Howdy
Ruger has managed to make something that was unclear even more confusing.
The "original model"* Vaquero, manufactured from 1993 until 2005, was built on the same frame as the Blackhawk. The cylinder was roughly 10% larger in diameter than a Colt, which resulted in more steel surrounding each chamber. The larger cylinder was housed in the larger frame.
This photo shows a Stainless "original model" Vaquero cylinder with a Colt Single Action Army cylinder on the right and an Uberti Cattleman cylinder on the left. All three cylinders are chambered for 45 Colt. One can plainly see how much more metal surrounds the chambers in the Ruger than the other two revolvers.
In 2005 Ruger ceased making the "original model" Vaquero and replaced it with the New Vaquero. This model was similar in size to a Colt, with similar thin cylinder walls when chambered for 45 Colt. Sorry, I don't have a 45 caliber New Vaquero to show for comparison.
Ruger has since made things more confusing by dropping the name New Vaquero, and is now calling them all just plain Vaqueros, even though all present production is of the smaller size.
To answer your question completely, one would need to know which version of the Bisley Vaquero you are talking about. Recent production or earlier than 2005?
Regardless of what some shooters try, Ruger was very specific when the New Vaquero was introduced in 2005 that only SAAMI Max spec loads should be fired in it, nothing more powerful.
* the words "original model" are my own. There is no official Ruger designation for the larger model Vaquero, I simply put the words original model in quotes to make it clear which model I am talking about.