Duplex Powder

[quigleysharps4570]

Was thinking of a duplex load for my 45-60...main charge will be Goex Cartridge Grade with the smokeless charge being one of which I have on hand. Here's what's on hand:
Alliant Unique
Accurate No. 9
Accurate 5744
IMR 3031
Hodgdon H335
IMR 4064
IMR 4350
My question is which powder do you all think would be the best for the duplex? Wanting to go 55 grs. of the Cartridge Grade and 5 grs. of the other. Any ideas would be much appreciated.

[hellgate]

Some of the older loading manuals (Lyman, maybe) have info on using duplex loads. Also you might want to check with the Cast Bullet Association for proven loads. It is easy to get into trouble with the duplex loads so I would recommend published loads from reliable sources. If my memory serves, I believe the shotgun powders were more typically used as the smokeless booster. I've never loaded them as I also believe they are not allowed in SASS shoots and quite a few of the BP target matches. They do, however reduce fouling.

[PJ Hardtack]

quigley

Of all the powders you list, 5744 would be the one I'd use - 4.2 grs of it wirh 55 BP. Other powders to consider are SR4759 and 4198, long used for duplexing BPCRs.

[Lumpy Grits]

No need to duplex with the correct load
More issues than it's worth.
LG

[quigleysharps4570]

Thanks for the input guys. Believe I'll give 5744 a whirl.
Hellgate I don't do the matches so that won't be an issue...my shooting is all done behind the house or at a friends place on the river, so anything goes.
You're right Lumpy...but I'm just wanting to play. 

[Junkman]

What do you intend to accomplish by loading the cartridges with a duplex load?

[Delmonico]

More important, has anyone read this? 

http://www.cascity.com/forumhall/index.php/topic,40688.0.html

[Lumpy Grits]

I shoot/load for BPCR, everyone that I know who started out thinking duplex was the way to go has stopped doing so. Due to issues ranging from cases swelling at the head due to the pressure spike of the smokeless powder, to bulged chambers at the chamber mouth for the same reason.
I will NOT duplex.......It buys you not one thing.
Respectfully,
LG

[PJ Hardtack]

Anyone who prefers not to shoot duplex loads in BPCRs is welcome to do so. Until such time as I feel I am endangering myself, my guns or anyone else, I shall continue to do so.

There is a history of shooting duplex loading ..... The following from "The Breech-Loading Single Shot Rifle" by Ned Roberts and Ken waters, noted riflemen and ballistic experimenters.

"Some riflemen discovered that loading about 8 grs of Dupont No.1 Rifle smokeless powder in the bottom of the shell as a priming charge, and filling the rest of the shell with black powder with a cardboard or blotting paper wad over it, resulted in as fine accuracy with a breech seated or muzzle loaded bullet, WITHOUT WIPING THE BORE AFTER EACH SHOT, as was obtained with black powder and wiping the bore.
This smokeless powder priming caused the rifle to shoot very clean indeed by preventing the black powder residue from fouling the bore, so that A HUNDRED SHOTS OR MORE COULD BE FIRED WITHOUT WIPING THE BORE and as fine accuracy secured with the last  shot as with the first.
In a very short time, therefore, practically ALL Schuetzen riflemen had adopted it as a priming charge, and many used this duplex loading until the manufacture of Dupont No.1 powder was discontinued in 1926.
This powder did not pit or corrode the barrel when used alone because the residue left in the bore was pure carbon,; also SINCE THE BURNING TEMPERATURE WAS ABOUT THE SAME AS THAT OF BLACK POWDER, IT DID NOT ERODE THE BULLET SEAT OR BORE."

The book goes on to report that the Dupont powder that replaced No. 1 (Schuetzen Smokeless) was even more useful and successful used alone or as a priming powder in duplex loads. Steve Garbe has also written on the topic in his BPCN magazine.

So, unless someone can come up with with something to refute this, I regard the opposition to duplex loads as another of those "... everyone knows ..." gun myths based on ...... ? Strange how those that actually use duplex loads like them while the 'experts' that don't pan them.

