I would like to find a source for hard cast, gas checked bullets between 425 grains and 475 grains in .458 Any ideas?

If you decide to cast your own,Lyman's cast mould #457671 might be what you're looking for.It's a gaschecked design weighing 475 gr.(weight will vary according to alloy of course)

Have you tried cast in your 458 yet? Try as I might, mine just will not shoot cast. Any jacketed will go sub MOA, but cast always go through the target sideways at 25 yards, when they even hit the paper. And yes, I tried every size, weight, hardness, alloy, speed, seating depth, base, ogive, you name it. The throat in my 77 is so long that there is no way to get the bullet anywhere near the lands and still have it work through the magazine, and single loading bullets with only about 1/16" of bullet in the case is not my idea of a fun afternoon. Anyway, you might want to try a few to see how your rifle likes them before making a major investment in a large quantity of cast bullets or bullet molds.

Big Bore...Thanks for the"heads up"on this.I've been thinking about trying cast bullets in the 458 myself.After reading your post,I'm re-thinking that.Is that the 458 win.mag. you tried it in?What twist rate?...Thanks

After looking at my records,years ago I played with cast bullets in the .458 win and 45-70 microgroove Marlin. After 1 year of Zero success ( i.e bullets hitting paper sideways or 6 inch groups at 50yrds), I learned how to make them play. First slug your barrel and determine its actual size. Not all .458's are .458. Then get a mold that will throw a Pure Linotype bullet .001 inches larger than the bore size. Don't size the bullets if you can avoid it,however, if you have to size them Lyman sizers work ok but don't wait too long as Lino gets real hard after 2 hrs. I've tried every alloy that I could produce and never found anything better than pure Linotype in the .458 Win or Modern 45-70. The load was 24 grs of 2400 with a tuft of dacron to fill the case to the mouth. Make sure you bell the mouth of the case first so you don't shave any lead on seating. Lube the bullet with SPG lube ( the blackpowder guys love this stuff) and seat the bullet to the crimp groove,making real sure the dacron is compressed.I didn't bother crimping in the .458 win, but heavy crimped the 45-70. A good crimp never seems to hurt anything and your chronograph will indicate if it helps or not. This load will shoot in just about everything I own to <1 inch groups at 50 yrds ( nice big ragged one hole groups) and about 1.5 inches at 100yrds. I've even won a couple of off-hand cowboy matches with it in the marlin 1895 45-70 which every gun hack claims can't be shot with cast bullets due to the microgroove rifling. The molds I used were a cheap Lee 405 grs and a Lyman 500 gr mold.
I even got this to work with a 300 gr lee mold and 28 grs of 2400.

Don't let my lack of success discourage you from giving lead a try in your 458. My 77 Ruger is indeed a 458 Win and it's twist is standard factory, 1 in 14 or 1 in 15 if memory is working today. My rifle is not the rule, because I have mostly heard positive things about the 458 and lead bullets, but to any rule, there are many exceptions and my rifle is a beauty of an example. I even sized my bullets to the throat +.001, .002, you name it, and every alloy you can imagine. The reason I mentioned it at all was just to put out a warning that before you invest a lot of money in a lot of lead bullets or expensive molds, make sure your rifle isn't like mine, and simply won't shoot lead. Get a box of a couple different weights, sized .001 over groove diameter-be sure to slug your bore-and check the diameter of your throat also. I am pretty sure that is where my problem is. The best advice I can give is get a box of 450 gr. hard cast heat treated gas checked bullets, sized .001 over groove diameter if your throat is not oversized. If your rifle is going to shoot lead, you should see some success with that bullet. If not, try .001 over throat diameter. If you can find pure Linotype, go that route next. By this time you should have some idea if your rifle is going to shoot lead. If all of your bullets are going through the target sideways at 25 yards like mine were at this point, look out. You may be in for a long haul.

Thanks for that excellent reply, that is why I come here! It seems no matter what idea somebody may have, somebody else here has done the homework already!

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