Feedback about the Giraud trimmer

[Brians356]

If a reloader understood the Wilson case gage it would not be necessary to have 4 pages of responses.

That would be true, if understanding the Wilson case gage had anything to do with feedback about the Giraud trimmer. As usual, you've cut to the very heart of some matter, somewhere.
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[fguffey]

These type trimmers {shoulder indexing} work great if you have a lot of brass to trim because they are fast. If the brass is very consistent in its hardness or anneal and all the cases resize to the dead on headspace you want then they should and will trim up very consistent and be dead on the length you set

It is possible to have a chamber that is long from the shoulder to the bolt face, Wilson designed the L.E. Wilson case gage to prevent the reloaders from having to deal with it. Again, all a reloaders is required to do is understand the function of the Wilson case gage.

F. Guffey

 

[1shot]

OK all,
I just my Giraud power trimmer and spent several hours getting acquainted with it. I can now say from hands on experience that it is possible to get a "cookie cutter" or knife edge on the case mouth, but to do so means the cutter isn't aligned properly. That said, a little patience in your set up will alleviate this problem. Using a pair of magnifier glasses (so these old eyes can see) I was able to adjust the cutter blade to get a 40/40/20 or most any combination chamfer/de-burr on several diameter cases. I think the reason Giraud set this machine up in two different configurations is to allow ease of tuning the cutter. I have found t is much easier to do the when the cutter is in the horizontal orientation.
I first loosened the set screw holding the cutter slightly then pressed a case against it to hold it in place. I then used a tooth pick to gently move the cutter slightly in or away from the center of the case. Then I tightened up the set screw and hand turned the cutter on the case a couple of revolutions while keeping light pressure on the case. All said, it might have taken 15-20 min. to do the first caliber. The next two went progressively faster.
Using the locking die ring method, I can now switch calibers in a few minutes.
I hope this helps,

Lloyd

 

[jlow]

Lloyd –I just got my Giraud power trimmer today too and if you look at my post and pictures at the other thread here:

http://forum.accurateshooter.com/threads/giraud-trimmer-knife-edge-debunked-with-photos.3911804/

You will notice that the interface between the two cutting surface is round i.e. it is designed to NOT give a knife edge, in fact, based on that design, it is impossible to get a knife edge.

I am also not sure why you want to do a 50/50? The purpose of a deburr is just that to take the burr out and as such, you do not need to have a sharp angle, just enough of an angle so that the case does not catch as it goes up the feed ramp – something like what the blue arrow is pointing to in this rough cross-section I made of a case neck/boat tail bullet. On the other hand, the purpose of a chamfer is to reduce the chance that a bullet will be shaved by a sharp transition. So for that standpoint, this is the whole rational to make VLD chamfer tools that we buy, i.e. you need a sharper angle so that the transition between the opening and the inside of the case is gentle i.e. where the red arrow is pointing to.

 

[1shot]

jlow,
I should have been more precise in my description. I should have said 40/40 20 as it a tri-way cutter after all. That said given enough force it does make the edge of the case mouth much sharper than if you had not done the case at all. I do know this machine will be put to use soon!
Thanks,

Lloyd

 

[Brians356]

Lloyd –I just got my Giraud power trimmer today too and if you look at my post and pictures at the other thread here:

http://forum.accurateshooter.com/threads/giraud-trimmer-knife-edge-debunked-with-photos.3911804/

... the whole rational to make VLD chamfer tools that we buy, i.e. you need a sharper angle so that the transition between the opening and the inside of the case is gentle i.e. where the red arrow is pointing to.

WRT your excellent drawing (bullet juxtaposed with chamfered case mouth), a few couple of questions [Groans from the peanut gallery - take a smoke break, fellas.]:

1. What app do you use to create your drawings?

2. How thick are your neck walls? (I presume you turn them to some desired thickness, or know the thickness.)

3. How many thousandths below bullet diameter do you size your necks (before seating)?
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[jlow]

WRT your excellent drawing (bullet juxtaposed with chamfered case mouth), a few couple of questions [Groans from the peanut gallery - take a smoke break, fellas.]:

1. What app do you use to create your drawings?

2. How thick are your neck walls? (I presume you turn them to some desired thickness, or know the thickness.)

3. How many thousandths below bullet diameter do you size your necks (before seating)?
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Adobe Illustrator.

