variations in trimming with giraud.

[Germz]

Not sure what I'm doing incorrectly here.

I sort all my .223 brass by headstamp. This last batch I did was all PMC (to include different runs of PMC).

I have my RCBS F/L die in my LnL AP press so that its touching the shellplate, without a casing inserted.

When I go to trim on my giraud, sometimes it will trim to 1.750..
other times brass that is 1.760+ will only trim down to 1.755ish
other times brass will trim all the way down to 1.744ish.

its not that big of an issue but i'm concerned...especially since I should be getting 1.750 after what I paid for.


Am i resizing incorrectly?
are these differences to be expected when dealing with different runs of the same headstamp?

lets discuss!

[longrange99]

Hey Germz - after resizing, did you by chance use a case comparator? This will tell you how consistent your resizing is, and to which length you are resizing. The other thing with the AP is shell plate tension. If the bolt that holds on the shell plate is loose at at all you will induce variation.

[Germz]

I do not have a case comparator, I checked to ensure the retaining bolt is just over hand tight.

Die setup per hornady is die just touching the shellplate.
Die setup per RCBS is die touching shellplate, then 1/4 of a turn MORE in.

not sure if this is an issue either.

[ditchdigger]

Is your sizing die set consistently? Check with a comparator.

The Giraud will trim based off of the shoulder. Different shoulder bump, different trim length.

Do you have a lock ring on your Giraud case holder? This helps with consistency.

Even if you do these things you should check your OAL and make minor adjustments if necessary.

[Mr. Casull]

I have the same problem with mine. I think it has to do with brass that was shot in different guns. I end up checking each one to see if it at least is within a couple of thousandths of what it should be. The only sure trimmer to be 100% accurate is the RCBS that trims off of the length of the brass. But the RCBS is so slow it was driving me crazy so I bought the Giraud.

[damndave]

The Giraud should be accurate to within +/- 0.002. More than likely an issue with the resizing.

[popeye4]

Get one of these: http://www.sinclairintl.com/reloadin...prod34014.aspx

Without proper measuring tools, you can't really determine what the quality is of your brass prep steps. I like the Sinclair vs. the Hornady as the Sinclair gauges are made of steel and shaped to conform to the shoulder angle of the cartridge being measured.

[Waldog]

I have the Giraud. I can trim my 223 cases +/- .002. It takes a little practice. I suspect your problem is a sizing issue.

[buffybuster]

The Giraud indexes off the shoulder. If you're getting inconsistent trim lengths, that most likely due to inconsistent shoulder bump.

[Germz]

I don't doubt that it probably was my die setup for resizing. regardless. all the brass chambers and its all <100yard plink ammo anyway.

[Jasonaspears]

I noticed my sizing die wasn't set properly and caused a similar issue. Fixed that issue and now everything sizes within spec on the trimmer.

[tiller]

I don't doubt that it probably was my die setup for resizing. regardless. all the brass chambers and its all <100yard plink ammo anyway.

It's not a sizing issue.... I'm going to go out on a limb and say that your trying to process some range pick up as well?

It's not a sizing issue... It's a chamber issue... Every chamber is different has the slightest different angle, shape , and size compared to the next...


And now I will wait for the comments that say " but sizing bumps the shoulder back to the same spot"


Take 50 pieces of brass fire from YOUR CHAMBER size them and test them in the trimmer... I'm sure you will see the results you want... Then go back to trimming range pickup and you will see where your problem lies....

( I had this exact same problem with 300 black in the wft which trims the exact the exact same way)

[Jasonaspears]

It's not a sizing issue.... I'm going to go out on a limb and say that your trying to process some range pick up as well?

It's not a sizing issue... It's a chamber issue... Every chamber is different has the slightest different angle, shape , and size compared to the next...


And now I will wait for the comments that say " but sizing bumps the shoulder back to the same spot"


Take 50 pieces of brass fire from YOUR CHAMBER size them and test them in the trimmer... I'm sure you will see the results you want... Then go back to trimming range pickup and you will see where your problem lies....


( I had this exact same problem with 300 black in the wft which trims the exact the exact same way)

So FL sizing set up properly doesn't reset the brass to a factory spec?