When I first began duplexing, I was advised to prevent mixing of the smokeless and BP by compression, negating the use of a separation wad of any kind. I do this, compressing as I would for a 100 % BP load.

[Junkman]

PJ,

I was not refuting your duplex loading. I wanted to know what the purpose was and you provided me with the answer. Now I know. Good luck with your experiments and please inform us how it goes. 

[Lumpy Grits]

Duplexing is the answer to a question yet to be asked 
When the smokeless goes off, which is must faster burn than any BP, you are trying to push everydangthing else in that case before the much slower burning BP lights off. That is why you see a bulge in the case head after a few loadings that is a PITA to size down.
Your correct in it's your gun and do as you please.
I for one mhave to much time and $$$ into my Shiloh's to do something this "off" and unneeded.
Respectfully,
LG

[PJ Hardtack]

Hi 'Lumpy Grits' - I believe that we know each other from the Shiloh forum. That or some impostor has appropriated your alias .... ;>)

I've heard the same argument re: using mag primers in BPCR reloading. I had some mag primers that I started to use up in my 50-70 loads and found no advantage I was aware of. The argument was that the hotter ignition would do what you described - push the compressed charge ahead causing problems; especially in heavily compressed loads with long powder columns.
If it did, you couldn't prove it by me, but I've only used mag primers in 50-70 with no issues. Garbe's experimentation led him to believe that a 'cooler' primer was actually better for igniting BP. It isn't that hard to ignite. What matters is consistency.

I'm not experiencing the case head bulging that you mention. Makes me wonder what you were doing, or are you just passing on anecdotal information? As for any aspect of duplexing being a PITA, when you are acquiring lead, casting/sizing/lubing, sizing/depriming/annealing/cleaning/trimming brass, weighing/measuring/drop tubing/compressing powder charges ..... what's one more step in the process? It's already labour intensive.

You aren't the only one with time and money invested in your Shilohs. I'm down to five, having sold off one of my '63s to guy who just couldn't wait to order one. I've had two Farmingdale locks upgraded by Kirk Bryan, new gas plates fitted on two '63s and returned my new 50-70 carbine to have the stock shortened. They are most expensive rifles I own, what with all the shipping and importation costs and hassles!

As for duplexing being "off", give me chapter and verse to support your claim - like I did. As for it being "unneeded", that's your opinion. The reason it's banned in BPCR silhouette matches is that there is no way to regulate or prove the loads. Regrettably, people cannot be relied upon to be honest, ethical or safe, hence the prohibition of duplexing.

I suggest that if it was safe and accurate enough for turn-of-the-century riflemen, it is still so today.

[Lumpy Grits]

YUP. that "B" me on Shiloh..
I have had my best loads with LR match primers(Fed or CCI)
Since you say you are a member of the Shiloh forum why don't you ask there?
Also, use "search" on that site for more information to your ans.
What I related to you was "first-hand" with "eyes-on" helping other BPCR folks at the range. None of them duplex now, BTW.
I will never duplex with what I have seen. No need/want to.
Cheers,
LG

[PJ Hardtack]

LG

I know better than to ask ANY question on the Shiloh forum. Too many 'experts' for my liking. I mentioned finding an unfired Browning .50 ML 'Mountain Rifle' on the Shiloh site recently and was buried in negative remarks from guys who have never owned one or shot one!
On the Canadian 'GunNutz' site, I got nothing but congratulations from guys that own and shoot one; regrets expressed from those that did and sold them.

One thing I like about this forum is that few members feel the need to feed their egos by listing the rifles they own, the options on them, etc. If anyone is that interested, they can check the Shiloh site or catalog to see what's available.

On the Shiloh forum, I mentioned that I occasionally roll a sized/lubed Lyman 515141 with a .54 calibre 60 gr Pyro pellet for a quick, easy handling paper cartridge for my '63s. Again, I got buried in negative remarks from guys that don't even own or shoot a '63! These same guys shoot '74 cartridge guns with bullet weights and twists that didn't exist historically. Go figure .....

