The ACCURATE SMOKELESS POWDER LOADING GUIDE Number One of 1994 was written by the folks in McEwen, Tennessee (ACCURATE ARMS COMPANY, INC.) before the line was sold to Western Powders of Montana.
The original line included a "BR" designation on two of the powders:
AA-2015BR and AA-2495BR
They are both single-based, extruded propellants developed for "bench rest cartridges."
2015 is smaller grained and faster burning than 2495.
Comments from AA-Co., Inc.:

"2015BR- A single base, small-grained, extruded propellant developed specifically for "bench rest cartridges," such as the PPC and BR series. This powder was tested at the Bench Rest Nationals in 1990 and subsequently adopted by shooters such as Ferris Pindell and Sal Ventimiglia. 2015BR is extremely flexible, giving excellent performance in many cartridges from .22 Hornet to .458 Winchester Magnum."

"2495BR- Very similar to 4895, this single base, extruded propellant gives satisfactory performance in a wide variety of cartridges. It offers service rifle shooters who prefer extruded propellants an Accurate alternative to our 2520. This is absolutely our best propellant for shooting cast bullets in the .45-70 Govt."

Well ! I am extremely happy with AA-2495 for shooting cast bullets in the .458 WinM!
It has a no-filler-needed bulkiness and speed that is just right for 75%-Rule-DBR efforts,
and it is amazingly more often a 100% burn-completion powder
with a wide range of pressures and bullet weights.

Proposed 75%-Rule-DBR testing in .458 WinM! 25" barrel:

600-gr Barnes Original, 3.580" COL
62.0 gr AA-2495 (95% LR)(100% Burn) >>> ~1800 fps @ < 50K psi
vs.
450-gr TSX, 3.580" COL
62.0 gr AA-2495 (93% LR)(100% Burn) >>> ~2000 fps @ < 35K psi
450-gr TSX, 3.340" COL
62.0 gr AA-2495 (107% LR)(100% Burn) >>> ~2100 fps @ < 45K psi

Above is based on what I think QuickLOAD is useful for, making allowances for the over-estimations of velocity and pressure that it yields,
since it is bumfuzzled by lack of throat handling.

The 75%-Rule-DBR gets even more exciting when you consider the 400-gr & 300-gr combos.

The ultimate would be a 450-gr FN Brass Solid & 338-gr Ballistic Tip combo, yet to be created.

.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

quote:

Originally posted by .458 Only:
It would help immensely if people would read the whole thread rather than "jumping in" here and there, and out of context making false assumptions about RIP's work!

In preaching/teaching for over 63 years I usually do so in a progressive theme or "series". I also do that in blog writing. Most who follow them understand that not everything I say, know or believe is stated in any single one of them -- so it is with this thread.

It's like some people taking a single verse out of Scripture and building a false theological assumption from it -- a text without a context is a pretext for a contrary argument! (See Jesus in a contest with Satan who uses Scripture as a means to tempt him: Gospel of Matthew chapter 4, verses 1 - 10) Such being a dishonest use of the Bible -- of which every part has a context.

Bob
www.bigbores.ca

Absolutely !!
Buy a donkey

Howdy All. .
Been busy building our house trying to get the roof on before snow flies.
Rotator cuff surgery has been successful Thank God. I'm4 months post op. I'm being careful. But have to Frame On ! At 60 its not as easy as it was at 40 that's for sure.
I did get a bull caribou on my way thru Unit 13 B evening before last.
Sadly I did not use The Spruce King as it still needs optic and stock work.
I did use one of the 458s offspring. I blooded my Kimber Montana 338 Win mag.
There was no great hunting involved on my part tho. I pulled into a shoe fly turn out along the Richardson Hwy to scrub bug guts off the windshield. And there stands this nice meat bull. Just standing there eating. It was The Lord that kept him standing there just off the driveable surface of the road while I parked, got out and walked around the truck opened the passenger door and unzipped the soft case. Got the rifle out, opened the action and loaded the rifle with 3 shells from my front pocket,chambered a round walked off the driveable surface of the road and eventually got a shot off. My left arm isn't fully up to snuff when it comes to holding / aiming off hand. The first shot, ment for between the lookers was a bit off . it rocked his world but he walked across the roadway and down into the ditch part way. I crossed the road. Got down in the ditch. Decided not to play it fancy. He was starting facing me. I held for the neck/shoulder jct and dumped him.
250 gr Remington Core Lokt . range 30 yards or so.
Praise God! Meat on the ground!

