How weapons today compare to the guns of the wild west.
On the whole, both the Wild West guns and today's service-caliber guns are pretty equally effective in most respects, I think, as their intended uses are more or less the same. Today's guns are more efficient in some ways, such as barrel length, weight, capacity in some cases (often using smaller cartridges because of smokeless powder), and rate of fire, but these things vary by the individual case and should be obvious enough.
Also, for self-defense use today's JHP bullets are thought to offer increased effectiveness, all else being equal, but you have to decide for yourself how much (and the solid and often quite hard lead bullets they used back then have their own advantages).
Would the 357mag be a superior handgun against the 44 or 45 colts of that time.
Not necessarily more than it is superior to today's .45 ACP handguns, if it is at all. It depends on usage, as there are certainly some .357 Magnum loads that are more effective against larger creatures, but against humans, that's a whole other discussion. In terms of raw energy, it is certainly superior, that's true.
How about our pistol calibers. 40acp or 45acp. how would they stand up to the revolvers then.....
They would have more or less the same ballistic performance if they all used the same type of bullet. As 9mmepiphany pointed out, .38-40 WCF was the close equivalent of today's .40 S&W, although it's bottlenecked like .357 SIG, and the same pretty much goes for .45 Colt and .45 ACP.
Note that I've been referring to the later, more familiar Wild West era. Earlier cap & ball revolvers were generally less powerful, closer in performance to smaller modern calibers such as .38 Special, .380 ACP, or even smaller. The bullets used--sometimes literally lead balls--were also less effective than today's bullets, but they were still lethal.
what i always found interesting was that until the introduction of the .357Mag, the most powerful handgun round was the muzzle loading blackpowder .44 Walker
It depended on how you loaded it, I suppose, but if you wanted your Walker to last a fair amount of time, then you'd probably be hard-pressed to load it hotter, in terms of external ballistics, than .45 Colt.
1870s Black Powder Loadings for .45 Long Colt were 250 + or - grain Bullet and + or - around 1000 fps...probably 7-1/2 inch Barrel.
With a full 40 grains of black powder, you might be able to get 1000 fps with that Cavalry barrel length on a Single Action Army, but most people used shorter barrel lengths such as 4¾" (Gunfighter) or 5½" (Artillery), which of course reduced velocity somewhat. It was also common to use lighter charges of black powder, such as 35 grains.
.45 ACP was and remains the ballistic equivelent of the Black Powder .44 Russian Cartridge, not .45 Lomg Colt.
It's a bit hotter than .44 Russian. Let's just say that .45 ACP is somewhere between .44 Russian and .45 Colt, although to be fair, most factory .45 Colt loads weren't as hot as the one you described (which was a physically maxed-out load) and .45 ACP (and .40 S&W for that matter, albeit with smaller, faster bullets) can potentially be loaded very nearly as hot as the hottest .45 Colt black powder load (modern smokeless .45 Colt loads designed specifically for stronger revolvers than the SAA are a different story altogether).
1898-1899 Loadings of .38 Special when Standard Loadings were in BP, were 158 Grn Bullet, 950 fps...6 inch Barrel.
Ironically, despite the far superior energy density of smokeless powder, black powder loads in certain calibers could often be hotter because of how they burn and the pressure curve that results, albeit with a much larger charge of black powder. .45 Colt appears to have the same issue with standard pressure loads, unless it is very carefully loaded.
Most muskets weren't loaded with more than 60 grains of BP, which in a musket isn't quite going to match decent .44 Magnum loads, or ironically modern smokeless .45 Colt+P loads, for that matter. Many lever-action rifles shot pistol cartridges, such as .44-40 WCF, as well, and they can't match a .44 Magnum revolver, either. Obviously there were very large rifle calibers back then, such as the .45-70 Government, but even then the modern .500 S&W Magnum can match or even exceed its performance in a revolver.
