Yeah, not too much reduced load data for the 460 but some for the 454 Casull which you can base some loads on.
Concerning using the 45LC & 454C cases in the 460, I only shoot mine at the indoor range (25yds max.) so that's not much for the "free ranging" shooters but my "off the cuff" check using a 250gr XTP bullet in these shorter cases gave similar results & satisfactory for this distance. But using lead bullets is another story. Mine (3-1/2" Carry) doesn't care for lead even in the 460 case, but in the much shorter cases they were noticably worse, so I don't load plain cast lead anymore. However, I have loaded up some 460s with Missouri Bullet's 250gr Hi-Tek coated casts, at reduced power, but I haven't got to the range to try them yet though I believe they'll be fine from my other loadings with it.
I like to have a mix of power loads too. You didn't say what powder you have available to use for reduced loads?
My favorite 460 reduced load combo uses Unique & 230gr Zero JHPs. I've used from 13.0gr to 16.0grs (~1030-1275fps) with this. These are still pretty snappy (~37-45K CUP ?) but I've never tried going lower. 14.0grs is my usual load.
I seat the bullet just past the ogive/midline & then use a taper crimp. Since the crimp is just at the curve (~.449" dia.) & these are reduced loads, jump crimp is not an issue. The Zero bullets are inexpensive & tough enough for this load & accuracy is satisfactory for this distance for me. These loads fill the case from 59% to 67% full but, as always, be mindful of dispensing errors.
I'm almost out of Zero bullets so I bought some Xtreme's 230gr heavy plated concave base bullets (rated to 1500fps) that I've also loaded up to try next trip to the range. (I did a smash test on these & the plating is bonded very well to the lead.) The Xtreme bullets are .452" & I think they'll be good for this reduced load, but I'll let you know.
I've also tried some Bluedot, for mid-power loads, but otherwise it's mainly full charges of I4227, 2400 or W296 with Hornady XTPs too.
I'm sure someone will poo-poo these but if you're a conscientious loader, you shouldn't have any issues.
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Xtreme 45-41-357 bullets - smash test
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