Weeeeeellllll doggies !
Another Prodigal Missionary has returned.
Buy a donkey, CTF !
One shot meat, two shot maybe ... done !
Done with a shoulder still on the mend.
And the new Cabela's Lodge of The Interior is coming along.
Congratulations.
See the Anchorage, Alaska store for architectural pointers on that green roof:



.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

I have read this entire thread... I fully understand the mission. The mission argument is valid. My point has always been that in a thread full of ballistics data gathered from custom-built 458 Win rifles, why would anyone constrain themselves to SAAMI specifications for the chamber!?!

I did not just come into the middle of your “scripture” and pick a few variables. But the mission is very much based on picking arbitrary variables (SAAMI spec throats) and making great ballistic claims about how a cartridge with less case volume produces more power than a larger cartridge. I get that the 458 Win has more internal volume than the Lott if you seat the bullet farther out. I don’t think it’s smart to seat a bullet so far out of its case that you can pop the bullet out with your fingers, especially in a dangerous game rifle!

In this case, I cannot think of a more apt comparison than to an argument over interpretations of scripture. That is exactly why this thread is so long. A point is made, then someone changes a variable based on their beliefs.

I will add that it would benefit this work greatly to obtain a pressure barrel and run some pressures on some of the top-end loads presented here. It would be a real tragedy for someone to lose an eye, or worse, trying to make a 2.5” magnum case produce over 6,000 ft/lbs of energy.

Respectfully,

—-Catter

PS- RIP, I guess at some point I will have to admit you are correct in your mission. You DID join Accurate Reloading a few days before me 19 YEARS AGO! Can you believe it has been that long???

How is the longer win mag throat going to work with-or seat out jacketed bullets? Like Wildcatter says, how is the short case going to stand up to max pressures using powders other than AA2230?

quote:

Originally posted by Ready Aim Shoot:


How is the longer win mag throat going to work with-or seat out jacketed bullets? Like Wildcatter says, how is the short case going to stand up to max pressures using powders other than AA2230?

But it is based on a 3.6" OAL for both the Winchester and Lott. End of story.

quote:

Originally posted by Wildcatter:
I have read this entire thread... I fully understand the mission. The mission argument is valid. My point has always been that in a thread full of ballistics data gathered from custom-built 458 Win rifles, why would anyone constrain themselves to SAAMI specifications for the chamber!?!

I did not just come into the middle of your “scripture” and pick a few variables. But the mission is very much based on picking arbitrary variables (SAAMI spec throats) and making great ballistic claims about how a cartridge with less case volume produces more power than a larger cartridge. I get that the 458 Win has more internal volume than the Lott if you seat the bullet farther out. I don’t think it’s smart to seat a bullet so far out of its case that you can pop the bullet out with your fingers, especially in a dangerous game rifle!

In this case, I cannot think of a more apt comparison than to an argument over interpretations of scripture. That is exactly why this thread is so long. A point is made, then someone changes a variable based on their beliefs.

I will add that it would benefit this work greatly to obtain a pressure barrel and run some pressures on some of the top-end loads presented here. It would be a real tragedy for someone to lose an eye, or worse, trying to make a 2.5” magnum case produce over 6,000 ft/lbs of energy.

