Most has been covered above already but in simple terms the New model is slightly narrower, more resembling the profile of the SAA. Smaller grip and where its really differs is in the length of the cylinder. The Old model is slightly longer and able to take the 300g+ bullets whereas you may find that the New model will not handle the heavier bullets without hanging out the end of the cylinder. In reality the New Model is really an answer to the demands of the Cowboy action shooters. Both models are excellent, but you need to decide what you are going to do with it. In Canada, we really dont need the big heavy bullets, as the paper really doesnt notice the difference.
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