450 LM "LeGendre Magnum"

[B swift]

Thought that seemed like a long lead off base. I'd love to turn my Sig 716 into a real THUMPER!

[wildcatter]

Just got a report from Gunny, he was at his Father's, under deplorable weather conditions. He didn't get to shoot until this morning and then very little.

The Gunny Reports that he has seen 2550fps, using 325gr Barnes Busters, and this is basically a starting load, meaning he was not at Magnum Pressures yet. If I had to guess, he'll see speeds in excess of 2650fps or better, before he hits a Max loading.

There was no time to shoot his resized 350gr Interlocks.

Conclusion: Somebody look it up, but I think at 2550fps, w/325gr bullets, he may still be in the 458 WM performance envelop, and the numbers with the 458 will be with 24-26" Barrels, Gunny's barrel is 20" long.

He is using 1680, but with those heavier bullets, he may have to go to 4198??

..t

[Texas Sheepdawg]

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[pitted bore]

As requested, here are some 458WM numbers for comparison:

Hodgdon shows a 300-gr Barnes TSX at about 2800 fps (2793) with H4198. Kinetic energy=5195 ft-lbs.
(Hodgdon on-line data: link to Hodgdon data center)

Similarly, Lyman's Handbook #48 shows a 300-gr Sierra with N130 at 2789 fps, about the same speed.

With the 350-gr Speer soft point with H322 powder, Hodgdon shows 2589fps with an 80-grain compressed load. Kinetic energy=5208 ft-lbs. With exactly the same components, Lyman shows 2550 fps.

Hodgdon doesn't supply test barrel lengths. For the light-bullet loads above, Lyman used a 24" test barrel.

The 458 WM loads are almost all compressed. Most of the loads published are probably 10-15 years old, so there may exist powders now that are a smidgen faster than RL7 and IMR4198 or H4198. These powders might allow the 458 WM to go a bit faster with the lighter bullets.

--Bob

[wildcatter]

Very Good guys, I think we have much more to see, but things are looking very well indeed.

I just did a quick load on the 458wm using a 325gr FTX and a 100% fill capacity w/no compression. The pressures are way far too high with 74.85 gr of H4198 (63,784psi) and from 24 inch barrel yields 2714fps.

So, without knowing the final results, I think the 20"-LM is prolly going to be quite competitive with to old elephant gun, what-do-you-think? But the elephant gun using a factory loading, the LM may just equal (+-) the old work horse. For sure the Factories, loading the 458, would never compress those loads and they'd stay in the 51,000psi area..

..t

[gunnut]

Not a whole lot of fun today. but, off to a good start loading at the range! 325gr Barnes Busters over 62grns. of 1680 yielded 2550fps! Mild load with case sooting before my scales died. Hands and fingers cold,..Good reason to go home!

[commander faschisto]

Kawabunga! 2550 with 325gr buster, is a "mild" load?? This should be interesting!

[B swift]

Uhh Huh~!

[gunnut]

My dummy cartridge will hold 65grns. of 1680 with the 325 Barns Busters seated to a C.O.A.L. of 2.8. not a compressed load. At 62grns. and 2550FPS The Federal 215 Primers look good. Some sooting around the case mouth and down the side. Time to work up to the max load!

[wildcatter]

And I am waiting with baited breath, for those numbers. Gunny is out shooting today and I expect a call anytime now..

..t