Respectfully,

—-Catter

PS- RIP, I guess at some point I will have to admit you are correct in your mission. You DID join Accurate Reloading a few days before me 19 YEARS AGO! Can you believe it has been that long???

All 458WM rifles used in this thread use SAMMI chambers, throats, and 3.6 magazines, so I do not see anything about that being arbitrary. Arbitrary would be if the 458 WM prophets would have modified away from the SAMMI standards. There are some plus p loads as indicated, but the Lott mark of 500 grains and 2300 fps has been met with the 458 WM with standardized pressure, standardized magazine, and standard chamber with standard throat. More conservative there is no reason the 458WM cannot obtain 500 grain at 2150 fps.

I was a 458 Lott heretic. I still like longer cases for ascetic reasons. I am convinced. I do not understand why Art Apline did what he did to the Lott even after reading his explanation.

I see the Lott for guys who do not handload, like me, and the 458 WM for guys, like Ripp, who can make it sing.

The WM has won the long war. The 458 WM is chambered is still chambered in an excellent factory rifle being the Model 70 African Express. The 458 Lott has lost the Ruger RSM and CZ 550. That leaves on the 458 WM if buying a new rifle.

Is the Caprivi in 458 Lott still offered?

quote:

Originally posted by Wildcatter:
I have read this entire thread... I fully understand the mission. The mission argument is valid. My point has always been that in a thread full of ballistics data gathered from custom-built 458 Win rifles, why would anyone constrain themselves to SAAMI specifications for the chamber!?!

I did not just come into the middle of your “scripture” and pick a few variables. But the mission is very much based on picking arbitrary variables (SAAMI spec throats) and making great ballistic claims about how a cartridge with less case volume produces more power than a larger cartridge. I get that the 458 Win has more internal volume than the Lott if you seat the bullet farther out. I don’t think it’s smart to seat a bullet so far out of its case that you can pop the bullet out with your fingers, especially in a dangerous game rifle!

In this case, I cannot think of a more apt comparison than to an argument over interpretations of scripture. That is exactly why this thread is so long. A point is made, then someone changes a variable based on their beliefs.

I will add that it would benefit this work greatly to obtain a pressure barrel and run some pressures on some of the top-end loads presented here. It would be a real tragedy for someone to lose an eye, or worse, trying to make a 2.5” magnum case produce over 6,000 ft/lbs of energy.

Respectfully,

—-Catter

PS- RIP, I guess at some point I will have to admit you are correct in your mission. You DID join Accurate Reloading a few days before me 19 YEARS AGO! Can you believe it has been that long???

Wildcatter;

It's obvious that you still don't "get it", or you don't want to as it spoils your assumptions!

I've been loading bullets LONG in any action that permits it since I started handloading 41 years ago. I could list all the cartridges here but they start with the .22 Hornet and go all the way to my favorite of all, the .458 Win Mag. So, all I've done with the .458 Win Mag is what I've done with all the others where practical sense makes good sense! Getting bullets closer to the lands makes good practical sense for accuracy purposes as well as leaving more room in the cartridge case for the right propellant. In addition, re the .458 Win Mag, even when loaded to maximum practical COL there is still more "free bore", or whatever it may be called, than the Lott when constrained to a COL of 3.6".

Never has there been an issue of pulling the bullets loose with the fingers! Just not possible when crimped into a cannelure either "home made" or one provided by Barnes in their TSX's or GS Custom. In the situation of a single-shot, as the Ruger No.1, they don't need a crimp as long as start pressure of each is the same.

As to actual psi, if the COL of the .458 Win cartridge is the same as the Lott, and the same amount of the same propellant is used under the same bullet, fired in the same length barrel, the psi of the .458 Win should be slightly less due to the longer throat (yes, even with the bullet seated "long"). And therefore, more powder could be used to bring psi equal to the Lott that should give better MV.

All of it has been hammered here by RIP, and if I may add -- by moi meme!

So your contrary arguments are without basis!

