Giraud vs. Henderson Case Trimmer

[Ccrider]

If you take a case that is 1.157 in length and trim it so that it measures 1.500" from the case head to the case mouth using either a Giraud or a Wilson that case is still 1.50 inches. The .007" of brass that was removed was removed from the case mouth regardless of which trimmer was used. The distance from the shoulder datum to the case mouth will be the same on each assuming both were sized correctly and had the same amount of springback.

Like I said earlier I am not putting the tools down, they are good tools. I have too much invested in my five Wilsons to ever change over but that is just me.

The way to get the true answer would be to set the case length the same in each and then see if either trimmer takes more off the cases trimmed by the other.
Or, take two cases the same OAL, bump the shoulder back further on one, trim them both. You will see that they will not be the same length after trimming. I don’t think you will end up with brass the same length.

 

[PracticalTactical]

The same guy is on sniper's hide telling people if you don't use a vibratory scale capable of 0.002 gr accuracy, you suck and can't load a low ES.

Guys like Tyler here need to learn to read and understand the actual words and learn to tune out the scary little voices inside his head.

Tyler is misrepresenting what I said.

When he cant debate something based on facts, he attacks the person he disagrees with. I think they call that Scarecrow.

 

[Trevor60]

If you take a case that is 1.157 in length and trim it so that it measures 1.500" from the case head to the case mouth using either a Giraud or a Wilson that case is still 1.50 inches. The .007" of brass that was removed was removed from the case mouth regardless of which trimmer was used. The distance from the shoulder datum to the case mouth will be the same on each assuming both were sized correctly and had the same amount of springback.

Like I said earlier I am not putting the tools down, they are good tools. I have too much invested in my five Wilsons to ever change over but that is just me.

Sometimes a picture better explains the discussion, here is a 6mm BRX and BR case both are the same OAL and a comparions of the two different trimmers




Henderson trims based on OAL setting up the trimmer to cut 1.560 you would get the same OAL but very different case dimensions
Giraud trims based off the shoulder so you would get the same shoulder neck dimensions but very different OAL.

As always the question is how much variation in shoulder bump in needed to impact or ES/SD group size.

I watched the video TWICE. what i can't figure out is why the Henderson produced such better ES/SD numbers. Does the little mandrel holding the case (burnish, polish, smooth out or lube) the inside of the case mouth to produce better seating numbers. OR does the Giraud trimmer need adjusting. the chamfer angle is not allot different between the two Henderson 14o vs Giraud 15o.

Cheers
Trevor

 

[Straightshooter1]

I watched the video TWICE. what i can't figure out is why the Henderson produced such better ES/SD numbers. Does the little mandrel holding the case (burnish, polish, smooth out or lube) the inside of the case mouth to produce better seating numbers. OR does the Giraud trimmer need adjusting. the chamfer angle is not allot different between the two Henderson 14o vs Giraud 15o.

I think the graphs pretty much says why Henderson produced the better ES/SD numbers. But . . . to really be able to come to any conclusion, one needs to repeat the test to see if the results are the same. Going through a test just one time just doesn't confirm anything. With that said, when I look at the graphs and focus on the beginning of the seating), it appears to me that the Giraud cutter may not be cutting as smooth as the cutter in the Henderson. When a cutter is not cutting smoothly, I'd expect to see a graph like the one I see with the Giraud. And yeah, it doesn't seem to me like that little difference in cutting angle, for the angle alone, would make that much difference. It'd be interesting to take a bore scope and take a close look at the chamfers after trimming and compare.

 

[F Class John]

I appreciate the conversation this post sparked, but please remember I was very open in the video about the fact that this was a single test and wasn't the be all end all answer. It was simply a test between my current Giraud settings vs. how the Henderson was sent to me. It represented one day, one trimming and one day of shooting. Neither unit is a slouch and I agree with others that I could probably manipulate the Giraud until it produced a mouth that gave similar results on the AMP Press to the Henderson. In fact if you watch my other AMP Press videos you'll see that with the Giraud, I was able to ever so lightly (and also by not chamfering either) produce a similar curve that the Henderson shows but I also tested the opposite. The deeper the chamfer with the Giraud, the more abrupt the spike on seating. All I can say is that I'm getting a great chamfer with the Henderson AND no spike but does that spike matter on paper? Hard to say yet, and there's certainly plenty of guys including myself who have shot for years getting tiny holes with the Giraud who are probably getting that spike even if they can't see it when using a regular press.

