The original Vaquero large frame could handle "Tier 3 Ruger Only Loads" at ~30-32,000psi, which is generally considered a 280-300grn pill around 1200fps. The Mid-Frame New Vaquero is NOT designed to tolerate the Tier 3 loads, but can handle "Tier 2 Ruger Only Loads" at ~20-23,000psi, which is generally considered a 280-300grn pill around 1000fps.
The original Vaquero was the same frame as the Super Blackhawk/Blackhawk, so it could handle anything you could throw at any 45colt revolver. The New Vaquero is a mid-frame, and again, it can't go QUITE as hefty as the large frame could, but it's still a quite virile revolver!
While the Tier 3 loads are surprisingly formidable, the Tier 2 loads are no slouch in their own right. 300grn at 1000fps is a heavy hitter, and I wouldn't hesitate for a second to deliver it after a large bear. In that particular situation, I'm not necessarily convinced that ~200fps is going to make a huge difference in killing performance.
As far as the other differences, I responded this at the OTHER RF a while back, so I copy and pasted it here. It's a listing of all of the differences between New and Old, but was written in the context of cowboy action shooting, so many of these 'upgrades' and differences are more useful in that sport, even though I personally value most of these upgrades in any revolver, whether it's a CAS gun, belt gun, hunting gun, or bear gun...
Differences in New and Old Vaqueros, with prices to make an Original Vaq more like a New Vaq:
Functional Differences:
Free-Spin Pawl: Ruger started putting these into New Vaqueros themselves, rather than making us all buy them aftermarket from Power Custom. This saves you $45. We could always alter the original pawl's for free, or buy factory pawls for $5 and alter the new one.
Indexing Pawl System: Ruger implemented this for all New Vaqs. Old Vaq chambers didn't line up with the loading gate, New Vaq's do. We used to pay Power Custom for half-cock hammers to make that happen, now we don't have to. Many shooters disable the Indexing Pawl (or remove it) to give themselves a free-spinning cylinder. If you want the loading alignment, this saves you $150-200. You CAN buy the New Vaquero parts, then drill, bottom, and tap an Old Vaq for the New Vaq plunger, total cost around $30 if I recall correctly.
Hammer: New Vaqs actually have a higher, longer "long horn" hammer. No idea why they did this, as it was seen as a downgrade by most CAS/SASS shooters. $30 to replace the New Vaq hammer, the same price we all paid to replace our old Vaquero hammers with SBH or Bisley hammers.
Overall Frame Size: The New Vaqueros are smaller and lighter. The original Vaqs were a large frame, the New Vaq's are a medium frame, similarly sized to Colt SAA's. For fast shooters, this means they are faster handling. For others, it means they recoil more. SASS/CAS loads are never heavy recoiling, so the handling speed is a benefit. There was no way to make an Old Vaq this light, so there's no monetary difference, just a speed advantage.
Now for a few of the "less functionally important" differences between Old and New Vaqs:
Crescent Shaped Ejector Rod Button: It's a little easier to grab to unload, but the big benefit is that it LOOKS way better. I think these run $7 to have Ruger send you a New Vaq crescent ejector that will fit fine in an original Vaq.
Beveled Cylinder noses: Doesn't really make reholstering faster unless you have a poorly crafted rig, but it IS aesthetically pleasing. Many of us did it to our old Vaq's, to the tune of carefully applied elbow grease, or $50-150 at the smith - blued cylinders would obviously be at that higher price since they'd need reblued.
Grip Frame & Grips: The Old Vaq's were the larger XR3-RED, the New Vaqs XR3 grip frames are slightly smaller, with a steeper/taller grip angle. Your knuckles are slightly closer to the trigger guard. The Old Vaq grips were "fat bottom girls" so they felt like you were choking the grip frame. The New Vaq grips are more parallel sided, which feel too small in my large hands. Colt SAA grips will fit the New Vaq if you simply fill and redrill the locator pin holes, they would NOT fit the larger XR3-RED Old Vaq grip frames.
