Case Trimming

[akinswi]

Originally Posted by Scorch

Same here. And if I do my part, it will trim brass amazingly consistently (measured with micrometer). I never trusted the Lee trimmers that go down through the neck, the web thickness on brass is very inconsistent. Are they easier to use? Absolutely! And much faster, too! But you wind up with brass of inconsistent lengths in your batch for reloading. For blasting ammo that's not a problem, but if you want accurate ammo it may be an issue.

Scorch,

My lee trimmer trims extremely accurate more accurate than my calipers can measure. Its slow it’s tedious but its dead nuts reliable.

The one down side is they are not adjustable some do not trim to recommend lengths for example 30-06 trim length we all know is recommended to be trimmed to 2.484 max is 2.494 my lee trimmer trims everything to 2.487 it does not matter if its a lapua case or a winchester case trims them to the same length everytime

another thing it does and i notice this by mistake is that the shank will deburr the flash hole on the inside of the case to some degree. I noticed this when I trimmed some sig sauer 30-06 brass had some nasty burrs gone mostly after I trimmed

[44 AMP]

The recommended trim to length is just that, a recommendation, not any kind of hard and fast rule. It's simply a length shorter than case length max, and a point chosen for convenience as much as anything else.

For most rifle rounds its 0.01" below max case length. This is a point where usually the case can be loaded several times before growing back to max length and needing to be trimmed again.

Look in a Lyman manual, and you can find cartridges where the recommended trim length is half the usual .01" or even less. particularly pistol rounds.

The recommended trim for .357, .44 Mag and .45 Colt is NOT 0.010" it is 0.005" and the trim for 9mm and .45acp is 0.003".

There is nothing magic or specially significant about trimming 0.010" its just a handy spot for rifle rounds.

guidelines...NOT rules....

[akinswi]

Originally Posted by 44 AMP

The recommended trim to length is just that, a recommendation, not any kind of hard and fast rule. It's simply a length shorter than case length max, and a point chosen for convenience as much as anything else.

For most rifle rounds its 0.01" below max case length. This is a point where usually the case can be loaded several times before growing back to max length and needing to be trimmed again.

Look in a Lyman manual, and you can find cartridges where the recommended trim length is half the usual .01" or even less. particularly pistol rounds.

The recommended trim for .357, .44 Mag and .45 Colt is NOT 0.010" it is 0.005" and the trim for 9mm and .45acp is 0.003".

There is nothing magic or specially significant about trimming 0.010" its just a handy spot for rifle rounds.

guidelines...NOT rules....

44Amp,

You are 100% correct, It took forever to get my hornady trimmer to trim the cases to 2.484 so I just stopped worrying about it

[RKG]

Originally Posted by 44 AMP

A trimmer that also works with cases that don't have shoulders?...

Touché.

But I have to admit it has been a long, long time since I've trimmed straight wall cases.

[reynolds357]

Originally Posted by akinswi

Case Trimming, Yes I know its everyone’s favorite thing to do in brass prep.

I wanted to bring this up too see if anyone else has had this issue,

I noticed if I trim based off the shoulder of the cartridge its no where near as consistent than if I use my $3.00 lee trim cutter head with a caliber specific shank and shell holder.

I have trimmed thousands of cases with the lee and honestly its so consistent its hard to believe. it trims every case with in less of half of 1 thousandths. But it takes forever. Even using a drill having to chuck every case in the shell holder is painstaking.

Even my hornady case trimmer doesnt get it as consistent as the lee. Was wondering if anyone has noticed trimming off the shoulder is not as consistent.

I do anneal my cases every time and when I resize i count to 10 before i remove the sized case to help reduce spring back

My method is unorthodox but works for me, In anything but my bench rest rifles anyway. I trim it before I size it. Use RCBS trimmer. Always within a thousandth after sized.

[44 AMP]

But I have to admit it has been a long, long time since I've trimmed straight wall cases.

I load for some tube magazine rifles and revolvers and I do trim straight wall cases, for case length (and crimp) uniformity. They don't need it often, but I do check them every load cycle. A little extra work but it makes things simpler and easier down the road in the loading cycle.

[akinswi]

I do have a Dillion RL550, anybody use or have used Dillions RT 1500 electric trimmer?

I like the idea of it being press mounted, amd that is a vaccum attachment. I would size then trim then I run the case thru a lyman m die to size the neck back.

It does however not deburr and chamfer. They do say if you run it thru the case thru the m die that it will deburr and that when you wet tumble it will smooth the case necks out

[44 AMP]

They do say if you run it thru the case thru the m die that it will deburr and that when you wet tumble it will smooth the case necks out

I don't wet tumble, so can't say what it does or doesn't do.

