Don't know if this answers your question, but I would avoid adapting an adapter. That is to say, I would use a max of 1 adapter. The more you use, the more your tolerance level goes up, and could lead to problems like not having the can concentric to the bore which = baffle strikes. A good machinist/smith can either thread or attach an adapter that will be concentric (with can mounted) to the bore. This would probably cost a bit more in money and time to have done, but if you are going to drop some dough on a can, it would be worthwhile to do this.
Generally, I have found that most decent factory barrels will take a standard can mount and keep it reasonably concentric, provided it is indexed evenly. Adding an adapter throws another factor into the equation. It can be done, but it should be checked with adapter - mount - and can attached. I would do this for each weapon that uses an adapter to fit the mount/can.
ETA: You could just use the ole' cleaning rod trick. It gives you a rough idea of concentricity. It is by no means a true check, but can alert you to possible alignment problems to have looked at.
Generally, I have found that most decent factory barrels will take a standard can mount and keep it reasonably concentric, provided it is indexed evenly. Adding an adapter throws another factor into the equation. It can be done, but it should be checked with adapter - mount - and can attached. I would do this for each weapon that uses an adapter to fit the mount/can.
ETA: You could just use the ole' cleaning rod trick. It gives you a rough idea of concentricity. It is by no means a true check, but can alert you to possible alignment problems to have looked at.
