Case Trimmer

Dirty Harry · Posted: Sat Aug 12, 2006 2:11 pm Post subject: Case Trimmer

Gentlemen,

I have found that trimming cases to the perfect length is one of the most trying aspects of reloading. I almost always wind up a tad short. Mad

I am considering buying either the Sinclair trimmer or the Redding trimmer with the micrometer on it. Both claim to trim a case down to a gnats backside.

Has anyone had some experience with either of these or any other precision trimmer?

Thanks
Harry

mc223 · Posted: Sat Aug 12, 2006 3:23 pm Post subject: Re: Case Trimmer

I made my trimmer. It indexes off the datum of the case. Sinclair sells a very similar device called Possum Hollow Kwick Trimmer. The sell for 12.95.
There is also a motorized trimmer called the Gracey. Im not sure of where the Gracey can be aquired.
The one I use goes in a bench top drill press. Very Quick and easy to do a lot of brass accurately. My cases finish with less than .003 variance in overall length.

popgun · Posted: Sun Aug 13, 2006 9:36 am Post subject: Re: Case Trimmer

Harry,
Seeing that you are a BR shooter I guess the Gracey trimmer would not be what you are looking for. The Gracey trimmer is a power unit and it does give uniform results but it is intended more for the volume shooter. That's not to say BR shooters don't shoot allot and it might be just what your looking for but I know you probably like to fuss allot over each case. A friend in Tennessee set a 600 yd BR record this year and he uses several Gracey trimmers.

Here is the link to the Gracey trimmer.
OK Weber, Inc dba Match Prep

Dirty Harry · Posted: Sun Aug 13, 2006 10:26 am Post subject: Re: Case Trimmer

popgun wrote:

Harry,
Seeing that you are a BR shooter I guess the Gracey trimmer would not be what you are looking for. The Gracey trimmer is a power unit and it does give uniform results but it is intended more for the volume shooter. That's not to say BR shooters don't shoot allot and it might be just what your looking for but I know you probably like to fuss allot over each case. A friend in Tennessee set a 600 yd BR record this year and he uses several Gracey trimmers.

Here is the link to the Gracey trimmer.
OK Weber, Inc dba Match Prep

Actually, I hate case prep but unfortunately it is a necessary evil and consistency is most important in BR. I looked at the Gracey and it appears to do the job but it's just a wee bit too pricey for me. Did you checkout the size of that motor? Geez, you could use that puppy on a band saw. <G>

At any rate it looks like the Sinclair precision trimmer is the ticket for me.

Thanks
Harry

SwampFox · Posted: Mon Aug 14, 2006 12:35 pm Post subject: Re: Case Trimmer

Harry,
The best tool I have found for precision trimming is the CH Tool trimmer. It allows you to square the base and trim the mouth. Trimmed cases are the same, every time. I square the base first time and then trim only the mouth after.

Like most tools it has a drwaback, you need a case holder for just about every cartridge except the 308 and 30-06 varants. The body is held friction tight by the holder, then the flat bolt face is adjusted to trim. It is pretty fool proof.

I now use the RCBS pro trimmer and have found that it does a very good job, especially the 3 way trimmer heads. I have one of the case prep stations as well, when used in unison, they make short work out of the most boring part of reloading.
Ed

yzchamp · Rookie Member Joined: Apr 27, 2006 Posts: 20

how important case triming is? dos it matter is you get them little to short after full sizing ?

SwampFox · Posted: Thu Aug 17, 2006 3:45 am Post subject: Re: Case Trimmer

YZ,
It depends on how short you end up in a non crimped case. For a cartridge case that requires crimping, like a 357 Mag, case length uniformity is a must for accuracy. The amount of crimp in a roll crimp die, is based on the length of the case.

I once trimmed 250 rounds of 44 mag brass too short, but all the same length. I just segregated the brass and set up dummy rounds for that brass. There was no real difference in accuracy VS full length brass. But, the brass was uniform in length and that is the key.

