Project Goal: Ruger No1 in 460WBY for Speer AGS Tungsten Solids

[Riflecrank]

So what do I need to use to clean up the Lott throat and make it more powerful than the WM without changing the chambering?
I'll not deny that my Lott has a short throat. I've proven it to myself with the dual cannelure Speer bullets.

I think I understand the fundamental confusion.
The jackals (Jack L worshippers) will not admit that the simple SAAMI .458 Winchester Magnum chamber can be loaded to same or LONGER COL than the simple SAAMI .458 L chamber.
All it takes is a long enough bullet, same bullet in both chambers, at same COL and same pressure,
and the non-SAAMI-handloaded .458 WM+ beats the hottest SAAMI-satisfying .458 L load,
that can be concocted with any choice of powder charges selected as best in each cartridge.

The .458 WM+ and .458 L will have identical net case capacities.
Might have to select a little bit faster powder for the .458 WM+
or more of the same powder as used in the already compressed charge of the SAAMI .458 L.
The longer leade in the simple SAAMI .458 Winchester Magnum chamber allows this,
by pressure let-off or in effect increasing the effective net case capacity.
THROAT THROAT THROAT.
This will not just equal the SAAMI .458 L for MV at 62,500 psi,
but truly open a can of MV whoop-arse at same 62,500 psi MAP.
The .458 WM+ handload in a simple SAAMI .458 Winchester Magnum chamber simply wins.

 

[Forrest Halley]

All it takes is a long enough bullet, same bullet in both chambers, at same COL and same pressure,
and the non-SAAMI-handloaded .458 WM+ beats the hottest SAAMI-satisfying .458 L load,
that can be concocted with any choice of powder charges selected as best in each cartridge.

The .458 WM+ and .458 L will have identical net case capacities.
Might have to select a little bit faster powder for the .458 WM+
or more of the same powder as used in the already compressed charge of the SAAMI .458 L.

So with all this apples to oranges comparison I just have to ask, do you have a 6.5 Creedmoor?

So what can be done to a .458 Lott chamber to allow it to have a better lead and run faster at lower pressure? Clearly with a longer case and a proper throat it will surpass the .458 WM+P. So the question is how to achieve this with the longer case?

 

[Riflecrank]

Forrest Halley,
For what it is worth, yes, I have several 6.5 Creedmoor rifles.
I like the throat on that cartridge too.
For .264-caliber, parallel-sided-free-bore is 0.2645" in diameter and 0.1992" in length,
with 1*30'00" leade hemi-angle or 3-degree cone angle of leade.
By comparison, the SAAMI .458 L,
for .458-caliber bullet, parallel-sided-free-bore is 0.4590" in diameter and 0.1780" in length,
with 2*00'00" leade hemi-angle or 4-degree cone angle of leade.
Ouch.

A throat for .458-caliber bullet that is proportionally like the 6.5 Creedmoor would have
PSFB length =( .458/.264) x (0.1992") = 0.3456"
That is about twice the length of parallel-sided-free-bore as found in the SAAMI .458 Lott.

The 6.5 Creedmoor-proportional PSFB diameter for .458-caliber bullet = [(.458/.264) x (0.0005")] + .4580" = 0.4589"
Well the SAAMI .458 Lott has PSFB diameter specified as 0.4590", close enough.
A dangerous game battle rifle having a plus-tolerance in throat is not as bad a thing as in a varmint rifle of small caliber.

Then the SAAMI .458 Lott has an abrupt leade of exactly 4 degrees cone angle.
The SAAMI 6.5 Creedmoor leade cone angle is exactly 3 degrees.
The SAAMI .458 Winchester leade cone angle is the entire throat and it is very close to 1 degree.

The .458 Winchester Magnum is a "Smooth Operator."

The silly thing about the SAAMI .458 Lott is that it has brass that is 0.3" longer than the .458 WinMag, but is commonly used in a magazine that is only 0.2" longer and limited to COL of 3.600".
The bullet manufacturers had to start making bullets with shorter noses to serve the .458 L.
The old ones for the .458 WM were too long in the nose.