My only other testing thus far with the Henderson was blowing off some rounds I trimmed when I got it with the result below. I have two new barrels going into service today and everything going forward right now will be with the Henderson so I'll keep you posted.

 

[Trevor60]

I think the graphs pretty much says why Henderson produced the better ES/SD numbers. But . . .

The graph is telling it show there a clear spike using the Giraud but I referenced the miner angle differences between the two trimmers. John said he had a picture to share in the video. maybe he can share it here.

Would a 13o cutter produce even better numbers or does the aligning mandrel (burnish, polish, smooth out or lube) the inside of he case. He did have one case that did not fit over the mandrel so the tolerances are tight.

Cheers
Trevor

 

[Straightshooter1]

All I can say is that I'm getting a great chamfer with the Henderson AND no spike but does that spike matter on paper? Hard to say yet, and there's certainly plenty of guys including myself who have shot for years getting tiny holes with the Giraud who are probably getting that spike even if they can't see it when using a regular press.

And that's a good question and a good point about the number of shooters doing well with the Giraud and not knowing about such spikes they might have from it.

BTW: like so many other here, I very much appreciate the effort you go to in providing these kinds of comparisons. No doubt in my mind that it's a significant contribution to knowledge for many with interest in precision reloading.

Would a 13o cutter produce even better numbers or does the aligning mandrel (burnish, polish, smooth out or lube) the inside of he case. He did have one case that did not fit over the mandrel so the tolerances are tight.

It doesn't seem to me that a 13° cutter would make much difference with boat tail bullets. But your question about the burnishing the inside of the neck is a good and I have little doubt that it has some effect; just how much effect. . . ¯\_(ツ)_/¯

 

[Papa Charlie]

I would have like to see this test done with a new cutter in the Giraud. Cutters don't last forever and you indicated you have done thousands of cases on the Giraud's current cutter. That alone could have caused the issue that we are seeing.

 

[F Class John]

I would have like to see this test done with a new cutter in the Giraud. Cutters don't last forever and you indicated you have done thousands of cases on the Giraud's current cutter. That alone could have caused the issue that we are seeing.

And that’s totally fair but I can tell you that I just recently rotated the cutter to a new cutting side. So it has not had very many on it.

 

[Papa Charlie]

And that’s totally fair but I can tell you that I just recently rotated the cutter to a new cutting side. So it has not had very many on it.

I must have misunderstood you in the video. You also indicated that you periodically pull the cutter out to clean under it. Can you be sure that it always goes back in in the same orientation? You probably have it marked for this. I also wonder how the position of the cutter on the Giraud is set. It maybe that it isn't aligned for the best outcome considering we are working on a very small ridge.

It would be interesting as stated above to see a borescope enlarged image of the two chamfers just to see if there is a difference.

Thanks for sharing this John. A whole lot of remote speculation going on here. A perfect application of the force measuring tool.

 

[F Class John]

I tried using a borescope and honestly it was really tough for me to get a clear picture. This is the photo that was supposed to go in the video and after somebody in the comments mentioned it I realized I forgot to put it in so I was going to do a follow up video at another time. The Giraud is on the left and the Henderson is on the right and as many people have said there are infinite ways to adjust the cutter head to the exact way you want it to look. Again this was just a point in time with how I was using my Giraud versus how the Henderson arrived at my door.

