quote:

Originally posted by 4sixteen:
The action on my 375 H&H Magnum Zastava LKM70 Full Stock Carbine (now converted to 416 RM) is identical to the action on my 458 WM Remington 798. Whitworth, Interarms and Remington 798 actions should be the same Zastava action.

So your .458 Win. Rem-M798 has a 3.6"-long magazine box?
That is a treat! You have a .458 Winchester Magnum LongClaw!

They may all be the same basic Zastava Mauser action, same length action,
but it is a standard-length M98 size just like all the Pre-'64 M70 actions were all 30-06-length.
The Winchester factory opened them up to fit .300 H&H and .375 H&H, in the old days of New Haven, CT.

The two Whitworth .458 Win. rifles I own were not opened up to .375 H&H length, came as 30-06 length.
One of them I misguidedly paid a gunsmith to open up to barely fit a .458 Lott.
That was before I "wisdomed" that a .458 Win. is better than a .458 Lott!
But, hey! A .458 Lott with residual .458 Win. throat is not a bad thing.
It allows one to seat those 400-gr HV bullets deeper in the case,
and do the same 2500 fps.

Every one of the half dozen Whitworth .375 H&H rifles and actions I have were all opened toward the front of the action at the factory.
Re-barreled or re-chambered to: .340 Wby, .358 STA, .375 Wby, .416 BS, .450 BS.

I got all that out of my system before the Charles Daly and Remington Zastava rifles came and went.
If I had only known the Remington M798 .458 Win. rifles
were done on actions already opened to .375 H&H length, at the factory ... sigh ...
And I should have kept at least one of those Whitworths unaltered.
Alas, the last of them is being rechambered from .458 Win. to .458 WinRuger.

The Gunsmith said the multiple rings in the chamber were not due to my modest loads of AA-5744 with cast bullets, even if I did use filler.
I will not do that again with AA-5744, just no need for it.
It shot better without filler than with filler anyway.

Rip ...

It will be interesting to see if Les's new Whitworth .458 Win. has the 3.4" action left as original, or has it been opened up to 3.6" at the factory?

Rip ...

The Interarms Mark X Alaskan and the Witworth Express 458 Win I had were set up as standard length actions. IE 3.4"

CTF,

Thank you.
That is 4 out of 4 left as 3.4" in this poll of Interarms/Whitworth/MkX .458 Win. factory rifles/barreled actions.
Will Les make it 5 out of 5?

Rip ...

Allrighty, then...what exactly do I measure? Magazine box interior?

quote:

Originally posted by RIP:
Gustavo,

Thanks for supporting THE MISSION.
400-grain HV testing in Alderella is pending.
And the Iron WaterBoard Buffalo needs to be rounded up from pasture to catch a few 450-grain FN solids at 2350 fps,
and compare that to other super-penetrators I have known.
20" barrel? Moi?
Sorry, this birdman is not into fads.

God bless THE MISSION Watcher!!!

Personally, I would like to tryout a 16.5" barreled 458 Win with a Harrell's brake on it. It would boot 350 gr TSX out at about 2350 fps possibly 2400 fps. Would make a dandy berry picker special.

quote:

Originally posted by Gustavo:

quote:

Originally posted by RIP:
Gustavo,

Thanks for supporting THE MISSION.
400-grain HV testing in Alderella is pending.
And the Iron WaterBoard Buffalo needs to be rounded up from pasture to catch a few 450-grain FN solids at 2350 fps,
and compare that to other super-penetrators I have known.
20" barrel? Moi?
Sorry, this birdman is not into fads.

God bless THE MISSION Watcher!!!

Amen ! Or x2

quote:

Originally posted by Les Staley:
Allrighty, then...what exactly do I measure? Magazine box interior?

That will do, should be about 3.4" long inside the box, parallel to bore axis,
with no filler/blocking off of the back of the magazine.
Send me a PM for further discussion if you get any pictures for posting, please.

