Niche reloading of 45-90?... Duplex loads?.....

[Steve1]

Hi Folks:

I am a few weeks into this forum, and very pleased to see the local Montana input to questions etc. Lots of practical BTDT feedback!
Here's a quirky, but quite serious question... I have a C. Sharps Win 1885 in 45-90... 30" Bull barrel, Sole sights, 1:16 twist, It is a gorgeous rifle !!!!!

I'm about 18 months into loading 45-90, both the Holy Black, and that newer smokeless stuff..
I cast for this gun too, Hornady 410gr FP, ( kind of like the 405 Army load), and also a Hornady 535 Postelle...
I now have Lee 500 GC FP mold (maybe later for elk?)
I have shot BP, and smokeless loads.. and I'm not having too much success... 100yd groups vary 3-5"...
I'm still tinkering with loads, lube, COAL etc.. A recent range trip showed that my BP loads are super consistent, Goex 2FG at 70gr, 1190fps (for the 535) and SD of 3.8fps! Should be a perfect load... but.. why the 3-5"..? It may be me?....this was bean bagged... However the idea of a scope on a 1885 is sick!

Chrono of 45-90 -535 Goex FFG 70Grs.

With an old Winchester model 35, 22RF and irons I can hit a 1.5" target no sweat at 50 yards.. Yet the C. Sharps with Sole sights, 3X that!

I'm not a spring chicken, (68).. eyesight for irons is okay, but not perfect... but...

So, I'm curious as to what is a realistic load... maybe matching the older heavy bullet 45-90 loads... 500-535 etc. and BP velocities...
Smokeless gives Uber power, 1700fps and is a thumper... not what I need... ( for now)
I have a cool app for load development, Gordon's Reloading Tool... a genius, but sadly deceased...
So I sit here and dream up loads... suitable for mice to Buffalo.... it handles BP and Nitro powders too.
Also a British Interior Ballistics load dev tool, Google P-Max Black Powder Ballistics...
Great app, but I find their energy equiv for BP powders is about 10% lower than basic Goex... be careful!!

Looking for BTDT input and guidance, I have 10 Lbs of 2FFg.... but the primers cost too!

My thinking (guess?) is that maybe its fouling for BP loads... I could use a blow tube.. and all of that 1880s tech... Smokeless is too fast..
So does anyone have any actual experience of using that scary technology of Duplex loads for these calibers?
A 10% (in grains load of RL7) and the 90% load of 2FG... carefully compressed, and measured for COAL....
I know it's another rabbit hole, trust me a I have a few... but the C. Sharps should be a perfect target gun, but so far from mild 405/60Gr 2FG Goex to 535 and 90 Gr 2F its just not consistent.

I have cruised YT, and there are numerous folks who shoot duplex loads... less fouling, better consistency... 25+ shots without bore wiping....?

Where should I start?

Appreciate the feedback and suggestions.... I'd like to save months of try this and... sigh... adventures...

Best !

Steve 1 Florence MT .

 

[Handyman]

@Steve1 , it sounds like you are chasing tight groups with that Sharps. Your chrono shows the load is good, so the spread is likely from fouling, seating depth, or sight picture. Stick with the Goex and 535, clean every few shots while testing, keep COAL consistent, and try small tweaks with lube and bullet fit before jumping into duplex loads. Get one black powder recipe that groups, then build from there. I hope this helps.

 

[Steve1]

Hi Handyman, my apologies for the delay in response, I was in Yellowstone, no cell service...

Thanks for your thoughts on my 45-90 C Sharps 1885. I load for 270, 303, and a bunch of pistols, but BP and the big 45-90 bring new processes and workflows, and old issues not encountered in modern calibers. I think your suggestion of fouling is most likely the issue in hand, as my casting appears to be okay, 535 gr Postelles look good, and weigh very close to each other. My Chrono says I have a very low SD, also good.

I have some purchased 420 gr lead Flat point bullets that look much worse than mine! Some are dinged and have lube amount variability...
I use SPG lube, and have tinkered with various loads of FFG Goex... I have not yet cleaned between shots, so that my help reduce one variable.
I also have Alox, but not yet tried it... sticky brown weird stuff, yet some swear by it.

Your point about COAL and bullet seating vs lands is also I think very germane, and was an area I had planned to look into. I have a home workshop, lathe, mills etc... and have just finished making a bullet seating depth gauge... So, in my "copious spare time"... I'll remember the basics, one load, test COAL vs throat, and clean between shots. I have not seen any leading, and I have looked! Just the usual black crud and lube...

I'll work up some basic BP FFg loads, and experiment, but keep the variables to just one at a time.

Thanks!

Steve 1