 

[JimSC]

Sometimes a picture better explains the discussion, here is a 6mm BRX and BR case both are the same OAL and a comparions of the two different trimmers


View attachment 1293971

Henderson trims based on OAL setting up the trimmer to cut 1.560 you would get the same OAL but very different case dimensions


Cheers
Trevor

Maybe I am just dense but if I had 2 cases one a 6BRX and one a 6BR and they were both 1.565 OAL and I trimmed both to 1.560 OAL the cutter would be removing .005 of brass from the mouth of the case regardless of what point on the case I was indexing off of. The only case dimension that would be altered is the distance from the case head to the case mouth.

edit nevermind. I see what you are getting at. If you have unevenly sized cases the distance from the case mouth to the beginning of the shoulder would be different. As another poster pointed out that would be a sizing problem, not a trimming problem. Maybe I should amend my statement to "with properly sized and annealed cases it would make no difference where you index from".

That said I would think anyone who cares enough to spend several hundred dollars for a trimmer would be sizing his or her cases properly before trimming

 

[Papa Charlie]

Thanks for sharing the image John, pretty darn good image.

I can see two things that stand out;

1) The Giraud has a much deeper rake on the chamfer than the the Henderson, oddly, my first impression would be that the Giraud would have less trouble starting the seating.

2) The Giraud has a very sharp edge that is created between the chamfer and the debur while the Henderson has a flat transition on the mouth of the case. Could be the bullet is catching this sharp edge initially causing the initial resistance. Once it is past that point, if I remember correctly, I think both produced about the same amount of pressure.

 

[Dave Way]

All I know is the Giraud works for me. Dave

 

[Papa Charlie]

No doubt that they are both very fine tools. I wish I had the resources to have the Giraud.

I just love to analyze, it is my manufacturing/engineering background.

 

[JimSC]

All I know is the Giraud works for me. Dave

View attachment 1294174

View attachment 1294176

Probably a bit of shooting and reloading skill involved here also. If all it took to shoot like you was to use a certain brand trimmer I would be ordering 5 this afternoon.

 

[Big_Daddy]

1- Because I can
2- Speed. I can trim/ deburr 100 rounds in about 6 minutes or less with a Giruad
3- So you’ll have something to complain about

Exactly!!!
I own 3 Girauds and love them.
Why do I own 3? BECAUSE I CAN and I leave 2 setup for dedicated calibers. The 3rd is changed to whatever "oddballs" I may be doing.
I don't understand why people feel the need to look down on people's decisions to spend $$$ on the toys they like and enjoy using. I really could care less if someone decides to use a hand file, a rock or some other method to "trim" their cases. Do what you like and leave it at that.
The discussion was about 2 different trimmers NOT why anyone thinks I or someone else needs one....PERIOD

 

[kindabitey]

Exactly!!!
I own 3 Girauds and love them.
Why do I own 3? BECAUSE I CAN and I leave 2 setup for dedicated calibers. The 3rd is changed to whatever "oddballs" I may be doing.
I don't understand why people feel the need to look down on people's decisions to spend $$$ on the toys they like and enjoy using. I really could care less if someone decides to use a hand file, a rock or some other method to "trim" their cases. Do what you like and leave it at that.
The discussion was about 2 different trimmers NOT why anyone thinks I or someone else needs one....PERIOD

I don’t have room for 3

 

[INTJ]

To channel @Dave Way, the Henderson works fine for me. The pic is 3.855" at 1000 yds. However, my group was only the second best that day was beaten by @GlennK by better than an inch, setting a new IBS record. Maybe Glenn uses a Giraud.......



However, I don't think trimming is that important so either trimmer works fine. That said, a trimmer that indexes of the shoulder, like the Giraud, is theoretically more accurate as @BoydAllen has been saying.

That is because upon firing, the case expands to fill the chamber. I think that happens before the neck expands off the bullet. This means the critical dimension is the measurement from the shoulder to the case mouth. And as perfect as some of like to load for our competition rifles, there will always be some variation in shoulder bump.....even when we have convinced ourselves that we are consistently measuring to .0005" with our Mitituyo calipers.

 

[BoydAllen]

Nice group, really nice. Tell us about the rifle.