How to improve the .458 Lott ?
Use it in a single shot and tack on the .458 WinMag throat like it was on the original C.I.P. homologation, which was a total waste and handicap for a bolt action limited to .375 H&H length.
Similarly the 3.0" case length is a total waste unless used in a single-shot.

 

[6.5 wildcatter]

Part of the problem with the concept of the 458 Lott as a means to improve 458 WM ballistics is the retention of a longer, but still straight wall case. This approach doesn’t yield sufficient increase in case volume while limited by the 3.6” magazine length in an otherwise unaltered LA bolt rifle. The expedient of using longer than 3.6” COAL cartridges defeats the purpose of a DGR repeater.

Another alternative approach is to use a bottleneck case of sufficient body diameter to meaningfully increase case volume while preserving the COAL limitations of a standard LA magazine. Case in point is the use of a 404 Jeffery case, very minimally shortened, and necked up to accept 0.458” diameter bullets. To wit, the 460 G&A. I belatedly re-discovered this cartridge about 2 years ago, while searching for an intermediate alternative to my RSM in 450 Rigby Rimless Magum and the 458 WM in a tang safety Ruger M-77. Riflecrank was instrumental in providing source references on original loads and cartridge specs as I set out to implement a plan that would result in an Africa-ready DGR. The flawless and expedient work by Gene Simillion resulted in a true elephant rifle.

By using the 404 J case and fitting a magazine with appropriate cartridge stack geometry - Gene’s design and execution - 4 cartridges fit and feed flawlessly in the mag box of a Win M-70 CRF Classic - though the same configuration would work in a Pre-64 M-70 - without the need for an aesthetically unpleasant drop-belly stock.

The end result of a 460 G&A is a cartridge that can be loaded with close to 100 grains of appropriate burning rate, uncompressed powder. My own load in a 23” barreled M-70 Classic is 89 grains of powder with a CEB 500 grain monolithic Safari Solid for 2400 FPS. I opted for this load, rather than a heavier one, because it reliably traverses elephants and energy expended on the air and trees beyond seems superfluous and only produces more recoil but not greater killing power.

Just my 2 cents in adding a bit more confusion to the mix. I have nothing against the 458 Lott - had an RSM in that chambering for several years and liked it - but getting more than 2300 FPS from it was a chore . For the size and weight of an RSM, great DGR that it is, a 450 Rigby Rimless cartridge, my current version, seems its natural expression. Attainable MV in this configuration is only limited by the shooter’s thirst for recoil.

Better home for the 458 WM IMHO is a Ruger Hawkeye African, or if the 458 WM+ is preferred, the same rifle with a slightly lengthened bolt throw and mag box, as described by Dave Scovill in Handloader magazine, issue #119, January 1986. A fairly simple modification yielding 3.6” COAL and maximizing the straight-wall case-lengthening concept while retaining the bolt action repeater feature of a viable DGR.

 

[Riflecrank]

For a bolt-action rifle of only .375 H&H magazine length, the best option is to simply use a SAAMI .458 Winchester Magnum chamber reamer on a virgin barrel.
But if that barrel has already been de-flowered to .458 Loser with 2.8" brass and shortie-tightie throat,
then use that same .458 Winner reamer to extend the throat.
Then call it the .458 Watts Express.

Ideally I would start with a new reamer for 2.7"-length brass superimposed on the SAAMI .458 Winchester Magnum chamber, use it in .375 H&H action length.
I would call that one the .458 Watts Winchester II.
.458 WWII.
WWII-era origin for the .450 Watts Magnum, incubated from 1939 to 1949.
Gestation interrupted by WWII.

Consider:
The SAAMI .375 H&H chamber has a wide-based, leade-only throat.
Base diameter is 0.3900" with abrupt cone angle of 4 degrees, hemi-angle of 2 degrees.
Groove diameter = 0.376", and Bore diameter = 0.366" according to SAAMI.
Bullet diameter is max 0.3760" with minus tolerance of 0.003": 0.373" to 0.376" allowed by SAAMI.

