458 3"

**FrankH** · 05-02-2009, 21:25

Recently a 458 win mag came into my possession, after a 3 month wait the licence was approved. I have a 416 Rigby, so have been thinking about reaming the 458 to 3 " Anybody have any experience or advice to offer?

Thanks

**makeminea10mm** · 06-02-2009, 00:20

When I saw the subject line of your post, I thought you were going to tell us about a 458 with a 3" barell.. confused0068

Sorry, I got no advise on that question, but what was your secret wrt getting the licence so quickly? confused0083 grn1

DS · 06-02-2009, 08:53

FRank, I recently read up on the 458 WinMag, 458 Lot (which I have) and 458-3" Belted Express.

A good source of info on this subject is "Big Bore Cartridge Load Data Collection" by Pierre van der Walt and available from Zimbi Books.

It seems on the 3" one will have to consider
1. possible less than 100% feeding with the long cartridge
2. working with duplex loads if one wants to really get the benefit of the long case. Slow burning powders for the 458 is recommended and this coupled with the long case is apparently a bit of a hiccup to be considered.
3. do not shoot too much? 458 and 458Lot ammo in the 3" because it could lead to throat erosion (same is applicable to the Lott with 458wm ammo).

**FrankH** · 08-02-2009, 21:41

Originally Posted by Khumba

FRank, I recently read up on the 458 WinMag, 458 Lot (which I have) and 458-3" Belted Express.

A good source of info on this subject is "Big Bore Cartridge Load Data Collection" by Pierre van der Walt and available from Zimbi Books.

It seems on the 3" one will have to consider
1. possible less than 100% feeding with the long cartridge
2. working with duplex loads if one wants to really get the benefit of the long case. Slow burning powders for the 458 is recommended and this coupled with the long case is apparently a bit of a hiccup to be considered.
3. do not shoot too much? 458 and 458Lot ammo in the 3" because it could lead to throat erosion (same is applicable to the Lott with 458wm ammo).

Thanks for the info.

**jasonb** · 19-02-2009, 14:55

by doing that you would in essence have two similar performing calibre's. try the big bore ass of south Africa, i think the man to speak to there would be Mauritz Coetzee.