What Dirty Harry was describing was brass that when trimmed, was not uniform. This is a common problem with trimmers, like the Forrester, that have a collet that squeezes onto the rim and sets the length at the same time. If the rims are different in diameter, the length is different.
Ed

Arizona Hunter · Member Joined: Jul 22, 2006 Posts: 275

I have the inexpensive but usefull Lee trimmer that I attch to my 3/8" drill. They trim down to "suggested maxium length" and that is all. For trimming further I have the Redding 1200, but it is painful getting it set. The new Redding 2400 has a "dial in" feature that I may switch to.

For big game hunting, and even varmints both work fine-but for BR I think something more precise is needed.

scratcherky · Posted: Mon Sep 11, 2006 1:54 pm Post subject: Re: Case Trimmer

I like the Lee trimmer. It is simple and almost foolproof. I use it in a Shopsmith lathe.

Gil Martin · Posted: Mon Sep 11, 2006 5:18 pm Post subject: Re: Case Trimmer

I have been using Lee trimmers for many years and they work well. For heavy duty case trimming I have a Wilson lathe trimmer. All the best...
Gil

george20042007 · Posted: Mon Sep 11, 2006 10:55 pm Post subject: Re: Case Trimmer

I don't know who made my case trimmer, I've had it for more than 40 years. It's made of brass & it has a hand crank on it. It's adjustable for what you want and you stop cranking when it no longer cuts the metal. A simple device for sure and very accurate. I only trim after the brass has been fired 4 times, or when I have bullet seating problems.
Keep it coming...

Vince · Posted: Tue Sep 12, 2006 5:53 am Post subject: Re: Case Trimmer

I have an older RCBS Trimmer. It uses a collet to hold the case head and is adjustable for trim length. Had it for 25 years and it works well for me.

I keep a vernier caliper on the bench and check every case before it goes in the trimmer. The trimmer is set to maximum case length and I use it as a Go/No Go type gauge. Only those cases that need trimming get trimmed. I also check each case as it comes off the trimmer for consistency.

I have never had a problem with inconsistent lengths, but then again I followed the instructions that came with the trimmer. One of the instructions is to not put excessive pressure on the crank when trimming. If you do, it will trim just a little more off....short case.

I think that all trimmers are pretty good.....it just comes down to the "nut behind the butt". If we do our part, and a big part of that is following the instructions, then they should work well and give consistent results.

Cheers, Vince

bradking1 · Member Joined: Mar 03, 2005 Posts: 53

I have the same trimmer as Vince and have had no problems with it. As for setting it up for different cartridges, i will usually size a once fired case, measure it and if it is at a length i want i just keep it in die box. So when it comes time to trim cases, i pull that rascal out, put it in the collet, loosen the adjustment rings, slide it up to the cutter and then re-tighten the rings, remove it and start trimming cases.

As for trimming bottleneck cases i only size when the get out of spec. they will last longer. i also have some custom rifles with minimum dimension chambers and the cases just don't seem to grow much, if any in these rifles.

for example i have a 7mm STW and i am shooting cases that have been reloaded at least 5 or 6 times...have never trimmed them...still within specs. on the other hand i had a 25-06 that required trimming every 2nd reload. i figure the chamber was more toward the maximum chamber dimension.

Just my .02

Brad

dlsjm · Rookie Member Joined: Sep 22, 2006 Posts: 2

I wonder if after trimming cases such as 357 and 44 mag for example say .010" shorter than recomended, to what degree would this affect the pressure levels when using a maximum powder charge. Very Happy

PaulS · Posted: Sun Sep 24, 2006 12:20 am Post subject: Re: Case Trimmer

If you use the same overall length nothing will change. If you seat the bullet the additional .010" then pressure will rise. How much it rises is a function of the powder used, the air space lost, and the proximity to a maximum published load. It could be un-noticable to dramatic in the additional pressure generated. That might be equivalent to a 3 grain overload (about 18%).