Bob
www.bigbores.ca

quote:

trying to make a 2.5” magnum case produce over 6,000 ft/lbs of energy.

There is a way to do this, 6000ft# in a 2.5"case:

1. Use a .589" Rigby casehead.
2. Go up to 50 caliber.

The 500AccRel (and its sisters) is an amazing cartridge. It will do 7000ft#

I wonder how a 458 sabot to 300 would do in a 458 Win Mag?

quote:

Originally posted by boom stick:
I wonder how a 458 sabot to 300 would do in a 458 Win Mag?

What twist rate on the barrel ?

quote:

Originally posted by LHeym500:
... The WM has won the long war. The 458 WM is chambered is still chambered in an excellent factory rifle being the Model 70 African Express. The 458 Lott has lost the Ruger RSM and CZ 550. That leaves on the 458 WM if buying a new rifle.

Is the Caprivi in 458 Lott still offered?

LHeym500,
Buy a donkey for taking care of that response to Wildcatter.
Well done.
At
https://www.kimberamerica.com/caprivi
the Caprivi .458 Lott is gone.
Good riddance !

quote:

Originally posted by Ready Aim Shoot:
How is the longer win mag throat going to work with-or seat out jacketed bullets? Like Wildcatter says, how is the short case going to stand up to max pressures using powders other than AA2230?

"Ready Aim Shoot"
is a recently new alias of member shootaway.
Writing flare of his post above serves to confirm this.
It is "a tale told by an idiot, full of sound and drooling, signifying nothing."
Ready Aim Shootaway doppelganger:



The .458 Lott is mustard on his biscuit, mmm hmm.

Worth repeating:

quote:

Originally posted by .458 Only:
... re the .458 Win Mag, even when loaded to maximum practical COL there is still more "free bore", or whatever it may be called, than the Lott when constrained to a COL of 3.6".

Never has there been an issue of pulling the bullets loose with the fingers! Just not possible when crimped into a cannelure either "home made" or one provided by Barnes in their TSX's or GS Custom. In the situation of a single-shot, as the Ruger No.1, they don't need a crimp as long as start pressure of each is the same.

As to actual psi, if the COL of the .458 Win cartridge is the same as the Lott, and the same amount of the same propellant is used under the same bullet, fired in the same length barrel, the psi of the .458 Win should be slightly less due to the longer throat (yes, even with the bullet seated "long"). And therefore, more powder could be used to bring psi equal to the Lott that should give better MV.

Bob
www.bigbores.ca

Buy a donkey Bob.
Yes, physics does not lie !
When the .458 Winchester Magnum was born, Winchester Arms had no long action.
They had to cobble a .30-06-length Pre-'64 action to shoehorn the more slender .300 H&H and .375 H&H into the M70.
With the M70 Classic circa 1990 the action had to be blocked down to continue short-changing the SAAMI .458 WinM. on magazine length,
even though it has a chamber longer than that of the .458 Lott.
Yes simple physics.
The .458 WinM. is the winner.

quote:

Originally posted by 416Tanzan:

quote:

trying to make a 2.5” magnum case produce over 6,000 ft/lbs of energy.

There is a way to do this, 6000ft# in a 2.5"case:

The .458 WinM. has won the war.
Peace-time play-time:



Short expander plug used, left a wasp waist on these circa 28K psi loads.

A 400-gr Woodleigh PP SN at 2500 fps (maximum recommended impact velocity)
and a 300-gr Barnes TTSX with the same powder charge
should be interesting,
whether with non-compressed AA-2230 or compressed H4895.
Custom preference: 450-grainer + 338-grainer

.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

quote:

Originally posted by RIP:

quote:

Originally posted by 416Tanzan:

quote:

trying to make a 2.5” magnum case produce over 6,000 ft/lbs of energy.

There is a way to do this, 6000ft# in a 2.5"case:

RIP,

Have you ever done any pressure-testing for this mission?

