New to Giraud, have question...

[DngBat7]

So I am new to giraud, have a few quick yes or no questions.

1. Feel slight, slight, slight burrs when done. Is it acceptable to give a quick wipe with some fine steel wool to smooth out case mouth?

2. If I rotate a trimmed case on calipers, it varies by .0005, I assume that is more than acceptable to fclass or benchrest standards.
(Tho I assume that can be corrected through my technique of getting better of pushing down case in to holder when trimming?)

3. If I have 2 batches of brass in the same caliber, and the necks of one batch were turned slightly thinner than the other batch, I assume it’s a different cutter setting and should get a different cutter instead or resetting cutter each time I switch brass I’m trimming. (I feel I already know the answer to this)

 

[Ccrider]

Which trimmer are you using?

 

[DngBat7]

Which trimmer are you using?

I guess I should have noted that. The big unit.

 

[Turbulent Turtle]

So I am new to giraud, have a few quick yes or no questions.

1. Feel slight, slight, slight burrs when done. Is it acceptable to give a quick wipe with some fine steel wool to smooth out case mouth?

2. If I rotate a trimmed case on calipers, it varies by .0005, I assume that is more than acceptable to fclass or benchrest standards.
(Tho I assume that can be corrected through my technique of getting better of pushing down case in to holder when trimming?)

3. If I have 2 batches of brass in the same caliber, and the necks of one batch were turned slightly thinner than the other batch, I assume it’s a different cutter setting and should get a different cutter instead or resetting cutter each time I switch brass I’m trimming. (I feel I already know the answer to this)

I've been using mine for about 4-5 years now. I use a Mechanix glove on my right hand to hold the cases. After you do a few hundred, you will understand why.

I put in the case firmly but not pushing down hard. Use the same pressure all the time. I twist the case once it's in the machine, about a half turn and continue turning as I pull it out. No burrs, no nicks, just nice.

If you want to wipe with 0000 steel wool, it can't hurt. I don't unless the case is dirty or has something on it. I do that first, before any processing.

 

[rardoin]

That is about the variance I get in OAL. I don't have any concerns about the very slight roughness felt if I drag a fingernail along the case mouth; it has not influenced the bullet seating or cartridge feeding whatsoever. I push in lightly and twist, like sharpening a pencil, until the cutter is not taking off any material. You will know this by the sound/vibrations felt. I stop my trimming when each case has the same sound/feel...if you know what I mean. Like Turbulent T I also shoot F-class and process up to 300 cases in a session. Unlike Denys, I don't use gloves...real men don't find the need. My hand does get a little cramped after 100 or so and I take a little break and do something constructive...like measure and weigh primers.

Robin

 

[Ned Ludd]

Not sure what you mean by "rotating a case on calipers". What varies? Is it the case length? The depth of the bevel/chamfer around the case mouth? Just not sure what you mean. I have the Gireaud set up so that the mouth of the case holder is facing up. It might seem awkward at first, but I think it works better that way than having the mouth of the case holder horizontal (pointing at you) for several reasons.

I hold the case firmly down at the bottom of the holder and generally give it 3 - 4 twists with my fingers before moving on to the next case. Note that this is not 3 - 4 complete turns, just as far as I can turn it with my fingers 3 - 4 times, so maybe a couple to 2.5 complete turns or so. You can easily feel when the blade is no longer removing much material from anywhere around the case mouth. Obviously, trimming/chamfering virgin cases for the very first time requires noticeably more effort than re-trimming those that have already been trimmed once (or more) on subsequent brass preps, because you're removing far less material. If you examine the design of the cutter head and blade and pay careful attention to the fact that the blade is rotating completely around the case mouth, you'll understand why you need to turn the case completely around to ensure the chamfer/bevel is uniform all the way around the neck.

The other thing to remember is that the Giraud trimmer indexes off the case shoulder, not the base of the case. Any variance in case base-to-shoulder (CBTS) measurement will show up as case overall length variance after trimming with the Giraud. In my hands, CBTS measurements are very uniform after re-sizing with a full-length bushing die, typically, less than 0.0005" to 0.001" for ten randomly selected cases. Nonetheless, there will always be some measurable case length variance due to the fact that the Giraud indexes off the shoulder, not the base of the case. The best advice is always to keep your re-sizing/brass prep as consistent as possible.

As far as the cutter blade setting, you are correct. Different neck turning thickness may necessitate adjusting the blade to maintain a similar inside/outside chamfer, as can changing brands of brass with different neck wall thickness. Setting up the cutting blade to the exact inside/outside chamfer desired and practicing using cheap throw away brass with a different thickness than Lapua match brass will only ensure that you become more proficient at adjusting the blade, as it will not be set up correctly for the Lapua brass and you will have to go through the whole procedure over again (ask me how I know this). I personally find adjusting the cutter blade to be a bit of a PITA, so I might be tempted to buy an additional cutter head or two. However, at $50 a pop, that could end up being a fairly expensive approach if every batch of brass that you neck turn ends up with sufficient variance in the neck wall thickness that it requires a different blade setting (or different cutter head assembly). I would suggest that trying making your neck-turning process more uniform might also be an acceptable approach that would save you some $$$ and effort.

 

[MN50Shooter]

If you watch Giraud's video he mentions using a piece of Scotchbrite and placing the mouth of the case down against it, and giving a slight rotation. He indicates that it will remove the sharp edge/burr and I believe you'll find it alleviates your issue .

 

[Turbulent Turtle]

That is about the variance I get in OAL. I don't have any concerns about the very slight roughness felt if I drag a fingernail along the case mouth; it has not influenced the bullet seating or cartridge feeding whatsoever. I push in lightly and twist, like sharpening a pencil, until the cutter is not taking off any material. You will know this by the sound/vibrations felt. I stop my trimming when each case has the same sound/feel...if you know what I mean. Like Turbulent T I also shoot F-class and process up to 300 cases in a session. Unlike Denys, I don't use gloves...real men don't find the need. My hand does get a little cramped after 100 or so and I take a little break and do something constructive...like measure and weigh primers.

Robin

WWT, I'm not going to let you get away with such a snarky remark.

Actually the glove helps stave off the onset of a cramp in my hand. Also, I'm protecting my trigger finger as I am incredibly non-ambidextrous; hopelessly right-handed.

And consider it a tribute to Michael Jackson.