One thing to remember is that most corporate lawyers have a very large stick crammed up their derrieres, and their first thought is towards covering the corporate butt from any conceivable possibility of litigation, especially where consumer combustibles are concerned. The thought of having John Q Public stuffing an explosive compound into their client's product, no matter how much it's been tested or proofed, sends them into spasms. So if a gun is proofed to use 30 grains safely, the lawyers are going to say "no more than 15-20 grains" in order to stay within their conceived limit of liability. Their thought is, "hey, you want to use more, than it's your business; if anything happens, it's no skin off our nose... but don't say we didn't warn you!"
The charges for these guns were developed by the original manufacturers to be safe and practical in light of the properties of black powder, and the metallurgical and manufacturing capabilities at the time of the initial designs (most during the early-to-mid 1800s). The steel being used for the manufacture of these guns today is so far superior to that available to the original makers that it ain't even funny. And todays CNC and CAM systems are beyond anything Sam Colt and Eliphalet Remington could have conceived of even in their wildest flights of fantasy. Take a good look at your Italian made repro. All of those proof stamps aren't added just to booger up the looks of the gun (although they accomplish that effect admirably). They mean the guns have been tested to be safe for use by the public for the purpose for which they were designed (making smoke, noise and punishing threatening sheets of paper and rampaging plastic milk jugs). And that means using the charges the guns were designed for.
You want to stuff 45 grains in your Remmie? If you can still cram a ball in on top of it, then, by all means, go for it. You want to put 60 grains in your Walker? It didn't work too well in the originals (though there is some evidence that the cylinders burst due to the conical bullets being loaded backwards by the troops; and certainly the rush job by Whitney's work force didn't help), but today's modern guns can handle it and not even break into a sweat. Charges for brass-framed guns should be kept light due to the nature of the material, but steel-framed guns can handle full charges with no problems.
When you think about lawyers, just remember; the purpose of their jobs is to be anal-retentive. I ought to know, 'cause I married one. But that's another story.