Seriously. Be careful.

—-Catter

quote:

Originally posted by Wildcatter:

RIP,

Have you ever done any pressure-testing for this mission?

Seriously. Be careful.

—-Catter

Why does he need to do pressure testing, he a very experienced reloader. Also he has great testing gear known as a brass case. For example, soften the case head with annealing the wrong way and work up loads and guues what, pressure signs show at a pressure that would be very low. So does someone with pressure equipment keep increasing the load because the pressure is low but primer pockets are expanding.?

Catter,
Page 206 has quite a bit of pressure trace discussion from The Maz and other published data. Quite enough to see that RIP is well within the limits of the Sane and Careful while using the tried and true working up of load methods most all re-loaders use. I would also be correct to note here, that anyone using the "work up" method in a .458WM has a far greater safety margin than in the 458 Lott. Why? Because of the THROAT in the 458 WM. Very forgiving and gradual in pressure increase. Not so much the short and abrupt SAAMI Lott Chamber.
Carry on.

Mike McGuire and Fury01,

Buy a donkey to you both for wisely advising Wildcatter.
The Maz has the outfit for pressure testing, as noted above.
Any pressure data he adds here is gilding the lilly.
We have had pressure data out the wazoo starting with General Julian S. Hatcher's AMERICAN RIFLEMAN article in August 1956:



Figures don't lie about the .458 Winchester Magnum, but liars have figured a lott anyway.



At least the SAAMI .458 Lott loads with 62,500 PSI MAP are useful for establishing starting loads for the .458 WIN+P+L.
A maximum SAAMI .458 Lott load at 3.6" COL may be fired in the SAAMI .458 Winchester Magnum chamber using 2.5" brass and 3.600" COL.
The pressure in the .458 Winchester Magnum will always be lower than in the .458 Lott.
Thanks to all the powder and bullet makers for the .458 Lott pressure data.
To the unrepentant deniers:



The deniers tried to cancel the .458 WinM. and got cancelled themselves. We just laugh at them now.
We know that the the .458 WinM. can do more than enough, even at 3.340" COL and </= 60,000 psi.

.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

Rip and fellow .458WM devotees;
Fall is here says the change in temperature, the birds and the field mice headed for the barn. Let's all make sure we take a 458WM out to the field this year and give it a chance to do what it does best. Whether 62K PSI Mono-metal modern Wonder bullets or 24K PSI cast bullet loads, no matter. Just take it out and report back. For The Mission.

Fury01,

That will be great for THE MISSION, buy a donkey.
Summer still lingers here, into the nineties*F yesterday, but it is leaving with a wimper.
Only 59% RH and near calm wind, a veritable blue bird day at the local shootin' range.
Average temp for my shooting yesterday was 87*F.

I took 7 loads, 9 cartridges each variety.
Shot 3 of each load over the 5-yard chronograph at 50-yard targets,
then went to 100 yards to do one-shot-group scope adjustments, looking for a 3-shot group at 100 yards,
to compare the POI of pairs of light and heavy bullets,
hoping for some useable Double-Bullet Regulation for my single barrel.

First idea was to try the Blackhorn 209 loads for .45-100-2.6" using two of my cast bullets closest to the 570-gr and 350-gr ones that Western Powders used.
Interesting results in the .458 Win'M. were obtained with the 25"-Barreled Ruger M77 Mark II.
My first 3 shots, from a clean and dry barrel, using the PC-painted FNGC,
I was concentrating "pretty good," but might have gotten a bit twitchy subsequently.
The 579-grainer at 1399 fps MV is very easy on the shooter's shoulder, much fun:



Above was done with the Nikon 3-9x40mm shotgun scope, no adjustments having been made since it was zeroed at 50 yards for the 407-grainer at 2170 fps MV.

