? about these duplex loads

[blacksavage]

I see alot of talk about these duplex loads. But yet i dont get exactly what the proceduer to load these i would assume you guys are talking about a fast burning powder being loaded first with a slower powder on top?

[youp50]

Mix them if you like. I started with the booster separate and have settled in on mixing the two powders. One less thing in a possibles bag. Many others do load the booster powder first.

There seems to be two schools on duplex loads. The more learned use it to maintain a better burn to optimize bullet velocity. Then there are guys like me that use it to make sure the thing goes bang all the time, even at cold temperatures.

I use IMR SR4759 as a booster. The powder is used for reduced loads in CF cartridges. I am uncertain as to the speed of the powder. I know it needs less pressure to burn. It then creates the pressure needed to burn the main powder, in my application H4198.

Go to the old board and look up some of RB's pressure curve postings. It may help clarify things.

[blacksavage]

thank you between your response and a old topic i found pretty much cleared it up for me. I dont try anything unless i fully understand it and the principles behind. i have reloaded centerfire alot more than i shoot muzzleloaders and the initial thought of mixing powders sounded a bit scary big time no no in reloading cartidges

[shoot2reload]

I'd love to hear more about this topic! This question mirrors one of the first questions I asked on the old board, but I got a completely different response--I was told the idea was to layer the powders with the easy-ignition one closest to the primer. If I recall correctly, a friendly poster even showed targets with a tight-group doing the layering, and a scattered group with the same powders mixed.

Doesn't mixing minimize the booster effect?

[Richard]

Blacksavage................Duplexing is used to not only increase velocity but also in insure good ignition. I personally can't see why Youp50 would bother mixing the powders??? It really sort of defeats the purpose? Mixing the powders (provided you are using the proper amounts of booster and main charge) is not dangerous. As a matter of fact, I have found that mixing powders simply lowers the velocity. If I want a lower velocity, I use a different powder. In Australia where they do not have the variety of powders we have here in the states, they routinely mix and blend powders to arrive at a desired burning rate.
Sooooooooo, by mixing the powders you loose the effect of having a booster of fast powder to ignite the slower powder which enhances velocity. Tomorrow morning I will be down at our range along with Herman and our friend Bill where the temperatures should be 20*. I have twenty shots loaded with 15 gr. of V V N-110 which I will load first and then put 55 gr. of H-322 on top of it. This will push a 200 gr. .45 bullet to speeds approaching 2800 fps. I will be using 200 gr .40 cal SST's with Blue Harvesters and also sabotless with the 200 gr. Hor. FTX.
Richard

[youp50]

Richard,

I find it easier to carry one powder vial and and one sabot/bullet. Its the KISS theory, for me anyway. Yea, I think I do lose about 100 fps when mixed, but it has always gone bang at 20 degrees below zero F. The accuracy is not affected in my 50. No doubt I need to test some more...

You guys still shooting in a heated shack at the range? I am hoping that the Lake will ice over a bit and the temps will get down to the below 0 mark. I do want to test some more this winter. I may head to the range later today, still a balmy 13 degrees F out there... and the snow is butthole deep on a 6 foot Swede.

[edge]

IMO, mixing vs not mixing is similar to cleaning or not cleaning your breechplug....or opinions

It all comes down to your procedure. If you experiment enough you will probably find a load that will suit your shooting style.

Now if one person says that they lose 100 fps, and that is a consistent number then if they upped the charge or changed the ratio then they should be able to gain that 100 fps back. The total charge is a +- number that is not universal and neither is the ratio.

edge.

[boarhog]

Last night, I read Randy Wakeman's post in the "Pipe Bombs Thread". While his post was mainly about the relative merits of Toby Bridges, he also strongly cautioned against duplexing, whether layered or mixed. His position sounded, to me, similar to the "Legaleze" most manufacturers use to cover their backsides nowdays. I would be interested in hearing comments from some of you more experienced duplexers about this subject.

For me, duplexing makes a lot of sense. I am less interested in maximum velocity than many on this board. I really have no burning need to hit 3000 fps with 200 grain bullets, but RB and others have said that lesser loads of powders like H-4198 require a certain pressure level for good ignition. I think I would prefer to put 10 grains of a booster powder under a less than max load of 4198 if it will give me the same accuracy and dependability (but not necessarily the same speed) as the max single powder load. My recently bulged and replaced .50 barrel got it's best accuracy with a duplex of 10/55-n-110/H-4198 or Re-7. The bulge had nothing to do with the duplex. It was due to my failure to follow the basic safety rules I learned when I first got into muzzleloading. The double load I fired would have never happened if I had paid the least attention to the witness mark on my ramrod. Foolish!!

[Richard]

Edge........you are probably right on the "just add more powder" theory. But then you also add more recoil, right? Hey, as long as the load does what you want it to do, have at it!
Youp50..........Yup! It was "toasty and warm" when I got to the range this morning (14* out - 48* in). Herman and bill had two propane heaters going along with a 13,000 BTU "Kerosun"
Richard

[Jon]

Richard I envy you. I feel lucky to have a roof over my head. Keep up the great posts It is a lot of help for us less fortunate. Again glad your back.
Jon

[edge]

Jan 5, 2010 16:39:09 GMT -5 Richard said:

Edge........you are probably right on the "just add more powder" theory.

SNIP

Perhaps if you read my post completely you would see that I also suggested changing the ratio too!

snip

edge.

[Richard]

Gotcha SNIPPER ;D
Richard