Colorado.
May 16, 1901
Rowland's record group was 10 consecutive shots into .722 of an inch at 200 yards.

The rifle was a muzzle-loaded .32-40 Pope/Ballard.
The duplex load was 3 grains No. 1 DuPont smokeless, 7 1/2 U.M.C. primers, with the rest of the case filled with Fg Hazard's black powder.
Bullets were cast 1-10 alloy. Bullets were weighed to a tenth-grain and primers were also weighed.
*Rowland shot the rifle from a Stevens/Pope machine rest.
*Dutcher also believes the target was made in one day.

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All black has a place as does duplex and smokeless. I would hate to be without any of the three.