Twitchier 50-yard results with the 373-grainer and a higher charge of Blackhorn 209:



Then the scope was adjusted for zero of the heavy bullet at 100 yards:



With same scope settings, the lighter bullet is landing about 4" high at 100 yards.



The maximum ordinate for that Lee hollow-base bullet is +4.09" at 89 yards, so that badminton-birdie-of-a-bullet is coming back down by 100 yards.
Shoots pretty good for a plinker at 100 yards,
will be dead-on at 158 yards, -4 inches low at 185 yards,
if BC is 0.250 for this 373-grainer.

I am estimating BC for the 579-grainer as 0.320.
Dead-on at 100 yards, maximum ordinate is +1.72" at 60 yards, it will be -2.87" at 125 yards.

Better than a 12-ga Foster slug !
Better than a super-magnum handgun for stunt-shooting elephants !
Almost as good as a hot-loaded .45-70 Govt. but with pressure level about 28K psi in the .458 Win'M.

That cloverleaf with the 579-grainer at 50 yards
was centered about 0.75" low (41.5 gr Blackhorn 209, 1399 fps MV),
with same scope setting used for dead-on, 50-yard zero of the 407-grainer (72.0 gr AA-2495, 2170 fps MV).

I reckon I will be trying more AA-2495 with the 579-gr/ 407-gr pair.
I did use AA-2495 exclusively for the rest of my DBR trials yesterday, with jacketed and monometal copper bullets.
I will be looking for an 8-pound jug of that AA-2495.
Blackhorn 209 is good stuff, but expensive, so Western Powders must be mighty proud of it !
To be continued, for THE MISSION ...

.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

RIP has an ideological twin.

https://bigborefan.wordpress.c...-vs-the-458-win-mag/

quote:

Originally posted by boom stick:
https://bigborefan.wordpress.c...-vs-the-458-win-mag/

boom stick,

Buy a donkey for that link to Bob's blog that takes us back to 2010.
That is an oldie goldie from long before the beginning of THE MISSION.

That is Part 2.
Here is part 1:

https://bigborefan.wordpress.c...8-win-mag-advantage/

And Part 3:

https://bigborefan.wordpress.c...8-win-mag-advantage/

Bob has been at it longer than I have,
yes, I am a chip off his ideological block, a pea in his pod.

I too finally figured out the .458 Win'M. beats even the .404 Jeffery, the first magazine-repeater DGR of 1905, and formerly the best DGR,
until 1956 when the .458 Winchester Magnum won the crown, and still holds it.

Le's see ... the .404 Jeffery was tops for 51 years.
The .458 Win'M. has been the winner for 64 years,
and there is still no challenger on the horizon.

.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

Alderella (Ruger M77 Mk II) did the cast bullet sampling Wednesday.
Bobbarrella did the jacketed and monometal copper bullets on same day.
Both have 25" Shilen stainless barrels of 1:14" twist, #5.5 contour on Alderella, #5 contour (slightly lighter) on Bobbarrella.



Bobbarrella can handle any scope imaginable with that DSS-2PP base.

.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

That’s about what I was expecting.
Perhaps the 75% rule has as much to do with the regulation of a double rifle - grouping both barrels together - as it does in predicting the point of impact.
Gibbs 461 sights are sometimes marked for two different bullet weights with two different powder charges and shoot both to the same point of aim at 100yds.

As it is, considering the majority of game one would pursue with the 458WM, I could see an open sighted rifle with a standing 100yd sight for the 450gr and a flip up sight for the 100yd 600gr load. Otherwise, one would have to up the load to get the heavy to shoot to the same sights as the 450.

What reticle does your scope have?
Maybe the 200yd picture would put the 600s right in there with the 100yd 450s.

Huvius,
Standard duplex on the Leupold 6X,
4-circle BDC on the Nikon 3-9X: That should be easy to find a sighting "schedule" to put on a range card for two bullets,
and a simple, close-range, memorized choice for each bullet.

