Which is best...one that registers off the shoulder or one that is just based on overall length? Power or manual? What's an acceptable variance? Do any give you the exact same neck length? Can't quite figure if the shoulder variety does this or not...brain is a little fuzzy this morning! What do you folks use and why?
Case Trimmers?
- Thread starter C Valentine
- Start date
jonbearman
I live in new york state,how unfortunate !
I have 2 graceys that's et up to do .308 and .223 the rest get done on a Wilson as it is the most accurate trimmer on the market. It holds the case body and when you are done the neck face is square. Then you have to chamfer which gets done with a drill adaptor. I use a vld type for the inside and a normal Wilson trimmer to do the outside,labor intensive for sure . If you are only doing 50-100 at a time it is fine. I also use an adaptor to run the Wilson with a drill. The graceys are ok but I think the Giraud is the winner when is comes to perfection.
Turbulent Turtle
F-TR competitor
ShootDots said:
That's what I use every time after resizing my cases. I used to loathe trimming, even with a powered device, but with the Giraud I can accurately trim, chamfer and deburr 100 cases in just a few minutes.
ETA: The Giraud indexes off the shoulder so you must resize the case first. After setting it up, I get consistency of +/- .001. It is important to use the same hand pressure for every case you trim; let the device do its job.
Well the Giraud is not an option...too many other things I need that take priority. Like some bushing dies. 
Then a .308 and all that goes with it... Damn this sport is expensive. Combine that with addictive and it almost spells bankruptcy! LOL I have a WFT but am not totally happy with it. (I suspect it may be more my technique than the tool.)
Then a .308 and all that goes with it... Damn this sport is expensive. Combine that with addictive and it almost spells bankruptcy! LOL I have a WFT but am not totally happy with it. (I suspect it may be more my technique than the tool.)Turbulent Turtle
F-TR competitor
You might want to look at the other trimmer that Giraud offers. It does the same as the big trimmer, but you use it with your own drill or motor. It's $90 and it's called the Tri-way trimmer.
http://www.giraudtool.com/Tri%20Way%20Trimmer.htm
http://www.giraudtool.com/Tri%20Way%20Trimmer.htm
Both Forster and RCBS make three way cutter heads for their respective trimmers. Cutters are high speed steel which would need to be sharpened eventually. The only problem I ever had with my Forster manual was that the set screws holding the depth-of-cut collar would loosen. I would be hesitant to use that type of manual trimmer again. I think a good alternative would be Giraud's new Tri-cutter. Especially if you could mount it in a good drill press. Wilson's are great but I am not really sure you need to be that precise unless you have a tight neck, short throat chamber. Labor intensive, as some one else has already stated. My Gracey developed some lateral movement in the cutter shaft that can cause some variation in lengths.
Just food for thought.
Just food for thought.
PDS
Gold $$ Contributor
I copied this from the calguns.net site. It does a good job of answering the original question from xhuntress.
There's trimming to length and trimming to length. You could trim your cases to the same OAL, but not have the same length on the neck, which could cause a difference in neck tension from round to round.
I'll let an expert explain better. The following is from Doug Giraud, who makes the famed Giraud Trimmer which is arguably the best one out there.
When a trimmer grips the case rim, like the RCBS unit, it will control the distance from the rim to the case mouth to an exact length. The downside is that there is no guarantee that the brass has been resized, or resized properly to any specific given dimension. That type of trimmer, as well as the Lee, Forester, or any lathe type is that they don't care about what is between the rim and case mouth. Your brass could be undersized, oversized, some combination of both, and/or not resized at all.
With the Giraud and the Gracey, the case holders are indexing the cases off the shoulder of the case. These trimmers will trim the brass from the shoulder forward to a given dimension, but not necessarily the exact same dimension from case to case if the headspace dimensions vary. The headspace dimension is the distance from the case rim to the midpoint on the case shoulder. This will control how tightly or loosely the case will fit in the rifle chamber. If the headspace is looser than it should be, the case will be sloppy in the chamber, if it is too long, you may have troubles closing the bolt on a loaded round.
Theoretically, if the headspace was way short and the case was sloppy loose, even though the distance from the rim to the case mouth was right on call for SAAMI dimensions, the case could slide forward enough to allow the case mouth to get restricted by the end of the chamber and cause the typical problems associated with cases that are too long.
With the Giraud and Gracey style trimmers, the distance from the shoulder to the mouth is exactly the same from case to case and there is no way the mouth could be restricted by the end of the chamber if the case was trimmed properly. The shoulder of the case would prevent the case from going forward any more and causing problems. Where some people have a problem with these types of trimmers is that the overall length can vary by however much your headspace dimension varies. But that is a function of your ability to consistently resize cases, not the trimmer. The problem is that most everybody measures only the distance from the rim to the case mouth and sees some variation. They don't usually take the time to get a case gauge, like a Stoney Point comparator, and measure the distance from the rim to the shoulder and see that the variation is there, not from the shoulder forward to the case mouth.
Reloaders who have been making match grade ammo for competition or such usually have learned this the hard way and take more care when resizing brass to make the headspace more uniform. With brass that is consistently resized, the overall length from a Giraud or Gracey trimmer will usually be as uniform as your ability to control that headspace dimension.
