Home Forums Hunting & Shooting Express Rifles and Big Bores Only The great 458 Winchester. Everyone should own one at least once

Sir Russ,
King Four Five Eight wishes for me to tell you that you bring him tears of joy.

Thank you very very much beyond all words such as "buy a buy a donkey," "mercy boo koo boo koo," or "asante sana sana."
Long live the King of Cartridges !

The rifle used yesterday with Hodgdon Benchmark/ADI Benchmark,
24-1/4" barrel length, 1:10" twist Pac-Nor No. 5 sporter contour,
FN Mauser action (started as a Herter's .30-06),
Sunny Hill BM in a B&C stock with NECG 3-pos safety and Timney trigger,
it has yet to be Cerakoted:



The optics and scope mounts (Near Mfg rail and Burris low rings)
were no impediment to shooting.

By the order of fire:





One shot to verify newly installed scope is on paper,
then a scope adjustment and two more shots to finish fouling,
one more scope adjustment
then final 5 shots at smaller diamond:



Next five shots with 2 more grains of powder compressed into same COL, 3.380":



That was a surprising increase of velocity for only two grains of powder.
Next the COL was increased by 0.100" and two more grains of powder added
to the +4.166 grains H20 case capacity increase,
accuracy seemed to improve with less compression at 3.480" COL:



Final five shots with the 404-gr Shock Hammer at 3.580" COL and 84.0 grains Benchmark,
close to a full case load with no compression.
"Swift Reloading Manual Number Two" with 400-gr Swift bullet and about "one-caliber" seating depth
used 82.5 grains Benchmark for a 93% Load Density (LR/net fill) in Norma brass and 2511 fps MV.
That is supposed to be 62,500 psi or less.

The extra throat of .458 WinMag and lower friction of Hammer bullet with PDR bands
beats the .458 Lott by just over 100 fps with 1.5 grains more powder:

Last five shots of the day, after two shots to foul with brass bullets since the copper PDR bands left hardly any fouling.
Brass is slicker than copper, but the bearing surface of the CEB bands are much greater than the Hammer PDR bands.
A non-compressed charge of 78.0 grains Benchmark thus was able to get higher velocity with 400-gr CEB
than same charge did with mildly compressed load of 404-gr Shock Hammer:

There were no pressure signs with any of these loads, primers were flattened no more than before they were fired.
The Norma brass had very tight primer pockets to start with.
By the time the primer was seated, it was pretty well flattened and below flush with the case head's face.
There was no cratering of the primer indentations.
There was no brass extrusion onto the case head face, no ejector slot smears or bright marks.
No stickiness of bolt lift.
The cases ejected smoothly, effortlessly, falling out of the chamber.

The Woodleigh Bullets Loading Manual singled out Benchmark from the seven propellants they tried
in the .458 Winchester Magnum: "Benchmark gives excellent results in this cartridge."
That was in reference to Woodleigh bullets from 400-gr to 550-gr.
Benchmark offers many possibilities for loading more than just the 404-gr Shock Hammer and 400-gr CEB brass FN
at various COLs and performance levels.

Benchmark is the temperature stable powder very close to burn rate of IMR-3031.
IMR-3031 was the old standby for the .458 WinMag and 500-grainers at 2150 fps from a 24" barrel.
I was doing that in the last century, before the dark age of .458 WinMag denial descended upon the world.

IMR-3031 was an old favorite for use in reduced loads with fillers in the huge Nitro Express cases.
Same could be done with Benchmark, for low velocity loads in the .458 WinMag,
from .45-70 Gov't. to beyond .458 Lott.

Bless Jack Lott's heart.
He always meant for his wildcat to be done in an existing SAAMI .458 WinMag chamber with no setback of the barrel.
After he saw what Art Alphin and SAAMI did to the .458 Lott throat, he just could not bear it.

Ron, many thanks for this information! A few questions (definitely too many all at once):

First, where can I get some of those CEB 400 solids? What Lee factory crimp are you using? Are the Norma cases with their extra capacity necessary for use with Benchmark to get these velocities with these 400 grain bullets? Can you see any downside in using the softer Norma cases with high pressure loads? Finally, at this point in your research, do you consider Benchmark a better performer with 400 grain brass bullets than 2230?

Sir Ron,

Given the performance of the CEB BBW#13 450 grain 0.458” bullet @ 2400 fps MV, the 400 grain @ 2500 fps seems interesting.

Sir Bevan,
CEB makes a 400-grain Lever Solid that differs in having a shorter nose projection so it will fit in lever actions.
Otherwise it is constructed like the 450-gr and heavier solids.
This "Special" 400-gr brass FN was made with the bands moved baseward for a greater nose projection,
and also differs in having a greater interband Minor Diameter that is larger, 0.449", only 0.001" less than bore dimeter
so it is closer to riding the bore.
Michael McCourry designed it for use in his .458 B&M which has less nose room and shorter throat,
as well as helping me out by getting something better for loading in the .458 WinMag with 3 bands ahead of case mouth,
crimped right up against the bottom of the third band.
Trimming brass to 2.490" and seating even closer up against that third band, you can make it 3.340" COL instead of my 3.360".
Or seat it with only 2 bands ahead of case mouth and make the COL 3.250".

