.22-5-40 wrote on Mar 24^th, 2015 at 10:13pm:

You would be assuming some risks. I am not an expert  but fairly logical. If the rifle were mine, i would venture to guess that yes, i could use Unique, Red Dot, or Blue Dot, and could develop a safe and accurate 100 yard load at about 1,250 fps. The large case  would require more powder than the 45-70. Since i am using 14.5 grains Unique under 350 grain bullets  in the 45-70, i would start the large case at 13.5 grains and increase that load until i got to 1200-1250 fps or saw signs of trouble. I would use cast bullets, about 350 grain. 
Of course, this is all theoretical and risky. 

Cooking up your own loads is risky, true, but the risk can be lessened with a little study. I'll often start with Blue Dot loads for odd cast bullet cartridges, but there is far less data for blue Dot than there is for Unique. Careful study shows that Blue Dot can be substituted 1.4 to 1 for Unique for pressures that are close to the same, but you still want to be very conservative with starting loads. I like Blue Dot because it gives a softer push to start the cast bullet, but sometime Unique is the best choice. If I'm starting to load for an odd cartridge that I have no data for, I use a table of bullet base area to case volume that I put together and look for data for a known case with a little less volume to bullet base area ratio than the one I'm trying to develop. I can then scale data up or down as necessary, bearing in mind the weight of the bullet, which scales as well. More volume and less weight mean less pressure, which is the way to go when starting. Less volume and more bullet weight means more pressure, so that has to be taken into account if you start changing seating depth or bullets. Faster powder means more pressure, too. Older Lyman manuals have quite a bit of pistol powder data for various cartridges, and by scaling up or down as necessary, I can usually get to some sort of mild load that is a good starting point. I'm not interested in driving cast bullets as fast as I can, I just like getting really old guns shooting again. Now, here's the disclaimer - BE CAREFUL, BE CONSERVATIVE. If you don't feel confident about the load you are putting together, don't use it. I can't be responsible for anyone using this method. I can only say that it has worked for me to be able to shoot a bunch of odd-ball cartridges that most folks at the range haven't ever heard of and it's fun to do. Green Dot, Red Dot, Herco, PB, 700X, etc. are all powders I have tried and sometimes I find that there is a happy confluence of case, bullet and powder that works just fine in one gun, but is worthless in another. But if everything were easy, we'd all be bored.

.22-5-40 wrote on Mar 25^th, 2015 at 7:02pm:


To the best of my knowledge, fillers are not needed with disc shaped fast burning powder. .  In the past 2 years i have fired or witnessed firing from about 10 different rifles, more than 6,000 shots, 5 or 6 calibers, various cast bullets, all with Unique, Red Dot and Blue Dot. No prolems whatsoever.   
Blue Dot should work,  will take a larger charge, as mentioned above. 
I have a shooting buddy who uses Blue Dot in his 38-55, with amazing accuracy at 200 yards. Smaller case, granted...

Let me give you some direct information on Unique and the 45/70. This info is for BSed bullets so, the case volume is more like the 45/90 plus a little.

The bullet is a 409 gr PB spitzer and the test was for 10.0 gr Unique, primers and a filler.

Fed 150
Ave Vel, 971
ES, 19
SD, 6.9
Group, .84

Fed 150 w/filler
Ave Vel, 969
ES, 21
SD, 8.8
Group, 1.19

Fed 210
Ave Vel, 965
ES, 20
SD, 6
Group, 1.02

I believe the numbers speak for themselfs, a 42% increase in grouping w/o a filler.

These are 7 shot strings, two foulers to warm and condition the barrel and then, 5 shot groups.

It is a truly Unique powder

Frank

marlinguy wrote on Mar 24^th, 2015 at 11:01am:


Many years ago all my shooting buddies told me I was flirting with disaster for using Unique and Herco (45-70) and I caved in and stopped... still use Unique - but only in revolvers (.357 & .45 Colt )

I may have to start rethinking about using pistol powders because it actually seems to make a lot of sense.

Has anybody else ever tried using Herco instead of Unique?

John in PA wrote on Mar 26^th, 2015 at 1:00pm:


The filler I used was, the foam found in Downy Fabric sheets. A very open chambered, light foam. It was cut into 3/4" squares that weighed about 1/2 gr. Many CBA guys used it in the 90's, it didn't prove to have any accuracy advantage and quickly went out of favor.

I tested in 3 different calibers and while in some applications it worked as well as w/o a filler, it really wasn't worth the effort, w/o a advantage to be had.

My personal thoughts on fillers, is if you need to use them, your load isn't optimal and you need to use another powder or a different powder charge.

The only time that something even in the case mouth is justified, IMO is to keep the powder from spilling while loading the case when BSing.

As far as Dacron goes, Lyman doen't feel that it's safe to use (in any application) or with any other filler.

Frank

Unique in all my large cases....Especially 45-70 and 38-55. I tried it without something holding the powder against the primer and the SD was much higher than using a 3/4" X 3/4" piece of single ply toilet paper pushed down over the powder with a pencil.

Be aware the article calls out the type of powder kernels as being of utmost importance. Flat , wafer type kernels that can be "blown " around in the case by the primer before ignition seems to be the reason these powders work best in these large cases.

Number of years ago lot of the local Trapdoor shooters using 330-350 gr bullets for 200 yard offhand gong matches went to W231.  Tried it in my Trapdoor for a while never saw the advantage over Unique.

Guessing most of them used 231 because the guy that won a lot of matches used it.

Boats