458 Win mag / 1st time re-loading advice

I purchased a 458 Win Mag Mauser/Whitworth with 100 pcs. NOS brass and lee dies. Due to limited supply on everything these days I have only been able to round up some Acme 458 405gr Boolits (measure 403gr) that are Hi-tech coated?. I was able to get a RCBS press Kit, and Hornaday trimmer. The only powder I could get is accurate 5744. I have yet to find primers but have a lead, hoping to get some large rifle primers from a friend.

I would like a reduced load maybe in the 1400fps range. a couple of example loads I have found for 405gr
Western 45-70 405gr std. press. 30.6gr 5744
Western 45-70 405gr hi press. 36gr 5744
Lyman 458 385gr 33gr 5744
Western 458 (gas check 405, bit hotter than i want) 45.9gr 5744

would starting at 33gr seem like a safe choice?

Thanks, I know there are lots of posts on reduced 458 but the supplies are so limited this is all I can get.

Also I understand with the coated boolits I do not need lube?

Thanks

Get a Lyman cast bullet manual, lots and lots of ways to make that elephant gun into a Trap Door Springfield.

No book data for this, but I've been using old AA8700 in mine. Real inefficient powder but accuracy is good and the smoke signature with lubed cast bullets is rather impressive.

The 458 Win Mag rifles I have owned all like IMR 3031 for full-power 500 gr loads. For reduced cast-bullet loads they all like H4895. Go to

https://shop.hodgdon.com/reloading-data-center

and choose your medicine. For cast bullet loads, load the 458 Win Mag data, click on H4895 on the check list to the right, click "Update Data," pick a bullet weight (350, 400, 450, 500), and reduce by up to 60% of the max load. In this range of data the velocity is very close to a linear relationship with charge weight.

Will get book coming, other powders are tough to come by these days. Anyone have any experience with 5477?

Thanks

I always wanted a barrel in that caliber to try black powder loads. Kinda like a rimless .45-70

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I got 2 cast boolits I shoot one for the 45/70 and the other for my 458 winny the 45/70 gets 400 gr lyman and the 458 gets a 385 gr coated lyman

The latest Lyman book the 4th edition only lists three bullets for 458 Win but no 405gr. Loads for closest weights on either side with 5744 are:

457124 385gr starting load 33.5gr 1431fps max 42.0gr 1706fps
457671 475gr starting load 34.5gr 1425fps max 40.5gr 1623fps

This in a Ruger No 1 24" 1-14" twist

The .458 Win Mag works very well as a belted .45-70 and .45-70 loads work just fine on the lower end. Obviously Full Tilt loads are going to be much hotter,,, but a Full Tilt .45-70 load is still well below a Full Tilt .458 Win Mag load, so you should be safe with any of them..

I shoot mainly RCBS .45-300 FNGC in my Marlin 1895. I started with 25 gr of 5744 and worked up until I got a usable 200 yard trajectory that I could stand to shoot 40-50 rounds of, in a morning. I peaked out at 35 gr of 5744 but then backed down to 33 gr as the recoil was more palatable there. My gun only weighs 8 lbs, yours is probably more like 10 lbs +? So it will soak up the recoil much better and you could shoot heavier boolits with less back side drama.

This load yields 1550-1600 fps for that boolit.

The 405 gr version of that boolit is .45-405 FNGC and the nose length is the same with more driving bands. Same with .45-500 FNGC which has more driving bands than the 405. These boolits were all designed to be ran in Leverguns where the OAL matters. Not as much with the Mauser. They will work just fine in your Mauser.

I'd say start at 30 gr of 5744 and work up until the recoil becomes unpleasant for you. Also this caliber responds well to Powder Coated Boolits which eliminate any possibility of Barrel Leading and open up the use of Plain Based Boolits.

I had a friend who loaned me his Ruger #1 that had been rebarreled in .458 Win Mag. The barrel was 28" long and a very heavy contour, and at 12 lbs the gun was a creampuff to shoot. And with my 33 gr load in the Win Mag cases it was super fun to shoot.

Randy.

Quote:

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Originally Posted by Tatume

The 458 Win Mag rifles I have owned all like IMR 3031 for full-power 500 gr loads. For reduced cast-bullet loads they all like H4895. Go to

https://shop.hodgdon.com/reloading-data-center

and choose your medicine. For cast bullet loads, load the 458 Win Mag data, click on H4895 on the check list to the right, click "Update Data," pick a bullet weight (350, 400, 450, 500), and reduce by up to 60% of the max load. In this range of data the velocity is very close to a linear relationship with charge weight.

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I have used this method in other rifles, that my math 60% of 77gr=46gr and 60%of 2349fps is 1400FPS trap door speed for a 405gr boolit

Take a look at Lymans 50th Manual it shows in your favor for AA5744

Thanks so much for reply, Really needed the confirmation and education.

Long ago I fired a friend's 98 Mauser in 458 Win Mag with a full charge load and 500 grain fmj bullet, (once). I got a bruise the size of a grapefruit on my shoulder from that, and the shot blew apart a pumpkin sized rock in a dry stream bed about 80 yards out, and turned it into aquarium gravel. I decided that there isn't a rhinoceros or elephant on this Earth that would taste good enough to hunt with that thing. (Besides, they wouldn't fit on my BBQ.):-D
If you keep cast loads "trapdoor" mild a 458 would be a dream to shoot. Just remember that when you step up a 458 to where it's no longer fun, you're only halfway to where it can go! My only experience with 5744 is with cast loads in 308, but I do reload for 45-70 in a 1874 Sharps replica. Once the shortage lets up I'd recommend that you try out Reloader #7. It would be a good match for the loads that you want.