460 S&W medium loads

[feets]

First, let me apologize if I dumped this in the wrong forum. Should that be the case, feel free to take a moment to kick the newbie and slide the post wherever it may need to go.

I'm wanting to load something around 300 gr lead at 1300 to 1500 fps in my braked 15" 460 S&W Encore. The idea is to find a fun load to slam rams at 200 meters in IHMSA. In my first attempt at silhouette I managed to do well with a 44 mag and 250 gr lead. My thought are that the longer and heavier .452 will keep their velocity and not drop too much more than the 429 mag.

One thing I've discovered is that nobody has any mid-range load data for the 460. It's either subsonic Trail Boss or big boy loads.
If I try the suggested 1800 fps loads I'll end up with velocities approaching 2000 fps and it'll be a bit stiffer than I'd care to shoot all day.

Hodgdon lists Varget and H4895 loads for similar weight lead in a 45-70 pistol. The pressures are about 1/3 the capacity of the 460. Is it safe to work up something like that?

Should I look at 454 Casull loads with a case filler? For those not familiar with it, the 460 has a larger case capacity than a 308 and works at a higher pressure.

Something that makes velocity easier is the fact that I don't have a cylinder gap. The factory Hornady 200 gr (gasp!) jacketed loads rated at 2200 fps in a revolver leave my barrel at 2700 fps.
The Trail Boss loads I've tried don't quite have the velocity I want. The 250 rnfp are leaving around 1200 fps with 12.5 gr TB. While that would be great for indirect fire, I'd like something a little flatter than the St Louis Arch.

Naturally, I'm not taking this barrel too seriously in the matches. Instead, it's something that I would have fun playing with.

I'd appreciate any info you'd have to offer.

Thanks,
Kevin

[Topper]

Hi Kevin,
H4895 & Varget will probably burn too slow for a 15' barrel.
M.D. Smith list the following loads for 460 S&W.
300 Grain Speer Uni-Cor SP (.451)
2400 28.0 gr. 1,392 FPS start
2400 30.0 gr. 1,550 FPS Max
Power Pistol 18.0 gr. 1,292 start
Power Pistol 20.0 gr. 1,359 Max
Note: I have not reloaded for this cartridge and I'm sure others can provide more loading advice than what I found using google.

[HammerMTB]

I am facing the same problem, but with a .500S&W. Since it is a high pressure, high performance cartridge, there is little data for lighter loads. I can't bring myself to shoot those poor paper targets with 2000FPS sizzler loads. Or maybe it's my old joints, from fingers to shoulder. Why beat me and gun?
So this is how far I have come:
I measured a .500S&W cartridge, like this: Put a spent primer in one, weighed it, then weighed it full of water. I found it held 59 gr of water.
Then I did a 45-70 cartridge. It held 73 gr water.
In neither occasion did I account for the volume of the boolit to be placed in the cartridge, just in case someone wonders.
The 45-70 was designed for 28,000
The 500 S&W design is for 60,000
Where I'm going with this is if you are reducing a known good charge in 45-70, I would say you are alright. This would apply to charges meant for original 45-70's, not those specifically set up for the Ruger #1 and similar high pressure actions.

So, a couple data points:
I tried 11 gr of Unique in a 45-70. It gave me 1111FPS avg behind a 340 gr boolit.
Curiously, I tried 2 of these with powder to front instead of back of case. Vel was significantly higher. Small qtys of powder in a big case can be weird. No sign of abnormal pressure, just inconsistent.
Another resource is the Lee Loading manual #2. In it, a method for interpolation of loads is given, specifically to find reduced loads.
I can only add that reducing a powder charge only works to an extent. Powders like to burn in a specific pressure range. Get below that and they get dirty.
One final caution: some slow powders should not be reduced beyond provided loading manual values. If I am trying to develop a reduced load, I simply don't use slow powders at all. If you want more info on that subject, look around the 'net for SPE or secondary pressure excursion.
Good luck in your quest. I have a friend with a .460 that wants to start handloading for it. It'd be interesting to see what you find.

[feets]

Interesting. I don't have any 45-70 to measure. The 460 S&W case I just checked measured 62.5 gr of water. Maybe I can do some math with the 45-70 pistol loads. I did find it odd that the rifle powders were only listed with the pistol loads, not the trap door, lever gun, or modern rifle charges.


Problems with partially filled cases is not new to me. I've had bad experience with Universal in 45 Colt. Not BOOM bad, just messy. When they were loaded with a standard charge I was able to tap unburned powder out of the cases and the barrel. It really needed a filler.

I've got some Pyrodex but stuffing that in a 460 would be messy too. I wonder if you could play the muzzle brake like a calliope? :)