Big boolits and good starting loads

I bought some 520 gr. boolits from a Lyman mould 457125. The Sharps seem to like heavy boolits so I thought I would give these a try. There is no loading information I can find on these beasts. I have loaded them with both 5744 and 1 1/2 F powder. Has anyone had any experience with these? They are a .458 size lubed with SPG. I would like something around 1100FPS but I don't have a chronograph to check their speed. I was hoping to find someone that may have used these before and was curious what you have found to be a good place to start with these. The 500 gr. boolit loads seem to be O.K. but with these big boys I can't seem to get what I would like out of these guys. I am shooting a 30" Shiloh Sharps and a 32" Pedersoli Sharps. Any info about speed would be greatly appreciated.

Assuming the Shiloh is B serial numbered and the bullets are cast 20-1 or harder, somewhere between 68 and 70 grs of the 1 1/2 with a .030 fiber wad and the bullet seated with the driving band exposed, in fireformed cases with no crimp should give you around 1150-1200 fps. Assuming a good fouling control accuracy should be decent.
You'll likely find those bullets a touch small diameter for the Pedersoli, but the same load recipe as above , altho I'm sure you've probably already found out cases fired in the Pedersoli probably won't chamber in the Shiloh without resizing.

What alloy are the bullets? If they are too hard they probably won't work all that well. If they are between 25:1 and 16:1 they should work very well. Load themup like Don says. Don't worry too much about velocity. Better to go for accuracy and let the velocity be whatever it ends up being. You'll be somewhere between 1150 -> 1250 no matter what you do :-)

Fouling management is the key to a good load, whether blow tubing or wiping.

With respect to the 5744 I can't say.

Chris.

I load a 525 grain postell bullet over 23.0 gr AA5744. It chronos at around 1129 fps and is pretty pleasant to shoot. I shoot 40-50 rounds in the coarse of a match. Accuracy is pretty good as well.

I've gone as high as 26.0 grains of 5744 with 535 grain boolits in a 13 pound rolling block and recoil wasn't bad. Accuracy looks like it will be best somewhere near 23 grains.

I use 27grs of 5744 under a .515 gr bullet at about 1200FPS very accurate, with a mag primer. You may need to go with a larger diameter bullet, I needed to go to a .561, to get the accuracy in my rifle. Start lighter and work up to find your sweet spot ??

I am loading 27 grains of 5744 under a Lyman 457125 cast of 96/2/2, 525 grains from my mold. This runs right at 1300 from my Sharps and 1886 Browning. Tried lower charges and observed vertical stringing. Recently fired a 5 shot 3.5" group with this load at 300 yards from the 1886 with 4 of the five under 2". Recoil is pretty healthy from the 10 lb 1886.

I've loaded 53gr IMR 4198 & 520gr in my friends' Sharps 45-110. It's listed as a max load, but he wanted to see the diff from the 40gr IMR 4198 & 405gr pills.

agreeing with others on boolit size for the Pedersoli you proly find it does better sized at .460 (I have a Uberti 1876 with Pedersoli barrel - it dont like .458 boolits at all!)