To be continued with 400-gr & 300-gr 75% Rule trial.
Seating depth for both was about 0.33" when crimped on factory cannelures.

400-gr Speer FNSP
3.140" COL
72.0 gr AA-2495 ~100% to 101 % LR/filling >>> 2120 fps MV 87*F

300-gr Sierra PH-HP
2.950" COL
72.0 gr AA-2495 ~100 to 101 % LR/filling >>> 2199 fps MV 87*F

Surprisingly little velocity difference for 100 grains difference in bullet weights.
2120 fps with 400-gr Speer could be a Kangaroo Killer Load worth giving a workout,
when you get the trajectory hardwired.

72.0 grains of AA-2495: A 100% LR/filling "reduced load" with flat-based 400-grainer seated 0.33" deep and crimped tight.
No way that bullet will budge deeper or longer in the magazine.

AA-2495 is about same burn rate as H4895, but
burns more completely at lower pressures and lesser LR/filling.
Both are single-base, extruded powders.
H4895 works great when compressed,
not so with AA-2495, according to my personal anecdotes, so far.

.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

Maybe it is the drop of stock
for iron sights that the classic
double rifles and single-shot rifles have
that makes it easier to "double-bullet-regulate"
by the 75% Rule ?
Greater drop of stock will make
the heavier, slower bullets strike higher.
Maybe greater effect of barrel time
than with the lighter-recoiling, not-much-faster, lighter-weight bullets ?

quote:

Originally posted by RIP:
Mike McGuire and Fury01,

Buy a donkey to you both for wisely advising Wildcatter.
The Maz has the outfit for pressure testing, as noted above.
Any pressure data he adds here is gilding the lilly.

I've been overly busy with work and family lately, and am hoping to hit the range this weekend to gather some data. I was also kind of skittish of firing off so many of my low inventory of DGS bullets without any available resupply, but found some at CTD and replacements are inbound, so I am okay with sending them downrange now.

The Maz,
Understood. Buy a donkey for checking in at THE MISSION.
I need to get with domestic services mo'better, mo'often than I do.

Here is the last pair of DBR attempts last Wednesday.
The 3-shot 50-yard groups with the 400 Speer FNSP and 300-gr Sierra PH-HP were actually bigger than the 100 yard groups.
3 shots into about 2" for the 300-gr Sierra at 50 yards.
3 shots into about 1.75" for the 400-gr Speer at 50 yards.
I won't show those, but I will show the 4th shot with each bullet at same POA for both bullets at 50 yards,
1-shot POI showing the 300-grainer at 2199 fps MV is shooting about 1-3/8" higher than the 400-grainer doing 2120 fps MV, on 50 yard target.

I used up 4 more of the 300-grainers and 2 more of the 400-grainers, getting a semblance of zero for both bullets at 100 yards.
That left just 3 of the 400-grainers and 1 of the 300-grainers to get relative POI at 100 yards for the 2 bullets.



Due to the very low BC of the 300-grain PH-HP (0.145 at 2199 fps MV to 0.185 at 1744 fps at 100 yards),
it is now shooting lower than the 400-grainer (0.259 over its velocity range of 2120 fps MV to 1839 fps at 100 yards) ?

A 400-gr Woodleigh PP SN at 2500 fps MV paired with a 300-grain Barnes TTSX or TSX-FB at same powder charge might be better.

But I would say this is an OK load (about 1.5-MOA for 3 shots at 100 yards)
for duplicating a hot-loaded .45-70 Govt. with 400-grain Speer in your low-pressure .458 WinM:

400-gr Speer FNSP, R-P brass, F-215 primer
3.140" COL
72.0 gr AA-2495 ~100% LR/filling >>> 2120 fps MV 87*F

QL prediction:
MV ~ 2300 fps
Pressure ~ 46,000 psi
QL makes no allowance for throat.

RIP actual finding:
2120 fps MV
RIP pressure prediction:
~38,000 psi (RIP makes allowances for throat).

