Originally Posted by Abnmp78
Will t8/9 mags work in a t9 with the fs conv?
Yes. The modification is only needed for the T8.1 and T9.1 because the .1s use a thicker outer diameter barrel. T8s and T9s with the FS kit use a barrel with the same outer diameter as the original barrels.
FYI: The size change was due to a new style of ball detent in the .1s