Author Topic: 458 win mag rechamber (Read 1211 times)

greyarea · « **on:** April 18, 2006, 08:36:40 PM »

I am thinking about rechambering a 45\70 barrel to 458 win mag or 458/2.0" does anyone see any major problems with this combo?

Uncle Ji · « **Reply #1 on:** April 18, 2006, 10:02:45 PM »

The main problem I see is ALOT of PAIN when you pull the trigger. A 7lb. Handi is sore enough with stout 45/70 handloads, in 458 Win mag that adds a whole new meaning to the word "pain". Now the 458/2.0 is very similar in power to the 450 Marlin which again equals stout reloads and Buffalo Bore and Garrett 45/70 loads so is doable but you'll feel it though not as bad as the 458 Win Mag. H&R did make 450 Marlin Handis, wonder if any barrels left?

greyarea · « **Reply #2 on:** April 18, 2006, 10:08:25 PM »

The biggest reason i did not want to get the 450 marlin is brass price @ $56.00 per 100, the others can be formed from the 2500 300 win mag i have on hand. Also i have 6 lb of lead in the stock already and will tune that amount to the load of the finished gun.

Haywire Haywood · « **Reply #3 on:** April 18, 2006, 10:50:34 PM »

The frame is not strong enough for magnum calibers. Your Handi will be ruined in very short order.

Ian

nomosendero · « **Reply #4 on:** April 19, 2006, 02:50:08 AM »

That would be a big no for the .458 Mag.

Concerning the .458 American, this is pretty much the same performance
as a 450 Marlin & those barrels are cheap according to the web site. Concernig the cost of the brass, a 100 will go a long way with this type of case. Why not sell some of the 300WM brass & then buy the 450 brass.
Also, surely the rechamber job to 458American would cost something &
your time to form cases would be worth something too, I would think.

Mac11700 · « **Reply #5 on:** April 19, 2006, 04:57:01 AM »

Quote

Although the 450's web/rim design appears to be that of the 458 Win Mag (or its parent, the 375 H&H), in fact it is a new design by the Hornady team. Two design goals for the 450 were: that it would not chamber in a 45-70, nor a chamber of another 375 H&H belted magnum derived cartridge. Any belt design would have precluded the chambering in a 45-70; but by adding an extra wide belt, the 450 also precludes the chambering in a 7mm, 300, 338 Win Mag. As such, although others regard the 450 as a commercialized 458x2" American (by Frank Barnes), this author would rather describe the 450 as a new cartridge, designed by Mittelstaedt et al.

I

One easy way to tell if it would work...Look at the top end loads for the 450 Marlin...and then look at the start loads for the 458 Win Mag..you'll see their not even close and you need to find several that overlap ...I'm sure you will be able to find a couple of down loaded loads that will be simalar..but..I really don't think the frame will last real long with full house 458 Mags being shot thru it..and that's the whole purpose of the conversion isn't it..

Have a Great 1

Mac