10
Jun
09

heavy big bores – .458 calibers

The .45-70 Government

The pic above, on the header, is my Ruger No.1 in .45-70 Improved. That is, the throat has been extended by .30″ by a world class gunsmith. The cost was $75 nearly a decade ago, and was well worth it. I formerly owned a used Ruger No.1 in .45-70, that was in excellent condition, that allowed the 500-grain Hornady Interlock to be crimped into the cannelure with still some “freebore”. The second Ruger No.1 was new, off the shelf of a gun dealer, and had a shorter throat which made it somewhat difficult to crimp into the cannelure without bumping the rifling. So, I had my smith remove .30″ of the rifling for two reasons: as mentioned, 1) to allow more freebore, and 2) to allow seating bullets “out” by .25″ if the bullet was long enough to permit it with the case still having a solid grip on the bullet. That allowed a COL of 3.19″ for the 500-grain Hornady and 3.21″ for the 450-grain A-Frame.

Before we get too far ahead of ourselves, let me briefly explain the “crimp” into the cannelure of the Hornady previous to having it “long-throated”, or “improved”… With the compressed load I was using behind the 500-grain Hornady it might have “pushed” the bullet forward into the lands without a crimp. That’s it. With the Improved version, that’s not an issue as the load for the Hornady is not compressed, alleviating that concern.

The former Ruger and my current Ruger, before it was modified, would both sail the 500-grain Hornady along at just over 2000 fps from the muzzle at sane pressures. Plus, my son’s Ruger #3 in .45-70 would do the same with the same load. Now, before you get too excited and blow the proverbial gasket, let me quickly add that the load that gave a corrected MV of 2015 fps from the 500-grain Hornady from 3 rifles was tested for me by a reputable powder company in the States that gave a “thumbs-up”! The details are in my manual.

So, “rock yer socks”, no one has published this except yours truly! And, before I get a lot of irritating comments, let’s just say that I know what Hornady and others have published. BUT, if you have LYMAN’s Manual, check out the info on the Ruger No.1 and the 500 Hornady. AND THE CUP FOR A PARTICULAR LOAD that goes almost 1900 fps at a very modest 39,000 cup! The Ruger is MUCH, MUCH stronger than that!

But a 500-grain at 2000 fps+ is not only stepping on the heels of the .458WM, but getting into it’s very shoes, if we are talking traditional factory ammo. When we get to the .458WM, we’ll see it too is much better than the factories have given it credit for, when HANDLOADED! 

Back to the Ruger No.1 .45-70 Improved: As pictured, it weighs 7.4 lbs. Because of the long throat, allowing bullets to be seated within one-tenth to one-eighth of an inch of the .458WM, and because the .458 case is heavier in the web area than the .45-70 case, there is practically no difference in powder volume between the two cartridges when each is loaded with the 500-grain Hornady (for example). Add to this the fact that the .458WM has a veeery long throat, the .45-70 Improved can actually exceed the MV of the .458 with a 22″ barrel, when each is loaded with their best loads! Think that through, and you’ll see why… Internally, the barrel of the .45-70 Improved is longer by about 3/4″!

So, my Ruger No.1 in .45-70 Improved is in effect a .458WM… but the cases say it’s a ”.45-70″! It’ll fire the 500-grain Hornady at 2200 fps using enough H335, that’s not compressed!

How would you like to shoot that??? It generates 83 ft-lbs of recoil! And, I’ve fired those loads dozens of times. Probably hundreds, as I’ve gone through a few boxes of 500’s.

While I’ve shot a black bear with that load, it’s not my current favorite load for North America. That load would be more suited to African DG. Yeah, I know the Hornady Interlock is not a REAL DG bullet, but I do have a box of their steel-jacketed “solids” in my reloading cabinet just in case a bull elephant gets lost and wanders through our potato patch!

My REAL hunting load for these parts is the 350-grain Barnes TSX at somewhere between 2400 to 2500 fps. I haven’t settled on the load yet, but 66 grains of H4198 gives about 2470 fps, and that’s not max, but consistent. Hmmm… now let’s see… that’s 4740 ft-lbs at the muzzle. Do ya think that’ll take care of moose and bear without too much worry? The recoil of that load is about 53 ft-lbs… Quite a bit less than 83 ft-lbs, don’t ya think? About 2/3’s as much (64%). I think I can handle it… I think!

All for now… it’s late and I need to go to bed… but will be back in a few days to follow up on this theme.

Shalom

Bob Mitchell


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