• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Giraud trimmer question. When to trim?

DngBat7

Silver $$ Contributor
I know it’s a dumb question. Was wondering do you trim with giraud before or after sizing brass? I am assuming after it is sized.
 
I trim after sizing and after every cleaning in pins to trim away any peaning at case mouth. Most of the case holders I have are cut with the finishing reamer so the case won't fit properly until sized. Rick M.
 
I trim after sizing and after every cleaning in pins to trim away any peaning at case mouth. Most of the case holders I have are cut with the finishing reamer so the case won't fit properly until sized. Rick M.

Where'd you get the blank inserts you finished with the reamer?
 
Yes, after sizing. And even more important than the fact that it indexes off the shoulder is the fact that the cutter head is set for a specific case mouth diameter. If you tried to trim unsized brass the chamfer debur would be all messed up because the diameter of the mouth would be too large.
 
Yes, after sizing. And even more important than the fact that it indexes off the shoulder is the fact that the cutter head is set for a specific case mouth diameter. If you tried to trim unsized brass the chamfer debur would be all messed up because the diameter of the mouth would be too large.

I'll add to Sheldon's observation that varying neck wall thickness with different brands of brass can also make a big difference in the inside/outside chamfer obtained with the Giraud. There are several nuances to using the Giraud that are markedly different from more conventional case trimmers, but the end results are most definitely worth the learning curve.

Like everyone else, I trim/chamfer after re-sizing as the very last step in the brass prep process.
 
Yes, after sizing. And even more important than the fact that it indexes off the shoulder is the fact that the cutter head is set for a specific case mouth diameter. If you tried to trim unsized brass the chamfer debur would be all messed up because the diameter of the mouth would be too large.
I though I was asking a dumb question, But this is why I asked. Never would have thought of this.
 
Not a dumb question at all
The only dumb question is... "Did I really do that last night"?:eek::oops:

What you need to do is get the actual "measured length" of YOUR chamber. That way, you'll know if you really need to trim. Most chambers are cut .020" longer than Max Trim Length. And depending on the type of die you use, you may not need to trim for a looong time. I have BR brass with 25+ resizes that still don't need trimming. All sized with Forster Precision Bush Bump Dies. Brass doesn't get a chance to grow like standard dies with the neck button that pulls the necks longer with the up stroke. YMMV.
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,177
Messages
2,190,857
Members
78,721
Latest member
BJT20
Back
Top