Brass frames and 777
Let's be a little careful here. ANY BP pistol, brass or steel frame, overloaded with 777, Pyrodex, Goex, Swiss, etc. is dangerous, just as a regular centerfire cartridge that's been overloaded is dangerous. One must always take care to not overload your weapon.
I have both brass and steel framed BP revolvers, and have shot many, many rounds through them with both 777 and authentic black powder. None have ever blown up, which I attribute to care in loading and cleaning.
The statement, "...if you were to load one of these brass framed guns with Tripple 7, you could be in trouble and need medical care." is overstating the issue considerably. Brass framed replica revolvers do not blow up or cause the need for "medical care" UNLESS they are abused, which is certainly the case for any firearm. They are not inherently dangerous whether loaded with real or any of the substitute black powders, including 777.
I understand and agree that brass frame revolvers can wear out or become loose quicker and more predictably than steel frame revolvers when subjected to repeated overloading, and at some point they can become dangerous, but I strongly disagree with the statement quoted above. That simply is not my experience in 35 years of shooting black powder.