CEB would have to be asked to make another run of these, they are not a regular catalog item.
If I were doing it specifically for the .458 WinMag I would want an even greater nose projection.
Move the bands even more baseward, so as to crimp between the 2nd and 3rd bands and get a COL of 3.340".
Then I could still crimp behind the third band and get a LongCOL .458 WM+ load also, heh-heh-heh.

The Lee Factory Crimp Die for the .458 WinMag is a standard, regular production item. Used to be about $15.
In the Biden economy they are probably a lot more now.
Made for many standard calibers. If I see one that I don't have I buy it,
whether on dusty shelf or on internet sales catalog.

This batch of Norma .458 WM brass gives no indication of softness.
One fire-forming ought to make it hard.
I will anneal case mouths after third firing.

Benchmark seems to be as good as AA-2230/AA-2460 and supposed to be more temperature stable,
though AA-2230 /AA-2460 ain't bad in any way.
Try both and see what you like best.

Sir Khulu,
I bet your elephants would be just as dead with the 400-grain CEB FN at 2500 fps MV
as they were with 450-grain CEB at 2400 fps MV.
The great thing is that the .458 WinMag in your hands can do both.

Here is the no-problem Norma brass used with the Benchmark:



And,progressively zooming in:

Benchmark might be a little more bulky than AA-2230/AA-2460,
same weight filling a little more volume, but not much.
Norma brass is greater capacity, a little more than 4 grains water.
Take your pick of Hornady/W-W/R-P/Federal versus Norma.
It is all good.
The .458 WinMag can do it all with great ease.

Sir Ron,

Thanks again for all that helpful information. If you had to pick one available 400 grain solid right now (not including the 45-70 CEB), what would it be?

Sir Ron - Would you think any filler would be needed for a light Benchmark load?

Sir Thomas,
Yes do use a filler with any Benchmark load of less than 85% LR/net fill.
In the .458 I like the caulking backer foam rod of 1/2" diameter, sliced with a fillet knife on a cutting board.
It vanishes on firing,
no flurry of dacron snow,
no flaming toilet paper.
If you have any air space to fill slice off a disc of that foam at least twice as tall as the air space and poke it into the case mouth with a dowel. You won't go wrong with that.

Sir Bevan,
No good answer other than go heavier with
450-gr CEB.
A 400-gr CEB Brass (or copper!) FN
with band spacing best for .458 WM
versatility is still needed.
I will dig up some images related to
the quest for this other Holy Grail,
for discussion.

Compare the 0.460" nose projection (length ahead of case mouth to meplat flat) on the 400-gr Lever Gun Solid
to the 0.750" projection of the 450-gr Safari Solid:



Here is that one-off run of a 400-gr "Special Solid" by CEB and Michael McCourry:



Above are my measurements of single bullets with my verynear calipers.

This is why bands are like that on the 400-gr Special, to keep COL less than 3.0" on the .458 B&M:







"#13" is a generic term for "Bastardfile Bullet Works Nose Profile Number 13" or BBW#13,
regardless of length of nose projection.
When the nose projection becomes short enough to work in a Marlin M1895 .45-70, it becomes a "Lever Gun" solid instead of a "Safari Solid."

Since it isn't likely I need a heavy solid for anything I am likely to shoot here in the lower 48, how effective would the CEB 325 grain safari solid be when driven fast from a .458 Win?

https://cuttingedgebullets.com/458-325gr-safari-solid

Sir Bevan,
I think you know the answer to that.
Actually it performs about as well as the 400-grain "Special" Safari Solid.
Just to clarify it for my mind, I reviewed the McCourry Institute of Ballistic "Terminals."
There is a 325-gr Lever Gun Solid with 0.460" nose projection
and a 325-gr Safari Solid with 0.650" nose projection like on the latest 400-grainer.
Nose projection includes the first band in length of projection beyond the case mouth.
Short nose projection does not penetrate as well as longer, somewhere over 0.600" does better,
seems to be optimum according to MIB "Terminals" for the .458-caliber solids in the
high-order test medium tougher than critters by depth of penetration.

Marlin .45-70 velocity, about 2000 fps impact: ~ 37" penetration, 325-gr Lever Gun Solid



Whether 2200 fps or near 2500 fps impact: ~ 52" penetration, 325-gr Safari Solid





Higher velocity and same penetration has to go into some other form of energy dissipation/wound trauma/heat/noise ...

Unfortunately the lower velocity with the Lever Gun solid confuses the issue, but MIB research assures us that
longer nose projection (ahead of first CEB band) improves penetration.

Dead elephant shot in skull as a test of 325-gr Safari Solid:



Here is the comparison for 380-gr Lehigh Copper WFN, near 2200 fps impact: ~ 41" penetration



The wider, sharper edged meplat transmits trauma to tissues well if not aiding penetration.

Same lessons apply to 400-grainers:





After 450-grains of FN solid, little is gained by increasing weight,
a shorter bullet is inherently more stable:











The Bastardfile Bullet Works #13 (BBW#13) nose profile is the better nose profile with meplat of
about 67% of caliber (65% to 70% of .458" is 0.300" to 0.321" for about optimum),
and 13* hemi-angle on the truncated nose cone, 26* cone angle.