Cartridge Trimmer- measurements vary?

[gifbohane]

Guys

I just bought a manual cartridge trimmer to trim 223. I set it up to trim to 1.750. The first few carts are fine then the rest trim shorter and shorter. I wind up grinding them a low as 1.744. I tried once to keep going on an older cartridge and it ground down to below 1.732 when I quit grinding. I have a theory that the brass trimmings left on the teeth of the trimmer head (and there are a lot) are altering the results. Sometimes I can only trim to 1.752 and I have to change the setting. Then the next one is too short at 1.748. I have gotten to the point of ball parking the time spent trimming on each case to get to the desired trim length. Any thoughts on my problem?

Also is a variation from 1.744 to 1.755 acceptable?

 

[243winxb]

Make & model of trimmer?

Also is a variation from 1.744 to 1.755 acceptable?

No, not acceptable to me.

223 brass is ok to use with trim length as short as 1.740" A SAAMI standard.

 

[Infidel]

.... Also is a variation from 1.744 to 1.755 acceptable?

Not to me. "Grinding"? The trimmers that I have and have seen cut, not grind. What kind of trimmer?

 

[buck460XVR]

Guys

I just bought a manual cartridge trimmer to trim 223. I set it up to trim to 1.750. The first few carts are fine then the rest trim shorter and shorter.

I have a theory that the brass trimmings left on the teeth of the trimmer head (and there are a lot) are altering the results.

Sounds like the stop is moving, more than the shavings affecting the cutter. Now if the shavings are getting in the shell holder, I might see the length getting a little shorter.But not progressively. That sounds like a stop issue.

 

[higgite]

First, to nit pick nomenclature, you’re trimming cases not cartridges. At least, I hope so.

Sounds like the stop is either moving or isn’t set for the desired case length. It might help us to help you if we knew what model of trimmer you’re using and how you went about setting it up.

 

[Walkalong]

Also is a variation from 1.744 to 1.755 acceptable?

As others have said, no. Usable? Yes, but we want to find and fix the issue.

What trimmer?

 

[gifbohane]

It is the LE Wilson. The set screw is binding down well onto the shaft of the distance measurement. The set up seemed straightforward but I am certainly doing something wrong. First case comes out, after adjustments, at 1.750. After that first one anything can register.. perhaps I am pressing the crank too hard inward toward the case? The videos show you can crank all day after you reach the furthest point forward, it just spins. Maybe I need to whale on the hold down screw?

 

[Walkalong]

The Wilson should have very little to no variance. My guess is you did not trim some of them all the way. Whale away? No, Steady pressure until it stops taking off brass? Yes.

 

[Scooter22]

I just looked at the video and don't see how the length could change. The stop the case head contacts is threaded so the case would have to spin to have to actually turn it. Look and see is the case is spinning but If it's locked tight I don't see that happening. Maybe your pressing too hard when cutting but I still don't see that turning. But If you have some kind of contamination between the base of the case and the stop that would push the case farther forward causing it to get cut shorter. So make sure those two surfaces are clean of powder grains, tumbler reside, brass trimmings ect. Also are the cases deprimed? A protruding primer will also push the case closer to the cutter.

 

[higgite]

I have that trimmer and it is very consistent. Some suggestions:
1. Make sure you’re using the right case holder. They are different for fired or resized brass.
2. Make sure you tap the case solidly into the case holder. Don’t need to hammer it, but do firmly tap it.
3. Make sure the case stays snug against the backstop when you clamp the case holder down. It will move if you aren’t careful. (Don’t ask how I know that.)
4. Like Walkalong said, no need to whale away at it. Just steady pressure on the crank until it quits cutting brass.

 

[gifbohane]

Excellent suggestions Thanks and yes I bought the case holder for previously fired brass.

higgite- I think that you meant to say previously fired and "new" brass???

 

[higgite]

Excellent suggestions Thanks and yes I bought the case holder for previously fired brass.

higgite- I think that you meant to say previously fired and "new" brass???

New or resized use the same holder. As opposed to fired but not resized.