405-grain Remington FNSP might be mo'better in accuracy and tough enough for higher impact velocity.

.458 Winchester Magnum Perfection
In maxima potentia parvum spatium.
Id venit et vicit omnis.

Ron,

You are proving per the 416 Rigby/404 thread and recoil that you do not just shoot the 458 and similar for a few shots offhand at rocks and trees.

I was always the same as you but the average big bore owner does not shoot them a lot and much of the shooting will be "casual" style of shooting.

I'll mention in passing that I've developed two distinct bullet weight loads in my Tikka 9.3 x 62 that hit into the same group at 100 yards. It wasn't planned but just happened that way. They have about the same MV but the powders are distinct.

The 232gr Oryx: 63 grs RL-15 = about 2450 fps avg/ 5 into 1" at 100 yds. (Hornady brass + WLRM primers.

The 320gr Woodleigh: 66 grs RL-17 = about 2450fps avg and misses the 232gr Oryx group by about 1" (Hornady brass + WLRM primers.

That's an aside from the current topic, but it sorta serves as an example of what we might like to see in the .458 WIN.

Speaking of which (THE MISSION):

For anyone's interest: Testing loads for the 350gr Speer. My last post on that was a 72gr load of H4198/ 3 into 1.5" @ 100 yds. Avg corrected MV = 2527 fps.
Hornady brass, WLRM primers and COL = 3.26"

On Friday of this past week, I fired 3 more of that load for confirmation, with this distinction: COL = 3.12, crimped into the cannelure. I used the Lee crimp die on the former load.

Only two were fired on target on Friday: avg corrected = 2592 fps and a spread of 5.12" ! I fired the last of those three OH, seeing no reason to try for a group.

But that amply illustrates how a "simple change" of COL from 3.26" to 3.12" can drastically alter ballistics in both psi and poi.

Thankfully, I had another load for the bullet as well: 81 grs of H335 and COL at 3.26". They shot into 1.3" @ 2425 fps corrected to MV. But they were -6" below POA. I've made that correction and will give that load another try. I was aiming for 2400 fps with that load.

About recoil: According to math, the 72gr load at 2592 fps should be 46.8 ft-lbs less 15% due to Mag-na-ports = about 40 ft-lbs. (I've added this: the #1 Ruger empty with the Nikon 2-7 x 32mm scope weighs 10.3 lbs.)

The 81gr load under the same bullet (350 Speer) at 2425 fps should be 43.75 ft-lbs less 15% due to Mag-na-ports = about 37 ft-lbs. BUT!!! that's still 92.5% of 40 ft-lbs... In reality, however, it appears to the shoulder to be MUCH LESS that that!

The cause of that sense is that the recoil from a larger dose of much slower powder gave a much slower recoil, not as sharp as the faster powder. More of a stout push.

HEADS UP on this: These were all new, unfired Hornady cases. None of the loads were more than a "book load"> They were checked in several manuals. Yet on the first firing of the 81 grs of H335, I got a reading that I hoped for - exactly 2400 instrumental (add 18 fps for correction to MV). Before I put the empty back into the case, I always check the face of the case and primer. After all the shooting was done I examined the cases more thoroughly. That first case was split from .4" from case head for a total of .4" in length in a straight line on one side. Yet the case head expansion was normal (hardly any) for a once-fired case. All the others were normal. That was not a split/crack at the mouth of the case but in the body almost mid way toward the top.

I don't know of any others who may have had a similar problem with Hornady cases, especially in .458". I intend to inform Hornady. None of those loads were over 60,000 psi. And never have I had a similar situation from Remington or Winchester, even when the cases were well used.

Bob
www.bigborefan.wordpress.com

Internet mysteries and confusion - Not sure what happened, but www.bigbores.ca doesn't work anymore.

Must be Word Press who did it! It's now:

www.bigborefan.wordpress.com

Bob Mitchell