RCBS Trim Pro problems

[rd2play]

I wasted about 20 cases of 308 Win trying to adjust/set my new RCBS Trim Pro with a 3 way cutter, and I'm still not getting anywhere. In theory it's extremely simple, but for some reason I get all sorts of different lengths.

I trimmed one case to 2.008, then I tried a few others, then I put the 2.008 back in, without adjusting the trimmer. Second time it cut it to 2.003. Huh?? Same case, same adjustment, and the second time it trims it even more? And then it trims other cases only to 2.011...

At some point something out of the cutter got stuck in a case. Something long, maybe the chamfer component. I was able to push it back in, and it stayed there.

Obviously there is something wrong in there, but I just can't figure it out. There aren't that many moving parts. It's been a frustrating couple of hours. Does anyone have any ideas?

[Whiterabbit]

case resistance will let you chuck the trimmed case in there and trim even more.

I suggest you inspect the trimpro housing for play or flex. Mine's not perfect and flexes pretty readily. I also can tolerate some variance in case length without issues.

What kind of tolerance do you expect with your cases? .0001"? You can't pick "well, not .009!!" as your tolerace.

[rd2play]

I think I figured it out... Usually those 3 way cutters are good to go out of the box, but this one needed several adjustments. By the time I figured it out I had stripped a tiny allen screw, so I just ordered a new one.