Gascheck seating "jig" for Lee sizer
Piece of nylon with deep, medium and shallow holes drilled the boolits diameter
https://i.imgur.com/GnEgTWN.jpg
tape penny to bottom of jig under the deep hole to span hole in sizing die
https://i.imgur.com/FOHvzD1.jpg?2
Place boolit in deepest hole and set GasCheck on boolit
https://i.imgur.com/LTo75EQ.jpg
set jig in press and press GasCheck on to boolit
https://i.imgur.com/VRwx635.jpg?2
place base of GasChecked boolit in sizing die (still in the jig) and seat a deep as possible
https://i.imgur.com/KYfYfOJ.jpghttps://i.imgur.com/vhRpRpb.jpg
switch to medium hole in jig and seat
https://i.imgur.com/ZHsHZAM.jpghttps://i.imgur.com/vhRpRpb.jpg
switch to shallowest hole and seat
https://i.imgur.com/85Emh3Q.jpghttps://i.imgur.com/84G6iWP.jpg