Can tell you the M die does not touch the outside of the case at all. So it can't de-bur the outside of the case mouth.

the two step expander will push burrs inside flat, and can be adjusted to flare the case mouth, but its not the same as a chamfer tool cutting a bevel.

[akinswi]

Originally Posted by 44 AMP

I don't wet tumble, so can't say what it does or doesn't do.

Can tell you the M die does not touch the outside of the case at all. So it can't de-bur the outside of the case mouth.

the two step expander will push burrs inside flat, and can be adjusted to flare the case mouth, but its not the same as a chamfer tool cutting a bevel.

44amp,

Thats where the Wet Tumbling and the stainless steel pins do there magic. I may just trim a few by hand and throw them in the wet tumbler and see how they fair. The RT 1500 is on my list but at $425.00, unless my volume of shooting increases can’t justify spending that much especially when we need primers and bullets

I love my RCBS VLD deburr tool on my RCBS prepstation , but having the M die pretty much made that obselete. I just chamfer and deburr by habit now.

but the M die behind my redding competition seater die was one of the best purchases I have made

[44 AMP]

I got an "M" die with every set of Lyman pistol dies I ever bought. The "M" die body is just Lyman's name for an open die body, and in die sets, it comes with which ever expander stem is correct for that caliber. The die bodies are all the same, the only difference is which expander is in it.

Having "M" dies in my .38/357, .44Spl/Mag, and .45ACP Lyman die sets already, all I needed to load cast bullets in .30 cal rifles was the .30 cal expander stem.

Bought one decades ago. Haven't used it in nearly as long, no idea where it is now...

[armoredman]

Years ago I started trimming with the big round ball Lee hand trimmer, and my hands ached after 20 cases. I upgraded to a Lee Zip Trim, which was much faster and easier on the hands, by far. Years after that I found a Forster trimmer in a pawn shop for $5 - with pilot and collet! Grabbed that one fast.
But I like loading lots of .223 when I can, and NATO brass kills me with the crimped primer pocket, so having to trim and then put in the RCBS swaging die was a slight pain. So, being in FAR better financial circumstances than I was, I ordered a Frankford Arsenal Platinum trimmer with the optional primer reamer setup. After swapping a bad unit back to the company for a new one, ( OUTSTANDING customer service from Frankford Arsenal!), I cannot believe I got along without this ting. Yes, it trims off the shoulder, but I am not loading precision ammo, just basic blasting/training stuff. For precision I'll use the Forster. However, the FA Platinum seems to hold trim length quite well.
Still have the Zip Trim and the original hand trimmer still...

[akinswi]

armoredman,

Lol I thought adding the ball too the cutter head was an upgrade.

[markr6754]

Originally Posted by 44 AMP

A trimmer that also works with cases that don't have shoulders?...

They are costly...and moreso these days but the Hornady Lock-N-Load Power Case Prep Center should work for any type of case. I recently acquired a used one for about half price, but I haven't used it yet...preparing to trim some 224 Valkyrie cases shortly.

[Unclenick]

Originally Posted by 44 AMP

A trimmer that also works with cases that don't have shoulders?...

The Giraud has case holders for both rimmed and rimless straight cases (the pistol magnums and 30 Carbine) but I don't have any of them, so I can't say how they work. I've never needed to trim enough of those cases at one time to justify the investment. I should call and ask how they work, though.

[akinswi]

Originally Posted by Unclenick

The Giraud has case holders for both rimmed and rimless straight cases (the pistol magnums and 30 Carbine) but I don't have any of them, so I can't say how they work. I've never needed to trim enough of those cases at one time to justify the investment. I should call and ask how they work, though.

Nick,

https://www.giraudtool.com/giraud-power-trimmer.html

at the bottom of the page of the link above you can see the shell holder setup for the straight wall cartridges and looks like you can adjust the trim length with the locking ring and the case body die

[Unclenick]

Thanks. I missed looking down that far. It appears they are registering on the shell holder deck. That will transfer the location of the front of the rim to the deck thickness, so they are still registering on the headspace determining surface. That will be a lot slower to use, with the extra step of putting the case in the shell holder and tightening it. It will also mean that if you are trimming for consistent roll crimps, you will want to sort your cases by rim thickness for trimming and adjust accordingly.

[armoredman]

Originally Posted by akinswi

armoredman,

Lol I thought adding the ball too the cutter head was an upgrade.

It was - the first one had a simple handle - the ball actually made it better, and Great Scott, that two-in-one chamber/deburr tool!

[Unclenick]

I'm not sure those burr-ridden tools are actually greater than Scott was. They work in a pinch, but when I do a manual chamfer and deburr, I want' something with actual cutting teeth on it.

[armoredman]

Exactly - forgot to use the sarcasm font. I still have it somewhere, horrific tool.