gkh0825
gkh0825
3 posts
Joined May 2015

RT1200 trimming poorly

I have been using this trimmer for over a year on .223 brass without any problems. I am now working with .308 brass and the trimmer is not trimming vey well. It is compressing the brass into a large lip around the neck opening. With .223 there was a small lip easily removed with three twists of a hand help deburring tool. A .308 requires about 5 minutes per case using the same tool. I have set the die several times and adjusted the trim amount according to the instructions.  I have turned the cutter blade to use a new edge but it did not help. I installed my spare cutter blade, it did not help either. I have worked with Federal  and PMC .308 brass with the same results. Also, I noticed I am hardly getting any brass shavings like I get with .223 brass. I just stopped writing this and trimmed three cases. The performance is awful. The noise is also awful. With .223 I hear a zip sound and its done. With .308 it sounds like a dentist drill, and half the time it does not stop until I retract the case. The cutter blade just grinds on the neck opening with no effect, except to create the large brass lip. I have this trimmer mounted on a 550B which I bought in 1992. I have a lot of other Dillon equipment which has performed extremely well. Am I missing something about this trimmer? Is it not suitable for .308? I realize .308 is larger than .223 but that does not account for the results I am seeing. Any advice would be appreciated.
porkeypapa
porkeypapa
21 posts
Joined July 2012

RE: RT1200 trimming poorly

have you tried turning the cutter to a fresh cutting edge?
dillon
Administrator
dillon
3,222 posts
Joined July 2007

RE: RT1200 trimming poorly

It sounds like either the trimmer is turning backwards ( this is a DC motor, so this is possible) or else the cutter is attached backwards to the cutter holder.
gkh0825
gkh0825
3 posts
Joined May 2015

RE: RT1200 trimming poorly

The motor turns clockwise when viewed from the end with the power cord. The plug is made so that you can't plug it in backwards. Is the cutter blade marked to indicate which side faces away from the holder? Thanks for the response. 
dillon
Administrator
dillon
3,222 posts
Joined July 2007

RE: RT1200 trimming poorly

The cutter blade is not marked, but there is a slight bevel on the non-cutting side at each cutting surface.
gkh0825
gkh0825
3 posts
Joined May 2015

RE: RT1200 trimming poorly

Good news, the blade was on backwards. I had not noticed the beveled edge before. I removed the blade and stood it on one edge, forming a small triangle. This triangle 'leans' due to the bevel. Viewed from the side this triangle leans to the right. I inserted the mounting bolt from the left, re-mounted the blade, and trimmed some brass....Perfect. And, no touchup needed. I am going to finish these 308's and set up for more 223's. I bet  I won't be touching them up anymore. Thanks for the help!