[Jeff Higgins]

Bill, the .338 Lapua is a somewhat specialized round, with an awful lot of hype surrounding it. It actually provides no discernible advantage over any other high capacity .33 caliber. The .340/.378 Weatherby is pretty near its ballistic twin, as is whatever Remington calls their .33 caliber "ultra mag". The problem with the Lapua round (and the Weatherby), and what sets them apart from other "magnum" rounds, is that they require a special size bolt face, larger than "standard" magnum rounds.

So, it's really not that the M70 is not "strong enough", it's more that it has not been made with that particular bolt face diameter. The rifles that have been made to accept these rounds also feature a larger receiver ring to accommodate that larger bolt face. The original "magnum Mauser" on which the .416 Rigby was built, along with the Mark V Weatherby and P17 Enfield are large enough in diameter. The M70 really isn't. It can certainly have the bolt face opened up to accept this larger rim diameter, however, it does reduce the amount of "meat" around the case head area. It really would be better to use an action originally designed to accept these larger case diameters.

That said, there is nothing a .338 Lapua can do in the field that a .338 Winchester Magnum or .340 Weatherby can't. The Winchester is at about the ideal for case capacity vs. bullet weight and "combustion chamber" (bore volume - barrel length and bore dia) size with available powders. That, and it's about at our tolerance level for blast and recoil in a reasonably sized rifle. Myself, I would pass on a M70 based .338 Lapua for all of these reasons. If you really need a big thumpin' .33 (and most of us really don't) just look for a M70 in .338 mag.