Now all the trimmers have the ability to trim a .223 case to 1.750" on a regular basis. But if you don't know that the headspace on the case is .020" short and you only measure the rim to case mouth dimension, you don't know that your case is sliding .020" further into the chamber than you thought and may create problems. With the Giraud and Gracey trimmers, the case holders will typically not work well unless the brass has been resized, so there is one check you can make easily. Does the case go into and out of the case holder easily? If not, check it out. The you can check the headspace of a few cases and see if they are consistent. If they are, you can set the trimmer to remove enough material to know that the case will function properly, and the headspace will prevent the case from sliding around inside the chamber. And lastly, with proper headspace, you stand a better chance of getting accurate loads and longer life from your brass than if the headspace was excessive or random.
Sorry for being so long winded, but I am an engineer. And we all know what that means, I have low earning potential and poor social graces.
HTH,
Doug Giraud
There's trimming to length and trimming to length. You could trim your cases to the same OAL, but not have the same length on the neck, which could cause a difference in neck tension from round to round.
I'll let an expert explain better. The following is from Doug Giraud, who makes the famed Giraud Trimmer which is arguably the best one out there.
When a trimmer grips the case rim, like the RCBS unit, it will control the distance from the rim to the case mouth to an exact length. The downside is that there is no guarantee that the brass has been resized, or resized properly to any specific given dimension. That type of trimmer, as well as the Lee, Forester, or any lathe type is that they don't care about what is between the rim and case mouth. Your brass could be undersized, oversized, some combination of both, and/or not resized at all.
With the Giraud and the Gracey, the case holders are indexing the cases off the shoulder of the case. These trimmers will trim the brass from the shoulder forward to a given dimension, but not necessarily the exact same dimension from case to case if the headspace dimensions vary. The headspace dimension is the distance from the case rim to the midpoint on the case shoulder. This will control how tightly or loosely the case will fit in the rifle chamber. If the headspace is looser than it should be, the case will be sloppy in the chamber, if it is too long, you may have troubles closing the bolt on a loaded round.
Theoretically, if the headspace was way short and the case was sloppy loose, even though the distance from the rim to the case mouth was right on call for SAAMI dimensions, the case could slide forward enough to allow the case mouth to get restricted by the end of the chamber and cause the typical problems associated with cases that are too long.
With the Giraud and Gracey style trimmers, the distance from the shoulder to the mouth is exactly the same from case to case and there is no way the mouth could be restricted by the end of the chamber if the case was trimmed properly. The shoulder of the case would prevent the case from going forward any more and causing problems. Where some people have a problem with these types of trimmers is that the overall length can vary by however much your headspace dimension varies. But that is a function of your ability to consistently resize cases, not the trimmer. The problem is that most everybody measures only the distance from the rim to the case mouth and sees some variation. They don't usually take the time to get a case gauge, like a Stoney Point comparator, and measure the distance from the rim to the shoulder and see that the variation is there, not from the shoulder forward to the case mouth.
Reloaders who have been making match grade ammo for competition or such usually have learned this the hard way and take more care when resizing brass to make the headspace more uniform. With brass that is consistently resized, the overall length from a Giraud or Gracey trimmer will usually be as uniform as your ability to control that headspace dimension.
Now all the trimmers have the ability to trim a .223 case to 1.750" on a regular basis. But if you don't know that the headspace on the case is .020" short and you only measure the rim to case mouth dimension, you don't know that your case is sliding .020" further into the chamber than you thought and may create problems. With the Giraud and Gracey trimmers, the case holders will typically not work well unless the brass has been resized, so there is one check you can make easily. Does the case go into and out of the case holder easily? If not, check it out. The you can check the headspace of a few cases and see if they are consistent. If they are, you can set the trimmer to remove enough material to know that the case will function properly, and the headspace will prevent the case from sliding around inside the chamber. And lastly, with proper headspace, you stand a better chance of getting accurate loads and longer life from your brass than if the headspace was excessive or random.
Sorry for being so long winded, but I am an engineer. And we all know what that means, I have low earning potential and poor social graces.
HTH,
Doug Giraud
Excellent! Thanks for posting that article. Logic was telling me that the shoulder was the place to measure from. It also told me that I needed to have a consistent amount of neck surrounding the bearing surface of the bullet in order to get consistent results. But everyone seemed to always measure COL, which, if all of your shoulders are the same would be okay. Unfortunately, I think I need to work on my resizing!
Most of the new un fired cases I have checked measure 3 thou below the zero on my Mic. After fire forming, loading to a jam, most have grown about a thou, some more and some not at all, so I am not really sure where I should be sizing them, or if I should be even worrying about a 2 or 3 thou difference at this point. I am assuming the shoulder will move out a bit with each firing, but how do I know what the final proper length is to set my resizing die so that I eventually end up with all of them the same so that when I trim them, all the necks are the same length? I am just learning about FL sizing, so it's all a bit confusing.
Thanks though...I have answers to my original questions! And as always, one question inevitably leads to others.
Most of the new un fired cases I have checked measure 3 thou below the zero on my Mic. After fire forming, loading to a jam, most have grown about a thou, some more and some not at all, so I am not really sure where I should be sizing them, or if I should be even worrying about a 2 or 3 thou difference at this point. I am assuming the shoulder will move out a bit with each firing, but how do I know what the final proper length is to set my resizing die so that I eventually end up with all of them the same so that when I trim them, all the necks are the same length? I am just learning about FL sizing, so it's all a bit confusing.
Thanks though...I have answers to my original questions! And as always, one question inevitably leads to others.
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.
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.