As to dimensions.... They are in no way meant to be to scale..... Just to illustrate a ROUGH point....

 

[Brians356]

As to dimensions.... They are in no way meant to be to scale..... Just to illustrate a ROUGH point....

Ahh. But the proportion of chamfer vs deburr, and their respective depths of cut, and the position of the narrow peak between them seems fairly representative, wouldn't you agree?

But I see what you mean about the other aspects of the drawing. For example, the neck ID appears to be sized one full neck wall thickness smaller than bullet OD (e.g. if your neck walls were .012" thick, the neck depicted would have been sized a full .012" smaller than bullet OD. Yikes!) Of course then the very wide chamfer depicted here would actually be required, to form a funnel wide enough to encompass the full width of the bullet, and ease entry into the neck opening. In the real world, of course, few if any of us size necks so small that a chamfer that cuts more than halfway through the neck walls would be required, so, yes, the drawing is obviously only a rough depiction.
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[jlow]

Ahh. But the proportion of chamfer vs deburr, and their respective depths of cut, and the position of the narrow peak between them seems fairly representative, wouldn't you agree?

But I see what you mean about the other aspects of the drawing. For example, the neck ID appears to be sized one full neck wall thickness smaller than bullet OD (e.g. if your neck walls were .012" thick, the neck depicted would have been sized a full .012" smaller than bullet OD. Yikes!) Of course then the very wide chamfer depicted here would actually be required, to form a funnel wide enough to encompass the full width of the bullet, and ease entry into the neck opening. In the real world, of course, few if any of us size necks so small that a chamfer that cuts more than halfway through the neck walls would be required, so, yes, the drawing is obviously only a rough depiction.
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I think if anything looks representative, it was purely accidental. The drawing was only meant to show the approximate difference in the angle of the different cuts.

 

[ireload2]

The vast majority of handloaders have long and productive reloading lives and never see or know a thing about Wilson gauge.

It is possible to have a chamber that is long from the shoulder to the bolt face, Wilson designed the L.E. Wilson case gage to prevent the reloaders from having to deal with it. Again, all a reloaders is required to do is understand the function of the Wilson case gage.

F. Guffey

 

[Brians356]

I think if anything looks representative, it was purely accidental. The drawing was only meant to show the approximate difference in the angle of the different cuts.

Of course. The drawing notwithstanding, your photo indicates the chamfer removes well more than 1/2 of the neck wall thickness at the end of the neck (on the side opposite, where the chamfer was fully completed.)

My point is that if, for example, a neck ID is sized .002" smaller than bullet diameter, a chamfer only needs to cut less than .002" into the neck wall (or less than 1/6 of the total wall thickness for a .012" wall) in order to encompass and funnel the bullet smoothly.
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[dedogs]

The vast majority of handloaders have long and productive reloading lives and never see or know a thing about Wilson gauge

Isn't this the same thing as a "Gizzie" A short piece of the barrel with the appropriate reamer run into it to use as a gauge for shoulder bump? The only advantage I can see to the Wilson gauge is it tells you when you NEED to trim (providing you have a SAAMI spec chamber). dedogs

 

[Brians356]

Isn't this the same thing as a "Gizzie" A short piece of the barrel with the appropriate reamer run into it to use as a gauge for shoulder bump? The only advantage I can see to the Wilson gauge is it tells you when you NEED to trim (providing you have a SAAMI spec chamber). dedogs

A Wilson case gage is a two-ended affair. It tells you if you have an "innie" or "outie" at both ends of the case. The base end is stepped to indicate within SAAMI min and max headspace. The neck end is somewhat less precise, since it's referencing the shoulder as well, and thus doesn't indicate SAAMI case "trim-to" or "max" case length directly.
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