Thread identification

[csmiffy]

It could quite possibly be 9/16x24 but your can and barrel threads are different sizes, It is quite common to turn a thread until the part threading on just "fits" and threads on nice without looseness, which could mean your barrel thread tho the same pitch and "size" still wont fit.

Regardless without an accurate measurement of thread pitch as per above posts we are all just guessing at this point.

I agree but you would think that the suppressor is done with a standard tap or setting on the cnc.
Then its only the barrel that needs fitting but I spose if the suppressor is machined on a lathe there is always the chance they are different from batch to batch.