 

[gifbohane]

AHA so if I fire a round and do not resize it, I require a different case holder. But won't the case length dimension change once I then deprime and resize it?

 

[243winxb]

From the instructions.

Occasionally we have a case holder returned as “defective”, because the case drops in clear to the head and still is not tight. Almost invariably these so-called “defective” holders are in .30-30, .32 Spl., .300 savage, or .243-.308-.358 Winchester.

Standard holders in these calibers are made for FIRED
cases and cannot be used for both new and fired. Holders for new cases in these calibers are now stocked, are marked “NEW CASES” and can be had at standard prices.

Unless holders for new cases are specified, however, the standard holder for fired cases will be furnished. In almost all calibers, only 1 holder is required for both new and fired cases, the definite exceptions being the calibers listed in the paragraph.

 

[243winxb]

But won't the case length dimension change once I then deprime and resize

Yes is my guess. I have a Lyman.

 

[Bandit67]

I don't use the Wilson but I always trim AFTER resizing. Makes no sense to me to trim a fired case that hasn't been resized.

 

[gifbohane]

I am coming to the conclusion that while your suggestions are making the process better, my biggest problem is MY ability to make consistent measurements with the Hornady calipers. Measure it three times and get three different numbers... all close 009 010 011 close but not exact.

 

[lightman]

I have a Wilson and its very accurate. It sounds like your cutter may be dull. I bought the carbide one and it makes nice clean cuts easily. It was somewhat expensive! The suggestion of sizing and depriming the case before trimming is a good one.

 

[higgite]

AHA so if I fire a round and do not resize it, I require a different case holder. But won't the case length dimension change once I then deprime and resize it?

As others have already responded, yes, resizing will increase the case length vs a not resized case, so if you full length resize your cases, resize before you trim. The case holders for fired but not resized cases are for those who only neck size their reloads to fit a specific rifle, as opposed to those who full length resize before trimming.

 

[Walkalong]

You should always size before trimming anyway.

 

[Scooter22]

I know Wilson makes top notch stuff but the set up of the trimmer w/ the floating case holder, plus both stop and cutter variable, seems a bit confusing to set up. I have a Forrester trimmer I've used with zero problems and consistent trim lengths since I started reloading in the 70's.

 

[higgite]

I know Wilson makes top notch stuff but the set up of the trimmer w/ the floating case holder, plus both stop and cutter variable, seems a bit confusing to set up. I have a Forrester trimmer I've used with zero problems and consistent trim lengths since I started reloading in the 70's.

If you have used a Wilson, it's not confusing at all. I don't know what cutter variable that you're talking about. There is no adjustment required on the cutting end of the Wilson. You adjust the stop and that's it. I have owned and used both Wilson and Forster trimmers and both are top notch quality products, but I find the Wilson to be a lot less fiddly to set up or change calibers. ymmv

 

[Carl N. Brown]

My only experience with a manual trimmer (for 30-30) indicated to me that the trimmed length depended on the thickness of the cartridge head to be consistent. The cutter was positioned by a stud entering the flash hole from the mouth of the cartridge. Burrs on the flash hole (or depressions from over-zealous de-priming) could give variations in trim length.

 

[Scooter22]

If you have used a Wilson, it's not confusing at all. I don't know what cutter variable that you're talking about. There is no adjustment required on the cutting end of the Wilson. You adjust the stop and that's it. I have owned and used both Wilson and Forster trimmers and both are top notch quality products, but I find the Wilson to be a lot less fiddly to set up or change calibers. ymmv

Maybe I didn't watch the vid carefully but the guy said to set the cutter out about .010 then adjust the stop. So I was thinking both have to be adj.

 

[higgite]

Maybe I didn't watch the vid carefully but the guy said to set the cutter out about .010 then adjust the stop. So I was thinking both have to be adj.

What video did you watch? Have a link?
The main difference in the two trimmers is that the Forster's case "stop" is fixed and the cutter stop is adjustable, but the Wilson's cutter stop is fixed and the case stop is adjustable. Just two different ways to skin a cat.