In years past I did a lot of work on military actions. In the 70's it was still profitable to convert military actions into sporter rifles for hunting.
I was...and still am.... a fan of the '98 Mauser action. It had no equal among military actions of the day for conversion to sporter configuration. Even today I can think of no commercial or military action I prefer over the '98 Mauser.....including the highly praised Model 70 Winchester which is nothing more than a modified Mauser.
I was never a real fan of the '03 Springfield. It was a modified Mauser that was NOT an improvement. Compared to a '98 Mauser it was too heavy and asthetically inferior. Particularly the magazine cut-off and cocking knob added no value except weight and ruined the lines of a completed rifle. I didn't "hate" the Springfield...it is a very strong and useful action....but I could see no reason to chose the Springfield over a Mauser that was generally a bit cheaper and made a superior finished rifle.
The one exception to my preferred Mauser was the 1917 Enfield. True it was a modified Mauser that was overly heavy and ugly to boot. That broke-leg bolt, oversize sight ears and huge hole in the receiver were major problems that had to be overcome. The cock-on-closing feature was not as big a problem for me as it apparently is for others....but even that could be overcome.
What made the Enfield so valuable (to me) was the size of the action. Up to the .30-06 length cartridges, the Mauser was far more preferable to any other action. But once you moved up to the longer "true" magnum chamberings, the Mauser was just a bit too small.
True, you can modify a '98 Mauser to take .375 H&H length rounds, but this requires that the strength of the action is compromised. With powerful full-size rounds I am uncomfortable with ANYTHING that reduces the strength of the action.
There ARE magnum length Mauser actions out there, but they are uncommon and very expensive. The 1917 Enfield actions are easily available and inexpensive......and are long enough to chamber .375 length rounds without modification. The Enfield does require a bit more work than the Mauser to make it an attractive finished rifle (removal of the sight ears, plugging the "hole" in the receiver, removal of that hideous bolt handle and (if one desires) the conversion to cock-on-opening).....but you end up with a true magnum length action that has none of it's strength compromised. Even the main "flaw" with the Enfield action....it's excess weight...becomes an advantage in a heavy recoil magnum rifles.
Much as I love the Mauser actions and would prefer a magnum-length Mauser over an Enfield....there has never been a better military action for conversion to a magnum rifle.
