Quote Originally Posted by Rhino0427 View Post
I realize I'm something of a new guy, but I need help from someone who has some experience. It says to adjust them using calipers (I have some), but I don't really understand that process and I don't want to jack up a bunch of 223 brass playing "trial and error". I read somewhere that it comes from the factory set at 1.75, but I'm more of a "trust but verify" guy. I'd like to know exactly how its set before I start grinding.

Any thoughts from the experts on how to get my measurement setting so I can get to work?
Easiest way is if you have an existing empty case that you KNOW is the correct dimension. The trimmer 'rides' up and down the drill bit that does the trimming and is held in place by two hex screws. Loosen those hex screws so that the trimmer 'floats' freely on the bit - then put the empty case that is known to be the right length into the trimmer and make sure the trimmer fits up against the case shoulder. This particular trimmer indexes off the case shoulder, so you need to be sure when the case is fully inserted into the trimmer, the trimmer is pushed up to contact the shoulder. Then tighten those hex screws. It sounds more difficult than it is.

Let me know if this was not clear and I'll try to clean up the description a bit.