Judson:
My own experience is almost entirely with British doubles, which are generally made at the 'correct' weight for calibre. I have never even seen a Searcy in the flesh, and probably only a dozen or so Merkels, Kreighoffs, Chapuis, etc.

Against that background, almost all Brit nitro doubles are pleasant to shoot as the gun-weight generally increases with power level. That said, 10 to 11 pound guns are OK to carry all day, and if well-stocked and balanced are quick to get into action and lively to shoot. On the other hand, 12 to 13 pound rifles are definitely pushing the envelope, becoming too heavy to carry all day and unhandy to mount and shoot quickly.

Rifles chambered for the .450 to .475 family of cartridges can be made to fit well into the former category, ie 10 to 11 pounds, whereas the .500 is a definite step up in power IMHO and really needs an extra pound or two of gun weight to shoot comfortably.

I am well aware of the current trend to build light-weight .500 doubles (...on 20-bore shotgun frames, we keep hearing?

) and in today's world of "point it where the PH says and fire one good shot" then who cares how light the rifle is, or how hard you get belted. But those of us who hunt regularly on foot and fire many shots at game with our doubles in an average day will need a comfortable rifle to carry and shoot.

A simple deduction from all this is that the .450 to .475 NEs are a practical maximum for a 'working' double, and that the .500 is a different animal altogether which is probably at its best on guided pachyderms and quite simply too much weight and power for enjoyable everyday shooting.

Just my own opinion gentlemen, flame away if it makes you feel better!