I wouldn't call Krieghoff's published standards "optimistic", it's just that all of the .500/.416 rifles I've seen have had shorter than "standard" barrels. Most are 23.5" rather than 25.5". Some of the velocity claims I've seen on the net from handloaders are definitely optimistic.

I chronographed several batches of .500/.416 factory ammo from Krieghoff (Romey) in a new Krieghoff Classic with 23.5" barrels five years ago. As you would expect with barrels 2" under standard, none of it came up to 2300 fps. IIRC, it averaged in the 2270 fps range. Factory ammo is loaded with blended (multiple propellants), non-cannister grade propellants in order to get 2330 fps from a 25.5" barrel and keep pressures under 45,000 psi. I doubt that handloaders, using cannister grade propellants, can exceed standard velocity without exceeding max pressure. Some claim 2400 fps from 23.5" barrels!

Nuts.

I've owned both .400s and have been shooting the 3" for almost 20 years now. In one session, I fired 25 rounds from the .500/.416, a dozen or so from the .400 Jeffery, plus a few rounds of .400/.360, all from the bench. I'm relatively insensitive to recoil - up to a point. The .500/.416 might kick a tad harder than my .400 but, to me, it's hard to tell. I enjoy shooting both, even from the bench. I've also done a fair bit of load development with the .470 and have shot several of them from the bench. To me, the difference in felt recoil between the .470 and the .400 Jeffery/.500/.416 is biblical. A 35 to 40 round range session with the .470, all from the bench, would be beyond my endurance.

Incidentally, accuracy of the Krieghoff with the Romey factory ammo was marginally acceptable for hunting purposes at 50 yards, and useless at 100. The ammo was erratic. With handloads, accuracy at 100 is superb. I've fired the Romey stuff in several other rifles in different calibers with similar results.
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