I can not speak for the new Ruger Bisley Vaquero for grip size, but I have laying in front me right now a Ruger Vaquero and a original Colt Bisley. For sure the Colt Bisley has a bigger grip than the Ruger Vaquero. Other than the Bisley bigger grip the differance is when you bring the Bisley up to fire it you have to come up higher or give your wrist a upward twist to get the barrel in line with a target. If you were to hold the Bisley with your hand in the same position as you hold the Vaquero you would be shooting 2 to 3 feet low at 25 yards. In looking at a picture of the Ruger Bisley the grip does not look like it has the same shape as the Colt Bisley.