Thus a 0.375 bullet launches into a 0.390"-wide cone and travels 0.344" in the throat run to bore diameter for full engraving at the end of the leade.

By comparison the SAAMI .458 Winchester Magnum launches into a tighter base both absolutely and relatively.
No sloppiness there.

.390" - .375" = +0.015" for the .375 H&H

.469" - .458" = +0.011" for the .458 WM

No flies on the SAAMI .375 H&H.
No flies on the SAAMI .458 Winchester Magnum throat.

 

[Riflecrank]

Well said 6.5 wildcatter.

But the simple SAAMI .458 Winchester Magnum in 3.4" magazine length and 24" barrel easily does
2200 fps at 3.340" COL with 500-grain bullets, even the TBSS an FN, bronze-jacketed, bonded-lead-cored "solid."
If you want to load to .458 WM+ levels, the 500-grain TBSS can do 2400 fps at 3.550" COL in a 24" barrel.
I have tinkered with wildcats and proprietary rimless (.450 Barnes Supreme, .458/.416 Ruger, .458/.338 Lapua, .450 Dakota, .460 WbyMag) and rimmed/flanged carts too, but the ease and flexibitity of the
.458 WM loaded to .458 WM+ wins for all practical purposes,
except the "my cartridge is longer than yours" purpose.

Funny how the jackals start howling when the .458 WM+ is loaded longer than a .458 L can handle.

 

[6.5 wildcatter]

Riflecrank,

agree with your assessment of the 458 WM capability in standard LA 3.340” mags. In my case I’ve adopted the practice of using CEB 450 grain monolithic Safari Solids in the 458 WM case at close to 3.39” COAL with ball powder charges, reducing compression and retaining repeater capability. I reserve the same bullet in 500 grain weight for the larger capacity 45 caliber cartridges, 450 Rigby Rimless and 460 G&A.

I’m an irredeemable wildcatter loony so one-off cartridges and reloading are my stock in trade!! Go figure. Cheers!!!

 

[adamsredlines]

Well this was a fun thread to come back to! Went about as expected….it started off well then…well, here we are. I don’t understand needing to justify a rifle. I’ve got plenty in my safe that I may shoot very little, or not at all, or some when I first get them….but they’re all neat in their own way regardless of practicality. I’m pretty much set to do most anything a guy can do with a firearm, but still enjoy them and get hairbrained ideas. I’ll probably end up with a few more Ruger No 1’s just because I like them. I’d like one in 375HH and 416 Rigby to go along with my .458 (whether it be Lott or Weatherby).



I knew Weatherby had a bad wrap around here, but had no idea that Lott was so hated by many. I think Jack Lott is living rent free in some of your heads for no reason at all. Its an inanimate object and people are getting their feelings hurt? I’ll also say that most cartridges are just incrementally better/different than another. That’s why there’s more than 3 or 4 cartridges out there…pick what you like for whatever reason and roll with it. As far as hotrodding 458WM to outperform 458 Lott…sure, you can…but also those techniques could probably be adapted to the Lott and achieve higher velocities too. That seems like the whole 9m vs .45ACP argument that “modern 9mm projectiles are so good” but they always compare them to dated 45ACP. At the end of the day, modern technology applied to both, the 45 will still poke a bigger hole.



As far as SSK Industries goes, I reached out to them several years ago inquiring about this very project and they said no. I tried to ask why, and all they just repeated “we do not provide that service”. I wasn’t trying to change their mind, just wondered what the issue was, and they were disinterested in further discussion, so I wrote them off as a company.



The dream continues I suppose....

 

[TOBY458]

Well this was a fun thread to come back to! Went about as expected….it started off well then…well, here we are. I don’t understand needing to justify a rifle. I’ve got plenty in my safe that I may shoot very little, or not at all, or some when I first get them….but they’re all neat in their own way regardless of practicality. I’m pretty much set to do most anything a guy can do with a firearm, but still enjoy them and get hairbrained ideas. I’ll probably end up with a few more Ruger No 1’s just because I like them. I’d like one in 375HH and 416 Rigby to go along with my .458 (whether it be Lott or Weatherby).



