Originally Posted by killen
Could this not indicate that JSP have a range of dies for each head size. So Die 42 for 4.51 is not the same as die 42 for 4.52?
Not sure but probably not.
There is a lot of variation in head size in one tin of 500 pellets (see airgunaccuracy link posted above). In my opinion the head size on the tin is a useless figure.