Discussion in 'Reloading' started by Quaticman, Nov 7, 2019.
What is your "go to" powder for the .458 Winchester Magnum with 500 grain bullets?
I heard that some factory ammunition gets good velocity by either blending powders to a secret recipe, or using some kind of secret powder. Any thoughts on this?
I’m not too worried, I’ll cheerfully use 2206H and am happy with the results.
IIRC, ADI AR 2206H is equivalent to 4895 and AA 2460
I've tried them all...nothing impressive-always in the 2,000-2,150ish fps range (even w/ longer 450 gr Barnes bullets.) Traded in favor of the PERFECT .416 Chatfield-Taylor.
450 Barnes Ramshot TAC
500 Federal Ramshot TAC
I do recall the great Woodleigh bullets being the shortest, so try those with the max, compressed powder loads and you'll prob have slightly better success. Kevin Robertson is dead-on about this short mag's limitations. Use the 450 gr bullets to get the velocity up to the effective minimums. My son shot a buff with one once (after we got to within 20 yards!) Ok as a stopping round, only because those sorts of distances are ok with it. (TAC is made by the same co. as Western, AA-all very similar, denser, more compressible grain-sized powders).
Not surprisingly, the gun was very accurate and a pleasure to shoot relative to most big bore carridges!!!
From powders that are easily available to me, I'd try Vihtavuori N133 or N530 first.
I use H335 and Accurate 2230 in my Zastava .458 WM. At near Max loads I get an average, 5 shots, 2140 fps shooting Hornady 500 grain DGS and DGX bullets.
H335 and RL7
A few books, including Hornady (possibly Nosler as well?), indicated H335 as ideal, so that's all I've ever used. Starting load in Hornady is 67.5, maxing at 76.3.
Does anyone have any good data for a 500gr Gas Checked cast bullet load for the 458WM or 458Lott??
I also have a Zastava M 70 and will be using the same Hornady bullets.
Using the Accurate Mold 46-500L2 I have tried the following:
65.0 gr IMR 3031 for 2038 fps
69.0 gr IMR 3031 for 2150 fps
65.0 gr IMR 4064 for 1940 fps
74.0 gr H4895 for 2218 fps
72.0 gr Ramshot X-terminator (Belgium production) for 2116 fps
74.0 gr Norma 202 for 2093 fps
74.0 gr RL-15 for 2044 fps
76.0 gr. RL-15 for 2096 fps
64.0 gr RL-7 for 2010 fps
all velocities taken @ 15 feet from chrony out of 24" barrel
Check out the Accurate Mold website for dimensional drawing of the bullet. It has two crimp grooves and a full diameter nose to help fill the 458WM throat. IMR 3031 really shines on 1900-2000 fps practice type loads. I use data for the old Hornady 500gr RN soft point as a reference when working on loads.
Please throw some loads out there using W748 with Speer 350 and Barnes 450 and 500 grainers! This is what I have on hand, so would appreciate it! Thanks!
H335 is the best (on paper) with Barnes TSX. Achieves good velocity with less than 100% LD.
In fact, I just loaded some 458 WM today with the 450gr TSX over 70.5 gr of H335.
Not a max load, but for practice it still should reach 2150 or so. Max loads go to 2275 or so.
Thanks Toby! Everything I’ve read states H335 is one of the best for reloading the .458 WM. I just wanted to use up the nine pounds or so of 748 I have, then switch to H335. I’m just looking for some light to moderate loads with the 748 and the Barnes bullets I have. My Hornady manual shows 74.0-79.6gr with their DGS or DGX 500 gr bullets, but since the Barnes is longer, I’m just not sure? And it doesn’t show a 450gr bullet only their 480gr? Bruce Moulds was kind enough to send me some loads using W748, but they weren’t specific using the longer Barnes bullets. Maybe it doesn’t matter if the bullet weights are the same?
In my rifle I have had the best results with AA2230 and Alliant RL-10x.
With 500 gr Woodleigh and Hornady bullets my records show 75.0 gr of AA2230 being a safe but max load at 75*F and gave a 5 shot average of 2240 fps. 72.0 gr yielded 2140 fps and 73.0 gr gave 2175 fps. I settled on the 72.0 gr as the preferred load and 3.280 OAL.
Looking back through my binder, with the RL-10x and CEB 450 brass solids my load is 69.0 gr and yields an average of 2284 fps and very moderate pressure at 70*F. 69.0 gr of 10x is not a compressed load with the 450 gr CEB. OAL is 3.250.
None of these loads are above published maximums.
A note of CAUTION!
I have found RL-10x to be less affected by temperature than AA2230 and some of the other commonly used ball powders such as H335 and WW748. When using a compressed load of ball powder I would strongly recommend careful testing at increased ambient air temperature. Additionally, if you let a cartridge bake in the chamber with the rifle setting in the sun on a 90 degree day with a compressed load of virtually any ball powder I have tested you will very likely end up with a sticky or stuck bolt. Trust me. I have experimented with this. If you plan on hunting Africa in hot temps, I would make certain your load is well below max. Or even better, avoid compressed loads of ball powder. There is a long history of people experiencing this issue. In fact, in spite of my strong urging a friend of mine experienced “problems” in Africa last year using a max load of ball powder (heavily compressed). He even “tested” the load at 90*F here at home without a problem. But he didn’t try letting the rifle sit in the sun for a while with a round in the chamber and then fire the round. For whatever reason, compressed loads of ball powder react more violently to this test than non-compressed loads of extruded powder. At least that has been my experience.
I hope this is helpful info. As ALWAYS, only YOU are responsible for your own choices when reloading. Make smart ones
^^ Excellent post IdaRam. It would pay to heed that advice and warning, but alas some or maybe most won't.
I have never figured out why 50-100 fps more vel in a (fill in the blank caliber and especially a DG intended caliber like the 458 WM) is more important than a 100% reliable load for a very expensive trip where the COST of that little extra vel may be an aweshiite or failure precisely at the time it is most critical not to have such a problem!
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