I knew Weatherby had a bad wrap around here, but had no idea that Lott was so hated by many. I think Jack Lott is living rent free in some of your heads for no reason at all. Its an inanimate object and people are getting their feelings hurt? I’ll also say that most cartridges are just incrementally better/different than another. That’s why there’s more than 3 or 4 cartridges out there…pick what you like for whatever reason and roll with it. As far as hotrodding 458WM to outperform 458 Lott…sure, you can…but also those techniques could probably be adapted to the Lott and achieve higher velocities too. That seems like the whole 9m vs .45ACP argument that “modern 9mm projectiles are so good” but they always compare them to dated 45ACP. At the end of the day, modern technology applied to both, the 45 will still poke a bigger hole.



As far as SSK Industries goes, I reached out to them several years ago inquiring about this very project and they said no. I tried to ask why, and all they just repeated “we do not provide that service”. I wasn’t trying to change their mind, just wondered what the issue was, and they were disinterested in further discussion, so I wrote them off as a company.



The dream continues I suppose....

That must’ve been after JD Jones retired from SSK. The new owner has all but discontinued any kind of custom work. I guarantee JD has done much more radical projects than a simple conversion to 460 Weatherby.

 

[adamsredlines]

That must’ve been after JD Jones retired from SSK. The new owner has all but discontinued any kind of custom work. I guarantee JD has done much more radical projects than a simple conversion to 460 Weatherby.

It's possible, I just thought it was odd they wouldn't even discuss reasons. Safety? Capabilities? Was it caliber choice? Don't work on Rugers? Just don't wanna? Oh well.

 

[Flewis]

It's possible, I just thought it was odd they wouldn't even discuss reasons. Safety? Capabilities? Was it caliber choice? Don't work on Rugers? Just don't wanna? Oh well.

You should build exactly what you want. No one but you has to agree. The number one has been built too at least 600 nitro, so have at it.

 

[Riflecrank]

.620/.577 NE by American convention is the only "600" on a Ruger No. 1 that I have heard of.
Has been done on .577 Snyder case too, same rim size.
Funny thing is that by British convention it would be called a 577/600 NE, so the confusion is understandable.

NECG might have actually made the 20-gauge rim work in a Ruger No. 1, but they have quit doing it.
I am guessing the thinning of action parts was too much for even the ultra-low shotgun pressures.
Too many problems with the ones they have built ?

SSK is indeed a shadow of what it used to be.
But I would expect any gunsmith worth his salt to refuse the job unless he got to measure the dept of those three holes over the chamber before widening that chamber underneath those holes.
Where is an integral quarter rib when you need one ?

Hey, I am the dumb bunny with more than two dozen wildcats to my credit.
Even got Harry McGowen to agree to making my very own caliber of barrel: .395.
It used to be listed at McGowen Barrels even after he sold the company.
No longer offered, after only 9 barrels of .395-caliber were sold, 6 of them to me, heh-heh-heh.
Got Dave Manson to make custom reamers.
Might be 9 rifles of .395 caliber in the world, 5 different chamberings of my unique .395-caliber wildcats.
Six of the .395 rifles are mine.
Two of them are chambered for the .395 Tatanka, a .395/.416 Rigby-20-Degree-Shoulder.
One of those is a Ruger No. 1, heh-heh-heh.

Quality Cartridge was still listing .395 Tatanka and .500 Mbogo properly head-stamped brass last time I looked. I claim both. Just necked up Dave Estergaard's .470 Mbogo for the latter.
I may be the first guy in the world to have killed a cape buffalo with the .500 Mbogo.
It has been all downhill since then.

So yes, the more rifle chamberings the merrier.
But I do love to hear the jackals howl.

 

[Wyatt Smith]

I have read for a long time that the best 458 Lotts were built off of 458 win mags that were converted.