[Lumpy Grits]

I give you a source for info. that YOU asked about. 
Then, you decide that you won't use the source with some BS reason 
Guess you really don't want the truth then......
LG

[PJ Hardtack]

Whoa there, Cowboy!

For a start I didn't ask for any information from you or anyone else, I was offering it to the original poster, quigleysharps4570, who made an inquiry about what smokeless powder to use of what he had on hand for duplexing.

I did challenge you to give me 'chapter and verse' to support your claims re: the down side of duplex loading. That means quoting sources and references. I did, to support mine, (and I could give you others) and have had results based on successful empirical experiment and observation. Your opinion is based on ..... ?

If there is any BS flying around, it's coming from your end of the corral, not mine ..... ;>)

[Beauregard Hooligan]

Easy gentlemen. We can disagree without being disagreeable.

To the OP's question: I don't like the use of duplex loads, mixing smokeless and BP is just a bad idea. I'd either load with BP, or go smokeless. Of the powders listed, I use Accurate 5744 in my .45-70 Remington Rolling Block. I keep my loads mild as the RRB is, like the Sharps, a fairly weak rifle; the books say stay under 18,000 PSI, so I do. I shoot 26 gn of Accurate 5744 under a 405 cast RNFP bullet with SPG lube, or 25 gn under a 500 gn round nose, also lubed with SPG. Those loads are safe even for a Trapdoor Springfield. I poked a hole in a mule deer with the 405 gn bullet a few years back out of my scoped Marlin 1895 lever gun, and it did a nice job of putting that buck down. Here's a couple of photos of my Rolling Block:







Now, Can we please get back to a respectful exchange? 

[quigleysharps4570]

Nice little Rolling Block BH. 

[PJ Hardtack]

Beauregard

Go back and re-read the postings ..... who was being disrespectful to whom? I don't hide behind a keyboard saying things that I wouldn't say to a man's face. I also back up what I say with facts, references and experience; not hear-say and 'common knowledge' which is often bogus folklore.

Can you give me a reference for "mixing smokeless and BP is just a bad idea"? I thought that I made it plain that the old riflemen used wads to prevent them from mixing and I achieve the same through compression.

You are also forgetting that even Shiloh advises not to use smokeless powder in their rifles unless it is chambered in a cartridge like 30-40 Krag. You and others have found out that the 40% rule (smokeless to BP equivalent) works rather well with some powders (4198, 5744) and is safe in sound rifles, even Trapdoors. I shoot duplex loads, 100% BP and 100% smokeless loads in my Trapdoors just fine.

Some of us have had similar success and experience with duplexing. I'm still waiting for some firsthand knowledge and reports of problems with duplexing.

[Beauregard Hooligan]

Beauregard

Go back and re-read the postings ..... who was being disrespectful to whom? I don't hide behind a keyboard saying things that I wouldn't say to a man's face. I also back up what I say with facts, references and experience; not hear-say and 'common knowledge' which is often bogus folklore.

Can you give me a reference for "mixing smokeless and BP is just a bad idea"? I thought that I made it plain that the old riflemen used wads to prevent them from mixing and I achieve the same through compression.

You are also forgetting that even Shiloh advises not to use smokeless powder in their rifles unless it is chambered in a cartridge like 30-40 Krag. You and others have found out that the 40% rule (smokeless to BP equivalent) works rather well with some powders (4198, 5744) and is safe in sound rifles, even Trapdoors. I shoot duplex loads, 100% BP and 100% smokeless loads in my Trapdoors just fine.

Some of us have had similar success and experience with duplexing. I'm still waiting for some firsthand knowledge and reports of problems with duplexing.

I don't care who said what, it was the tone that could have been more polite. I try and be at least polite and civil no matter the provocation, and that's been working well for quite a while. There is certainly nothing lost by avoiding discord. 

My comments about duplex loads are based on my personal opinion that it complicates loading and safety. Call it a gut reaction, but I would avoid using duplex loads unless there was powerful evidence that it significantly improves performance without sacrificing safety. I'd be interested in learning more about it, in a friendly and companionable way.