Hey folks, I have a problem and am hoping we can resolve it here!! I do some reloading and am having a problem with my case trimmer, or something. Some cases come out short with out me changing my micrometer settings, and I don't see why!!! This is RCBS equipment, manually operated with micrometer settings. Any advise will be greatly appreciated!!! I have not had this problem before and have no idea what is causing it!!!

Vint, how much shorter?

I'm also using an RCBS Trim Pro case trimmer. shop.rcbs.com/WebConne...13J036N012

I had the old style with a collet and had a lot of trouble being consistent. With this newer style I have seen some difference in length, maybe 0.001-0.002" or so, when I push harder on the cutter while turning it.

Mine is only 1 year old. It is a replcement for the one I lost in a fire. I am trimming 270 cases to 2.53 and get down to 2.52 or less once in awhile. I will have to go back and recheck to be absolutely sure!Are you saying I need a new collet? It strikes me as really wierd since it does not happen on all cases.

I’ve got a Lyman trimmer that is notorious for going .005-.008 short!!!
I also have a Forster that will occasionally cut one a little shorter.

One of these days I’m going to by a Wilson case trimmer.
In one of their adds they reference the fact that collet trimmers will cause varying lengths.

Pumpkinslinger wrote:

I had the old style with a collet and had a lot of trouble being consistent. With this newer style I have seen some difference in length, maybe 0.001-0.002" or so, when I push harder on the cutter while turning it.

I think Pumpkin has highlighted one of the problems. Most trimmers can be sensitive to how much force is used on the cutter and can cause some springing of the shaft. Collet style holders can also be a little less than accurate depending on how tight you turn the locking mechanism for each case. It's hard to be perfectly consistent case to case. My Lyman can vary depending on how tight I set the holder for each case.

OK, I can relate to pressure,etc. What I am hearing is that I need to be more consistent and I can certainly relate to that as it is a huge part of reloading and shooting!!! It strikes me that if a case is "tipped" in the holder it will be short, but how do we check to see that it is "square"? Would a "bubble level" work? Another question is How will this short brass affect performance if it is reloaded, or is it throw away brass at that point???

Unless your doing the benchrest thing I wouldn’t worry about it Vint.
You’re not going to see it with the typical hunting or varmint rig.

The short ones will grow back. If it bothers you load them and use for fouling shots.

I've got the RCBS Case Trimmer 2 (with three collets) and with practice of over 20 years with it, can keep cases to within +/- .001. But if I forget and apply too much pressure it can really shorten a case or not trim it enough if I use too light of a pressure...

Vint...Practice, practice, practice. Oh...Wait...That's for shooting...

I reloaded with a Lyman 310 before this and never trimmed,so it is a new experience and I do believe you are right in exhorting me to practice, practice, practice!!! As they say practice makes perfect!!!! I want all bullets to go into one hole you know!!!!

You never trimmed cases ??? What am I missing here ???

That was 40 years ago and lay offs were common so some things went by the wayside. Never had the chance to shoot and reload that much, so 40 years later I am still a neophyte reloader!!!

Vint, is yours the collet type or the shellholder type that I posted a link to?

Mine is the collet type with micrometer adjustment.

The old collet type was what made me switch to the newer style with shellholders! I never could maintain consistency with the collets.

If you can afford the cost.... a Gracey or a Giraud trimmer is about the best there is.