Giraud Trimmer Problems?

[PJ1]

Could be I'm doing things wrong, but when I'm trimming new brass (Alpha, especially) to length, there seems to be quite a variation in final cut with those pieces. I'm aiming for 1.910" trim length, but on longer pieces of the Alpha brass >1.913", I end up with 1.909" to 1.907" for the final length. Those pieces at < 1.913" end up at the 1.910" that I want.

Could this have something to do with the bushing? I've checked for play with the shaft and cutter head and there seems to be none. This is an older Girard, but it has received very little use until recently.

 

[rijndael]

The Giraud indexes off the shoulder. So, it's measuring/trimming from shoulder to case mouth, but you're measuring the total length.

Your brass likely has varying shoulder to base (headspace) measurements, causing varying OAL measurements.

 

[PJ1]

Good idea. So I assume that I should be FL sizing the new brass before trimming?

Thanks for your help.

 

[rijndael]

So I assume that I should be FL sizing the new brass before trimming?

You need to have the shoulder pushed out to your chamber (ie. fired), don't push them all to the shortest new measurement. I would trim it twice if the variance is too great for your preferences.

Trim when new so you can get a chamfer and deburr, to make sure you don't send a burred piece in to your die. You also want the internal chamfer for initial seating / expanding.

You can re-trim it after you've fired it and have a more consistent shoulder measurement.

 

[Sebrock]

Good idea. So I assume that I should be FL sizing the new brass before trimming?

Thanks for your help.

Before my Giraud I would use a WFT and an RCBS case prep center for chamfering/debrurring and brushing the necks. When I get new Lapua brass (which all varies slightly at the shoulder) the only thing I do is slightly expand the neck with a mandrel, chamfer and then brush the neck. I wont trim until my brass is properly sized to the chamber (which takes a few firings - I also wont push back the shoulders till this happens). I think its a good idea to have a separate chamfer/debur tool because you dont always have to trim but its alway a good idea to chamfer.

 

[Hoser]

That is one more reason why I am glad I have a Henderson now.

I felt like I was chasing my tail sometimes with my Giraud. That said, it is a really good trimmer and sped up my reloading process quite a bit.

 

[Turbulent Turtle]

My new brass regimen is similar to @Sebrock 's, except that after the mandrel treatment, I use my Giraud trimmer but only to give the brass a slight chamfer/deburr. I don't push the case much into the Giraud, I just lightly hold it to give it the slight chamfer treatment. I'm not looking at trimming close at this time. Of course, if there's a longish case, it will get trimmed back a bit.

After the first firing and F/L resizing, I process the cases normally through the Giraud; at a very high rate of speed: 100 cases trimmed, chamfered and deburred in about 5 minutes.

 

[Sniper338]

That is one more reason why I am glad I have a Henderson now.

I felt like I was chasing my tail sometimes with my Giraud. That said, it is a really good trimmer and sped up my reloading process quite a bit.

Why do you like to trim and measure by OAL?

 

[PJ1]

Thanks to all. I was really surprised to see the condition that the Alpha brass in 6.5 CM came in. All of the mouths have a nasty mushroom that has to be de-burred. All part of my education process.

 

[RegionRat]

Thanks to all. I was really surprised to see the condition that the Alpha brass in 6.5 CM came in. All of the mouths have a nasty mushroom that has to be de-burred. All part of my education process.

Yes, lessons in bulk virgin brass.

When brass is shipped loose this is common. Unless it is protected right after prep, there is a risk the case mouths get some dings or even worse. The damage can even start before shipping if the brass is dropped into bulk bins after prep.

Some shipments have very low damage, but others may have been damaged by rougher shipping. You have to guard against this by assuming it will happen.

Some folks don’t care at all and let the bullet fix the brass, but others go as far as running a complete prep and chamfer on virgin necks, especially folks who turn virgin necks. Lots of variation between doing nothing at all, or full prep.

You can pretty much count on needing to detail bulk-shipped virgin brass with rounding and chamfering if you care about these issues.

 

[Turbulent Turtle]

Thanks to all. I was really surprised to see the condition that the Alpha brass in 6.5 CM came in. All of the mouths have a nasty mushroom that has to be de-burred. All part of my education process.

Pictures? Whan kind of mushroom are we talking about here? Morels, Chanterelles, Enoki, White?

 

[rardoin]

Pictures? Whan kind of mushroom are we talking about here? Morels, Chanterelles, Enoki, White?

Don't be so pedestrian Denys....why not Psilocybe cubensis.

 

[Jackal2016]

Don't be so pedestrian Denys....why not Psilocybe cubensis.

Best to keep away from any reloading activities, etc if experiencing those I would think, lol.

 

[Ned Ludd]

Good idea. So I assume that I should be FL sizing the new brass before trimming?

Thanks for your help.

The more consistent your cartridge base-to-shoulder measurement within a single brass prep, the more consistent the cartridge overall length (COAL) measurements will be after using the Giraud trimmer, because it indexes off the shoulder as was previously mentioned.