 

[DrBob]

Well, that's my goal. I have a Ruger No 1 in 458 Lott and love it, but kinda want a bit more horsepower. It's a novelty for sure. I also have 50 of the African Grand Slam Tungsten core 500gr Speer projectiles that I have been saving for this project.
I've seen Rugers rechambered to 460 Weatherby, but have been unsuccessful in finding a gunsmith to perform the work to my rifle. The ones I've seen have been the blued/walnut variety which is pretty, but I like the tropical versions better.

So, anybody have recommendations on who in the states can do the conversion? It would have to be rechambered and the extractor work done.

View attachment 584387View attachment 584388View attachment 584389

Well, that's my goal. I have a Ruger No 1 in 458 Lott and love it, but kinda want a bit more horsepower. It's a novelty for sure. I also have 50 of the African Grand Slam Tungsten core 500gr Speer projectiles that I have been saving for this project.
I've seen Rugers rechambered to 460 Weatherby, but have been unsuccessful in finding a gunsmith to perform the work to my rifle. The ones I've seen have been the blued/walnut variety which is pretty, but I like the tropical versions better.

So, anybody have recommendations on who in the states can do the conversion? It would have to be rechambered and the extractor work done.

View attachment 584387View attachment 584388View attachment 584389

Don't. No need to rechamber. The 458 Win Mag will tolerate handloads to 3.6 inches... the length of the Lott. I did it and it was published in ZA's Magnum Magazine. Pressure traces and all. No need to do this unless you really want to. The chamber of the 458 is cut with ample room... I first tried the extended length with my No. 1-H Tropical and then with a CZ 550 and Winchester 70 with 375 H&H parts to give magazine, bolt stop and ejector up to full length. You cannot use Lott brass as the chamber is cut for 3.34 inch brass. I'll be glad to share the loads I made for mine as a reference for safety concerns. I used powder equal to Sochem for the article. Spoiler alert.... 500 grain bullet are great with Varget.

 

[DrBob]

Here is the article..Be safe.. work up loads...

 

[DrBob]

The recoil is going to be severe in the Ruger. Too much of a "good thing" is bad for the brain. Dead is dead.... "deader" is still just dead.

 

[DrBob]

The largest cartridge(physically) chambered by Ruger in the Number One is the 450/400 nitro. A few were chambered in the similar 450. nitro.

There is a reason for this, anything larger than the 450/400 or the 458 lott requires removal of a lot of metal from the action as well as the chamber portion of the barrel.

I would leave your number one alone. The 460 is a very large high pressure cartridge. There is nothing to be gained by pushing your luck and devaluing a nice and rare rifle.

Your tungsten core solids will go through any animal alive out of the 458 Lott.

Are you planning on whale hunting or shooting armored personnel carriers?

If so just get a proper 50 BMG.

Hamilton Bowen made a few No. 1 in 470 NE. It required certain production series because of the metal issue. I have one of his conversions. LaBonte did the reboring. So, in certain No.1 the top end is the 500/470. Frankly, with the killing power performance of modern bullets and knowing how over-promoted the velocities were for the original African cartridges.... no need to punish the human body more. Boddington only mentioned one time that a 460 Weatherby made a difference and that was in a 100 yard shot on a big elephant.

 

[Riflecrank]

DrBob,
DrRon here. You have done an excellent piece for manMAGNUM.
We at another forum call your .458XL by another name, .458 WM+.
Finn Aagaard first tipped off many of us to think of the possibilities
in his March 1984 AMERICAN RIFLEMAN article called "THE .458 WIN. MAG."
He used IMR-4320 and an otherwise unspecified 500-gr bullet loaded to 3.600" COL and said
"... I was able to get 2250 fps with apparently safe pressures."
Finn apparently was using a factory Winchester M70 of the pushfeed type with 22" barrel, same as Dirty Harry used as a night-ops, counter-sniper rifle from church roof in downtown San Francisco.

Nowadays, we of the Square Table just make sure our .458 WM+ rifles are properly chambered to SAAMI/CIP (same/same) chamber & throat specs,
that the groove diameter is 0.458" to 0.459" (0.450" bore),
that the twist rate is 1:10" to 1:14",
and just go to town using the maximum loads for a SAAMI .458 Lott as our starting loads.

