9mm issues

[wild_weasel]

If your RCBS 9mm Dies came with the wrong seating stem give RCBS a call. They have great customer service and if you have the wrong stem they will most likely send you the correct one free of charge.

[jdmstuff]

Have you tried flipping the stem over? They're usually double ended and one side is flat while the other is for round bullets.

[Bt Doctur]

The stem really shouldnt make that much of a difference.
" If I back out the die then the COAL is too long"
You set the die to only do the crimping operation.Bullet depth prior to the crimping stage is determined by the stem setting.
Take a empty case, loosen the crimping die a few turns, run the case up and adjust die untill you feel a slight resistance, temporarily lock die, insert a bullet and run the case into the die and adjust stem to just shy of the desired depth.Now turn the die in a 1/2 turn . Test a bullet for correct depth and crimp.

[bitethebullet]

TMJ...Truncated metal jacket..That would indicate its a stem similar to a wad-cutter...the combination of TMJ and long 147gr probably isn't a good combination... like said previously, it should be seating from the give not the tip....