For those who doubt the strength of the No. 4...

[Blastattack]

It's bloody strong. Watch the video.

The .300 Win. Mag. develops ~23% more pressure (avg. maximum of ~63kPsi) than the .303 British (avg. maximum of ~51kPsi), but the increased size of the Win. Mag. develops 46% more bolt thrust than the .303. Despite this, the rifle readily fired and extracted 10 normal rounds, and 5 "redneck proof" rounds (oiled cartridge, which reduces friction effects, and apparently doubles bolt thrust) before failing. and the kicker? The left lug was already partially cracked through decades ago and survived numerous previous military and commercial proofings, as well as many (likely thousands of rounds) of both .303 and .308/7.62x51. That is incredibly impressive. And its failure was 100% safe to the operator. Remarkable indeed.

 

[bearhunter]

Now that was interesting. Thanx for posting

 

[Evanguy]

Its not the strength people question, its the springyness of the rear locking action they speak of then others read that and assume the action is weak by not knowing what they meant

 

[Eaglelord17]

People do doubt the strength but that is in comparison to something like a M98 Mauser or 1903 Springfield which can handle significantly more pressure reliably. For 7.62 NATO and .303 British it is a perfectly sufficient action and the argument can easily be made that the Mauser and Springfield actions are overbuilt for what they need to handle.

No.1 Mk 3 actions are much more of a gamble and are significantly weaker than the No 4 action, not really being able to handle 7.62 NATO. This whole debate actually comes out of the post-war sporterizing era when people were converting these actions into magnum hunting rifles. If used as intended there isn’t really much issue for basically every service rifle.