A most interesting feature of your article is this pressure trace for the .458XL:

Could this be for the 500-gr Barnes Banded Solid at 2300 fps ?
Or was it that cape buffalo (one shot and done) load you mentioned, 450-gr TSX at 2475 fps ?
And what powder, please ?

 

[DrBob]

DrBob,
DrRon here. You have done an excellent piece for manMAGNUM.
We at another forum call your .458XL by another name, .458 WM+.
Finn Aagaard first tipped off many of us to think of the possibilities
in his March 1984 AMERICAN RIFLEMAN article called "THE .458 WIN. MAG."
He used IMR-4320 and an otherwise unspecified 500-gr bullet loaded to 3.600" COL and said
"... I was able to get 2250 fps with apparently safe pressures."
Finn apparently was using a factory Winchester M70 of the pushfeed type with 22" barrel, same as Dirty Harry used as a night-ops, counter-sniper rifle from church roof in downtown San Francisco.

View attachment 592879
View attachment 592880

Nowadays, we of the Square Table just make sure our .458 WM+ rifles are properly chambered to SAAMI/CIP (same/same) chamber & throat specs,
that the groove diameter is 0.458" to 0.459" (0.450" bore),
that the twist rate is 1:10" to 1:14",
and just go to town using the maximum loads for a SAAMI .458 Lott as our starting loads.

A most interesting feature of your article is this pressure trace for the .458XL:

View attachment 592878
Could this be for the 500-gr Barnes Banded Solid at 2300 fps ?
Or was it that cape buffalo (one shot and done) load you mentioned, 450-gr TSX at 2475 fps ?
And what powder, please ?

Dear DrRon: Thank you for your posting about the .458 WM+! I will gladly file this under "nothing new under the sun" or "brilliant minds think alike". Johan Loubser recommended the powders of which one matched Finn's selection with the IMR 4320! Living in Alaska, I have gravitated to the Hodgdon Extreme powders since their temperature insensitivity made working up loads easier for any climate. The 450 gr with Benchmark turned out to be very potent and was the round that dropped the buff. I can't remember what bullet/load was with that curve, but the "uniformity" column with lower numbers would be a better fit such as a "1,1,1". The 500 grain Barnes is "1,2,1" with A-2520.

The most important point for me was using the pressure curves to prove the relative safety of the loads.... putting a tangible number to the loads.

The Barnes banded solid saved my bacon. Just as I squeezed the trigger the buff started to quarter away and instead of the bullet striking behind the shoulder it passed forward into the brachial plexus and carotid artery area. A conventional bullet design and a slower velocity might not have downed the animal in one shot. With the buffalo dead, I had the chief tracker put my 450 grain TSX round in his Ackley and fire it at 10 feet into the front quarter. The bullet was recovered in the back of the paunch, missing only one petal although slightly mushroomed. That is a tremendous stress on any bullet.

Benchmark with lighter bullets and Varget with the 500 and 550s would be my best initial recommendation.... but since publication additional temp insensitive powders are available. I will try to find Aagaard's article. It was fun (well $$$$) working up the article.

Best regards,

DrBob

 

[TOBY458]

I have a Blaser R8 in 458 Win Mag. It has a magazine length that will accommodate the 3.6” loads of the 458 WM+. Last year I used this rifle to hunt buffalo and elephant. I was using CEB 420 Raptors and 450 Solids. With the Raptors, I loaded those to standard seating depth and used the plastic tips. This allowed for more aerodynamic bullets which afforded me an additional 150 fps impact velocity at 50 yards. This was tested by @michael458 in his lab. With the solids, I loaded those out to the last band on the bullet, which allowed me to use a bit more powder than standard loads, but not full Lott loads. My loads were doing 2275 and 2210 between the 420 and 450 gr bullets. The Raptor load absolutely flattened the buffalo I shot. Internal damage was massive. I only wish we had ran across a suitable tuskless elephant to try the solids on.