I generally re-size virgin brass first with a FL bushing die. I use a bushing that is about .001"-.002" smaller than I would use it if were to be the sole re-sizing step. Then I open the necks back up slightly with a mandrel that is ~.0015" under bullet diameter as the final sizing step. As an example, I might use a 0.336" bushing with Lapua .308 Win Palma brass if the bushing die were the only sizing step. However, I would use something like a 0.335" bushing, and then followed that up with a 0.3065" mandrel to yield approximately .002" neck tension (interference fit). Virgin brass prepped in this manner shoots very well indeed. You still might see a couple thousandths COAL variance or so in prepped virgin brass after trimming with the Giraud, but that will typically only get better after the brass has been fire-formed.

Thanks to all. I was really surprised to see the condition that the Alpha brass in 6.5 CM came in. All of the mouths have a nasty mushroom that has to be de-burred. All part of my education process.

Doesn't the 6.5 CM Alpha brass come shipped in 100 round reloading boxes (i.e. one case per hole)? It seems like there would have to have been some pretty rough treatment during shipping for the case mouths to be damaged when the cases are packaged that way. Not impossible, obviously. I've prepped quite a bit of Alpha .308 Win brass and the case mouths were all fine. Just curious.

 

[fatelvis]

Using one of Whidden’s click adjustable lock nuts works beautifully on Giraud’s shellholders. They’re a little expensive, but they make dialing in the perfect trim length a snap!

Universal Click Adjustable Lock Ring - Whidden Gunworks

The Universal Click Adjustable Lock Ring fits both standard and co-ax presses. Please Note: The Universal Click Adjustable Lock Ring is not compatible with the Dillon Floating Toolhead.

www.whiddengunworks.com

 

[KenOath]

Could be I'm doing things wrong, but when I'm trimming new brass (Alpha, especially) to length, there seems to be quite a variation in final cut with those pieces. I'm aiming for 1.910" trim length, but on longer pieces of the Alpha brass >1.913", I end up with 1.909" to 1.907" for the final length. Those pieces at < 1.913" end up at the 1.910" that I want.

Could this have something to do with the bushing? I've checked for play with the shaft and cutter head and there seems to be none. This is an older Girard, but it has received very little use until recently.

Because the Girard indexes from shoulder other things can affect OAL of brass, you may have to look at your FL sizing in regards to dwell time, firings on brass (spring back), are you using the spring loaded case holder or cut case holder, consistent and square pressure when pushing brass into cutting blades is another consideration.. 5 thou is a considerable es difference for a premium trimmer…

 

[XTR]

But no matter your case length the necks are all the same length if you use a Giraud.

Trim after you fire once. If I'm shooting virgin brass I do a quick inside chamfer when I am loading then trim it after I resize the once fired brass. New brass from Alpha and Lapua (only ones I've measured) will have up to .005+ variation in base to datum on the shoulder. That is going to change when you shoot them the first time. If you are trimming to case OAL on new brass you are going to have a mixed bag of sizes after your first firing.

 

[PJ1]

The more consistent your cartridge base-to-shoulder measurement within a single brass prep, the more consistent the cartridge overall length (COAL) measurements will be after using the Giraud trimmer, because it indexes off the shoulder as was previously mentioned.

I generally re-size virgin brass first with a FL bushing die. I use a bushing that is about .001"-.002" smaller than I would use it if were to be the sole re-sizing step. Then I open the necks back up slightly with a mandrel that is ~.0015" under bullet diameter as the final sizing step. As an example, I might use a 0.336" bushing with Lapua .308 Win Palma brass if the bushing die were the only sizing step. However, I would use something like a 0.335" bushing, and then followed that up with a 0.3065" mandrel to yield approximately .002" neck tension (interference fit). Virgin brass prepped in this manner shoots very well indeed. You still might see a couple thousandths COAL variance or so in prepped virgin brass after trimming with the Giraud, but that will typically only get better after the brass has been fire-formed.




Doesn't the 6.5 CM Alpha brass come shipped in 100 round reloading boxes (i.e. one case per hole)? It seems like there would have to have been some pretty rough treatment during shipping for the case mouths to be damaged when the cases are packaged that way. Not impossible, obviously. I've prepped quite a bit of Alpha .308 Win brass and the case mouths were all fine. Just curious.

Yes, I had seen some good comments about Alpha brass on various forums and I ordered 300 6.5 CM. Beautifully packaged, but I have never seen mouths that had brass rolled to the point of being able to feel it and see it. I can take two pieces and slide the mouths across each other with a noticeable bump where the brass burrs contact. Never experienced this with other brass such as Lapua.

 

[KenOath]

But no matter your case length the necks are all the same length if you use a Giraud.

Providing your shoulders are set back equally, that’s dependent on fl sizing consistency, which is dependent on brass consistency eg if brass is on same firing rotation, spring back, dwell time consistency.. something is amiss if there’s 5 thou differences. Using the Girard these things are a consideration before you cut.

 

[rijndael]

Providing your shoulders are set back equally

No, regardless of shoulder setback, the Giraud will make all of the necks the same length.

Shoulder setback is only a concern if you care about brass OAL.