Rip ...

John "Pondoro" Taylor liked a 25" barrel and a scope on a +.40-cal rifle, magazine repeater.
Open-sighted double rifle with 26" barrels.
He was not a metrosexual, even if he was gay.

What a post to start page 64!

Rip ...

4.415" inside mag box at bottom. No filler. Took a few pics just now, but a little to early..sun not shining on deck yet. Another cup of joe oughta do it.

Les,

Did you mean 3.415"?
If so, that makes it 5 out of 5.

Nice, solid steel box, eh?
Integral to bottom metal.
No sheet metal needing reinforcement in the front.

Rip ...

Yeah, Ron..3.415". Another cup of joe might do it! No fillers, just cold blued steel. Pm sent. I see you got the pm. Thanks.

Length of the magazine across the bottom is about 86.5mm or 3.4" on my 458 WM Remington 798. About the same as on my 416 RM Zastava that was converted from 375. Used a 30-06 round to hold the floor plate back to take the photos. See the 30-06 is good for something in the sporting world.

4sixteen,

So your .458 Win. action is 30-06-length too, like Les's, CTF's, and mine.
Strange that your .375 H&H would be shortCOL also.
I am going to have to dig out some of mine and measure them.

All of the H&H-length Zastava actions should have been opened up to about 3.62" from about 3.42" and the opening up seems to be all forward in the action,
on the ones I have seen.
The Pre-'64 M70s did it better opening mostly to the rear.
My .300 H&H/.375 H&H/.395 H&H/.458 Winchester Magnum switch barrel is in the works.
Alderella may weigh 9.0 lbs, but the Pre-'64 will be about 7.0 pounds dry. less than 9.0 pounds field ready, scoped, loaded,
and with a muzzle brake: 1-pound stock (instead of 2.5-pound) and a No.4 sporter (instead of "medium varmint contour): That ought to take 2 pounds off.
Same sights as on Alderella, and this time the Gunsmith will pop the pimple on her nose before she comes home.
"Aphrodite" will be her pet name.
4 barrel rig to put the Blaser to shame: There is no .395 H&H Blaser in the whole wide world, you betcha!

Rip ...

Here she is lounging on Les's deck, right at home:

Had a little session with the New Girl in Town this afternoon. She's a aweety! Shot two three shot groups at 50 yds. Both groups about six inches high with the 100 yd blade. Also working with a couple trial loads for my new 35 Whelen. The Whelen is built on a 1940 Oberndorf 98 German Mauser. Quite a difference in the length of bolt throw. The Oberndorf doesn't come back near as far as the Whitworth, and the Whitworth is shorter in the feed ramp, for sure. (Lengthend toward both front and back). I'll take some pictures of the differences when I get a chance. And thank you, Ron, for posting my pictures

Does that say "Cal. 458 Win. Mag." in cursive script on the left side of the knoxform?
Mine said only "Cal. 458 Win." Did factory do some extra decoration there?



Pretty thing.

What is her name?


Rip ...

Ron, if you'll be her Godfather, I'll name her "Pretty Thing"

OK, gladly, godfather to "Pretty Thing Whitworth."
Proud I am.

Rip ...

Here is my chambering designation:



Afraid that is going to have the word "RUGER" stamped in a new line above the word "Win."
*********************RUGER
**************Cal. 458 Win.
To designate ".458 WinRuger" re-chambering.

Rip ...

Rearward throw of bolts about the same but different shaped rear receiver bridge. No clip slot on Pretty Girl, confused me for a minute. Feed ramp also different shape, picture on the way. Feeds everything I've tried slicker than a snotty doorknob.

OK, awaiting incoming, this is great for THE MISSION.

Rip ...

High polish and no purple-blue receiver on Les's
.458 Win.:

Highly polished feed ramp too!

And the .35 Whelen Oberndorf Mauser:



If not such a great chambering, it would make a nice .458 Win.


Rip ...

quote:

Originally posted by RIP:

Really sweet, it looks brand new. I had 2 of those in 375 and 1 in 458.
One of the 375s looked almost as nice as yours.
One thing I will say , all 3 of mine were Very accurate. Course my eyes were younger back then .

CTF, it hasn't been hunted or shot and looks like it. Has little marks from bumping other guns in a safe, but you have to look for them. Our local elephants are staying out of sight, (they prolly heard about my new gun).

Ron, it's righty tightly, lefty loosely, right? Barrel could be changed to 458 easy enough, but with the P***Elm King and Pretty Thing, I'm covered. If I wear these two out, I'll drop back to my CZ 550 375 H&H.

One thing I love with the 458 . For N.A. anyway a 500 gr cup and core soft nose will do most things a guy needs. Kinda boring , I know. But it will flatten a charging brown bear and poke a hole thru a seers ribs with about 0 blood shock. The deer will run 20-30 yards and collapse.
One of the better shots I made with my Witworth 458 was on a nice big doe Sitka Blacktail on Kruzof Is. Shot her thru the brain at around 115 paces with the express sights and a Winchester 510 gr big blue round nose soft nose.
I couldn't get my baby finger in the entrance hole and barely in the exit hole. She was left side quarter to me but a bit more broadside than full quarter. I took a quick kneeling top of the head shot.
When I walked up to her , for a minute I thot I had missed. And the air shock wave had knocked her out. Then I saw a drop of blood just below my aimpoint.
I've killed more than 15 deer with the 500/510 gr factory loads or equivalent hand loads. Didn't loose 25 lbs of meat to bloodshock combined total.

Above is a photo of a 458 Win Mag case with a 500 grain Nosler Partition seated by softly chambering the round so that the rifling pushed the bullet into the case, thus giving the OAL of the cartridge for the bullet seated just touching the rifling. As shown, the OAL is 3.473". This is slightly more than 1/10" more than cartridge seated to cannelure and it amounts to about a 7% increase in powder capacity. So if I machine (have a gunsmith machine) out the spacer at the back of the magazine, the magazine dimension increases to 3.57". So there is very little to be done to the rifle to increase the performance. I think no change will be needed for the ejector blade since the only issue would be if loaded rounds were being cycled, which if shooting at something, would not be the case.

There are two issues, 1. with full profile round nose bullets the bullet contacts the rifling further forward, so there would be a shorter OAL. and 2. I need to go back to the drawing board for load development since the longer OAL results in significantly more case capacity, meaning the present loads would be less than potential, so re-working will be necessary. Not a bad problem to have.

Excellent results with the Hornady 500gr at 2000 fps MV from my 458 WM at close range on Moose that produce 1 shot dead right there kills. Going to give the 350gr TSX a try at 2575 fps MV. At 150 yards for example this bullet has a 400 fps advantage over the 500gr. For greater downrange shock.

Thanks for the "Practical Dope on the Big Bores" guys.
It puts F.C. Ness's 1948 book to shame. Of course the pickings were slim back then, before the .458 Win. had won the game fields.

Forging on to page 459 ...

Here is one of 4sixteen's pictures doodled on in attempt to illustrate how the Mark X Mauser is opened up to .375 H&H length:

So the Zastava factory whittles on the bottom metal hinge area a little,
they cut off the strong integral front of the box and weld a sheet metal extension onto it, then they whittle on the feed ramp,
and make it all fit together.
I had a straight factory Whitworth .375 H&H re-barreled and re-stocked to make a .358 Shooting Times Alaskan.
Cerakoted a sort of olive drab color, Brown Precision bare fiberglass stock painted by me with Krylon from Walmart.
The stock could always be sanded and re-painted.
Consider it primer-painted:

All tight and thoroughly functional.
I guess there is enough steel left to lock the lugs.

Shortened feed ramp for lengthened box on a standard M98 length action.

Somehow it got engraved instead of stamped for the chamber specification: