Case trimming in the lathe

[yovinny]

I've noticed a few references to people using laths for case trimming.
I'd like to know, what kind of chucking and tooling are you using or have found best ?

I've tried 2 different 3 jaw scroll chucks without much joy.
I've tried a 3 jaw scroll with soft jaws and bored them to fit a particular case, but while it worked better, it has limited interchangeability for other calibers.
I was thinking of using my collet chuck and getting an blank 5C collet to bore with steps (like a forster case trimmer 'chuck') but that would seem to provide very limited case support without also using a piloted type trimmer.

Any info and ideas appreciated, TIA.

Cheers, YV

[country gent]

I think if I was going to use a lathe for trimming small amounts I would set the cutter in the spindle and make a case holder /collet for the carriage. this would save startig and stoping the spindle for every case. For reformed brass where alot needs to come of fixture for a collet fixture to hold on the body and a very thin cut off blade in the carraige to slice of the excess. A cuttoff blade .030 wide or thinner would make short work of trimming 1/4" off . A set of soft faws can be drilled and taped to loch a brass or aluminu jaw set in place. Bore the bushing to hold case and split into 3 ecual sections bolt or glue onto jaws.

[Three44s]

I am no machinist however if I was set on such an endeavor, I'd take a look at the Wilson Tool and Gauge stuff for a starting point.

They make a case holder for specific cartridges and cartridge families and for specific conditions.

Whether it would make economic sense to buy their holder instead of building your own , you can determine after you price them.

(I use several of their holders along with their trimmer body for my more precise cartridge combos, and a Lyman universal for general trimming, if I got more heavy cutting a Harbor Freight mini chop saw would get bought)

Best regards and good shooting!

Three 44s

[bangerjim]

Lathe trimming is very time consuming and a LOT of busy work. I have 5 metal lathes and use the LEE QuckTrim in a single stage press dedicated to trimming instead. Fast and accurate. Trims and chamfers with just a few turns of the handle!

I made a horizontal trimmer last year and have not even used it since I bought the Lee and all the adaptors for the sizes I trim.

I could not imagine spending all that time tightening and untightening a lathe chuck and cranking the carriage around just to trim some brass. Then you have to chamfer it! There are better, much faster, more accurate ways to do it.

banger

[rbuck351]

I use the Lee trimmer with the case holder in the lathe chuck. Once trimmed I deburr while still spinning then shove a empty 12ga shell filled with steel wool on the end of the case and all done. Just takes a few seconds to stick a new case in the holder and repeat.

[yovinny]

Lathe trimming is very time consuming and a LOT of busy work.
I could not imagine spending all that time tightening and untightening a lathe chuck and cranking the carriage around just to trim some brass

Well, thats been pretty much my experience also, besides finding no really good way to hold the cases.

Using the Lee trimmer holder would probably be faster, but even at that, I really dont see how it could be better, faster or easier than just using it set-up in the drill press.

I really want to hear from one of these guys that are always claiming trimming in the lathe is just the end-all bee's knees greatest thing since sliced bread :neutral:

[GRUMPA]

Even though I have a lathe, that's something that just isn't fast enough, nor accurate enough.

I use custom 3-way trimmers, which pretty much does everything all in 1 shot. Most of the time it takes me longer to put the case in than it does to trim, and I don't care if I'm taking off .100 or more, it goes really fast....

[rbuck351]

For those using a drill press, just think of the lathe as a horizontal drill press and you can see why it's just as fast. You can use a drill chuck in either end or both if you want. I use the Lee case holder in the lathe chuck and the just stuff the lee hand held pilot cutter in the case then deburr and polish all in about 15-20 seconds per case. The Lee case trimmer/pilots are fast and accurate and the case holder is very quick as well, it takes 3-4 seconds to change a case. If I'm forming a bunch of cases that need a lot of length removed say 1/4" or even more, I make rod that fit's the inside of the neck sharpened like a screwdriver so it bites slightly on the inside base of the case, run the live center in the primer pocket and with the cross feed carriage and tool set and locked just part them off for final length trim after sizing. I have a Sears 6x18 benchtop lathe that lives on one of my loading benches. It also makes GH&I dies Star sizer dies, Swag-o-matic dies. GC making dies and a bunch of other stuff. It's a very versatile case trimmer.

[Lead Fred]

151624

Been using an LE Wilson case lathe since 1961

A might cheaper than a machine shop

[bangerjim]

With my press-held Lee trimmer, I can trim AND chamfer (inside and out) a case in 5-8 seconds.....lots faster than any lathe set-up.

At 20 seconds to ONLY trim, that is almost 3 hours to trim 500 cases! And you still have to chamfer them.

My philosophy has always been: use the correct tool and for the purpose it was designed for.
Guess that is why I have ever tool made by man.....and many of my own design.

But do whatever floats your boat.

banger

[Frank46]

I used to use the wilson but now just the lee cutter and lock stud. Just stick in a variable speed drill, trim and chamfer.Frank

[sdcitizen]

I use the lee cutter with appropriate case guage mounted in the headstock, and handle the cases by hand. It only works for primed cases, as the pin on the end of the guage has been shortened to set length off the center of a primer anvil. It is very fast though, can do a 3 gallon bucket of 233 in less that an hour, i would guessan average would be 4 seconds per case, maybe 3 seconds after doing several hundred.

[eagle27]

Many years ago since I trimmed a bunch of 45LC cases down to fit my 455 Webley but I used a big old flat belt driven lathe to do the job. Turned up a spindle to hold in the 3 jaw chuck over which cases would snuggly slip bottoming on the inside web head and held on the spindle using a small tail stock live drive in the primer pocket. Set up a sharp parting tool in the spindle at the right case length and went to it. Didn't take long to trim a hundred or so new cases and I also thinned the rims using exactly the same system to hold the cases but did this as a separate step after setting up another tool in the turret (was not a multi tool turret).

[rondog]

Giraud here, FTW.

[pdgh59]

Has anyone had success in trimming 24 gauge brass down in a lathe to use in a 577 Snider? If so how did you hold the case?

[BigEyeBob]

I use the Lee trimmer with the case holder in the lathe chuck. Once trimmed I deburr while still spinning then shove a empty 12ga shell filled with steel wool on the end of the case and all done. Just takes a few seconds to stick a new case in the holder and repeat.

Thats what I do , and for my odd calibre cases that Lee dont make length gauges for I make my own length gauges ie: 300 Sherwood , 300 Rook etc.
Its pretty fast and takes little time to trim 100 cases

[yovinny]

Giraud here, FTW.

LOL,,,
Yea,, I have a Gracy on the short list, just for rifle calibers I load in bulk. Especially since I learned it also readily uses the better Giraud blades, so total cost even with a Giraud blade is still a C note cheaper for basically the same 'electric pencil sharpener' machine.

I can see using the lathe for specialized jobs, like thinning rims, etc. but otherwise it makes little sense to me. I tried it all sorts of ways without any joy and always went back to the Forster case trimmer and a battery drill...Which I have two of with a ton of pilots, that are paid for and I'll still use for calibers I dont shoot as much.

Cheers, YV

[jmorris]

Depends on the case your trying to trim but soft jaws could be machined to hold the taper with some you could get away with a collet.

I have used a mill before again you can make any shape jaws you want.

not very practical though lots of better and faster ways to do the job.


https://www.youtube.com/watch?v=LaBON6F1LlQ

[Eddie2002]

I've been using a Unimat mini lathe for trimming cases. One of the biggest problems was the fact the 3 jawed chuck would dig into the case and score it up. It would happen with tapered cases like 308 Nato or 30-06. I ended up wrapping the base of the case with a strip of paper about a 1/2 inch wide along with some clear packing tape. By folding the paper over on it's self once or twice along the leading edge I was able to compensate for the case taper. I ended up with a paper/tape sleeve that would be tight on the base of the case but could be slid onto the case from the top. It also protected the cases from scratches or damage. The sleeve also works for rimmed cases, I just make it thicker without a taper.
To trim the cases I use a carbide cutter set a little at an angle and have a stop on the feed bar. It's really accurate and can trim about 2 cases per minute.
I think the reason it works so well is because of it's small size, I don't think trimming cases on a larger lathe wouldn't be feasable.

[Three44s]

I bought a carbide cutter for my Lyman universal trimmer ........ I squalled at the (then) $42 price for it but have never looked back ...... it's fast because it always sharp ........ unlike steel cutters which periodically need resharpening.

I tried a drill press trimmer setup ..... and found it's not accurate to length ........ even my Lyman univ. is not super accurate .........

So when it's time to split hairs, it's the Wilson then.

I bought a used RCBS trimmer with the intention of setting with their 3 way cutter head on often used cailbers but have not gotten the rest of the tooling yet.

Best regards

Three 44s

[country gent]

Several things speed up using the lathe for trimming. mount the cutter in the headstock ( this allows you to not have to stop and start the lathe spindle every time). A fixture to hold brass in the tail stock or carriage. with compound set 90* (parallel to lathe bed. and cases held in a fixture this would provide fine adjustment for tje cuts length. A stop on the lathe bed for carriage to butt against is needed. The fixture needs to be a quick release clamp. think a brass rod bored for the case split and hinged you can open it set case in and pinch closed with fingers wheile cutting. Set up would require indicating the case into dead center then not touching anything other than carriage feed wheel and compound for fine adjustments. An small angle plate or alloris tool block could be set up to do this. Making the tooling would be an investment in time and material though. For most trimming the simple cutters work well. a drill press is cheaper and eaasier to set up. ( a cheap bench top drill press can be dedicated and left set up even)

[rbuck351]

Actually what I said was 15/20 seconds for trim, deburr inside and out and polish the case mouth but read it anyway you want. And that includes mounting and dismounting the case.
Banger ,you have me curious. What kind of Lee trimmer are you using and how do you hold the case to spin it? Could you describe your process a bit better?

[Idz]

To trim down 24 ga brass for forming into 577/450 Martini-Henry I use my 3-jaw chuck on my 9x20 import lathe. The case head drops nicely into one of the notches in the jaws so I can gently tighten on the OD. Then take very light cuts to trim to length.

[Tackleberry41]

I think with the 577 snyder, it would be faster to cut most of it off with a dremel, then the last little bit with a trimmer. I know an issue that comes up is finding a trimmer the 24ga will fit in. It wont fit in my universal head RCBS trimmer. I got lucky and bought the lee hand trimmers for my 577/450 before they stopped making them. Thats what I do, cut most of it with a dremel, then the last little bit with the trimmer.

I have a lathe, and do not see how without special tooling it could be faster at trimming. I have trimmed a case here or there, usually something like turning a rim down, and its not fast. But I am not willing to spend a bunch of time messing with modifying a chuck or making some tool to do it. I can clamp my old RCBS trimmer down and away you go. Or the Lee trimmers for some stuff.

[bangerjim]

Actually what I said was 15/20 seconds for trim, deburr inside and out and polish the case mouth but read it anyway you want. And that includes mounting and dismounting the case.
Banger ,you have me curious. What kind of Lee trimmer are you using and how do you hold the case to spin it? Could you describe your process a bit better?

http://www.midwayusa.com/product/717013/lee-deluxe-quick-trim-case-trimmer

Uses standard shell holders in your press. Just buy the die for the cal you are trimming.

You do NOT spin the case!!!!! The die firmly holds the case. You spin the cutter blades by turning the crank on top. I have 9 of the dies. Fast and efficient. And you get a little arm exercise in the process. I just dedicated a simple $25 extra Lee press for this purpose. Perfect clean trim + double chamfered in just a few turns of the handle. If one is uber-lazy, they even sell a power adaptor for a drill. Why on earth anyone would need that is beyond me. Holding a drill in the air is a pain in the.........ARM. 6 or 8 turns of the big crank know and all is done.

banger

[rbuck351]

Banger
That is really slick. Where do you buy trimmer dies for 25/20, 32/20,358N,350Rem, 7.62x25,7.62x54R,35Rem,300H&H,22H,30Rem?

[Latheman]

Ive been thinking about doing this myself. I have access to a Johnford twelve tool turret cnc lathe and it uses quick change collets. The way I would do it is set a stop in the spindle use a 3/8 collet for 223/5.56 cases chuck pressure 80 psi. Use a RH turn tool to hit the 1.75 oal than set up the deburr tool in a drill collet and deburr. run all the cases one side reset the stop in the chuck than lightly chamfer the military crimps out. I think about doing this every time im trimming hundreds of .223 cases. Total run time about 15 to 20 seconds side 1 and 10 seconds side two. 15 minutes to write the program. I know most people cant do this but thats why I love being a machinist.

[garandsrus]

A Gracey or Giraud trimmer is a much faster way to go than using a lathe. 2-5 seconds per case to trim, chamfer, and debut the case.

[EDG]

Many of the methods suggested will not trim ALL case designs but an engine/tool room lathe can be used to trim almost anything.

Take a look at the case holders used for a Wilson trimmer. They hold a case on the body outside diameter.

Buy the Wilson holder you need or make one yourself.

Tap the case into the case holder.

Use a 1" 5C collet with a stop on the inside threads. You might figure out a way to use a chuck but collets are far better for this work.

Hold the the case holder and case with the head against the collet inside stop to control the length.

Trim the case with your carriage locked to the right length. If you have to cut off an over length case during case forming you can grind your tool to do that too.

Then deburr inside and out

Remove the case holder from the collet and tap the case out. Make sure you do not leave any shavings inside the cases.

[Tazza]

I like the idea, but it does take time.

I was considering making something so i could make .38 super comp cases from standard .38 super cases. The super comp cases have no rim, unlike the .38 super cases that do have a very small rim. A simple punch setup can remove the rim, the issue is with the small rim gone, the groove for the extractor is smaller than it should be. For playing that is fine, but you want 100% reliability for competitions.

Without a current solution, i just suck it up and buy super comp cases when i get low. I always come home with fewer than i went there with :(

[Kilroy08]

Hardinge DSM 59. Machinable collet that has been bored to grip on the rim. Set up a cutter, OD deburr, and ID chamfer tool in the lever action indexing turret. If you were slick... Collet grips on rim and is also cut with a chamber reamer and a stop set in the collet. Grip on rim, then flip around and grip case while the primer pocket is reamed.

It would be the Cadillac of case trimmers, also way too expensive for the average yeoman.

[rondog]

FWIW, I love my Giraud Trimmer, it's perfect for trimming bottleneck rifle brass to length, deburring, beveling and chamfering all at once. Even does .30 Carbine with a little more effort.

But I'd kill to have a small lathe in good shape! I was a machinist for many years and got real used to having access to lathes and mills. When you don't have that access any more you really realize how valuable they are. I think of things weekly that I could use a lathe for.

[bangerjim]

IMNSHO....

I use machinable hard brass 5C collets all the time. Not that expensive, but I feel an overkill for the simple process of trimming a case. There are way too many good and viable case trimmers out there to mess with a clumsy and time-consuming lathe set-up. (And I have many decades of expereince with lathe and mill set-ups, usages, and machining techniques).

And why worry about the primer pocket at all? Reaming it will only lead to potential ill-fitting primers in a short time. I have a set of hand pocket cleaner/reamers and rarely ever use them. I don't concern myself with a little black in the primer pocket. Heck, I only clean my brass ever 4 or 5 reloads anyway. I have never found clean & shiny brass brings any additional accuracy to actual shooting.

Just my observations.

[bangerjim]

FWIW, I love my Giraud Trimmer, it's perfect for trimming bottleneck rifle brass to length, deburring, beveling and chamfering all at once. Even does .30 Carbine with a little more effort.

But I'd kill to have a small lathe in good shape! I was a machinist for many years and got real used to having access to lathes and mills. When you don't have that access any more you really realize how valuable they are. I think of things weekly that I could use a lathe for.

You should be able to find a good lathe on Craig's list in a big area like Denver. I would be lost without my 5 metal lathes, 3 wood lathes, and 2 milling machines! If I did not have any, I would go without food to afford one.

[EDG]

A lot of the purpose built trimmers will not cut off a case that was formed from a case .250 longer - that is unless you like generating a rat's nest of shavings for each case. A part off blade hand ground with an angle will easily cut off those long necks and trim in the same motion.
I read a lot of comments about the time burned so that must come from commercial loaders. If you comment you should provide some context because most of us are shooters not ammo manufacturers. The time it takes to load 500 rounds spread over a month is not very consequential.

Another thing that helps is to measure the length of your chamber and record that number.
Then DON'T TRIM until the case get close to the chamber length. Some military rifle chambers are 1mm that is .03937 longer than the trim to lengths in the manuals. You are kidding yourself if you think trimming a case .040 shorter than the chamber means much.
If your case necks get uneven trim the longer uneven cases.

[EDG]

Can you trim every case on the planet with your lee tool? Of course not.
But you can trim most with a 13" lathe. One of the little Hardinge 2nd op machines is very fast and you can do almost anything with them a lot faster than an engine lathe.


You can even make low pressure cases, lube sizer dies, nose punches, - check it out.

https://www.youtube.com/watch?v=RFlCp5x0nEo


With my press-held Lee trimmer, I can trim AND chamfer (inside and out) a case in 5-8 seconds.....lots faster than any lathe set-up.

At 20 seconds to ONLY trim, that is almost 3 hours to trim 500 cases! And you still have to chamfer them.

My philosophy has always been: use the correct tool and for the purpose it was designed for.
Guess that is why I have ever tool made by man.....and many of my own design.

But do whatever floats your boat.

banger

[smokeywolf]

I use a Wilson trimmer that I motorized.

For brass that requires not just trimming, but shortening, like making 45-60 from 45-70 cases I use the lathe.

[bangerjim]

Can you trim every case on the planet with your lee tool? Of course not.
But you can trim most with a 13" lathe. One of the little Hardinge 2nd op machines is very fast and you can do almost anything with them a lot faster than an engine lathe.


You can even make low pressure cases, lube sizer dies, nose punches, - check it out.


Well, I personally do NOT reload every case on the planet. Only normal standard calibers. Not that other stuff some mention on here.

If one loads those cals, then have at it with a lathe device. I will stick with my fast & efficient Lee product. And spend my lathe & mill time making scientific and antique instrument and clock reproductions & repairs.

banger

[Whiterabbit]

I've noticed a few references to people using laths for case trimming.
I'd like to know, what kind of chucking and tooling are you using or have found best ?

Any info and ideas appreciated, TIA.

Cheers, YV

Howdy YV,

I do 400 cases in 15 minutes on a lathe (personal best). That's trim, deburr, and chamfer.

Here's the caveat: I'm not making big cuts. No .1" reductions. Just normal trimming-once-fired-brass kind of trimming. Not "forming". That said, 400 in 15 min is not hard with my setup.

Here's how I do it:

#1: use LEE case trimmer plus piloted bits.
#2: set your cut length by trimming the pin if needed. For max speed you need to use a primer as the datum. I will be intentionally vague there. But you can use the standard twist chuck for the cases and probably get 150-250 cases done in 20 minutes or so.
#3: you put the CUTTER in your 3 jaw scroll chuck.
#4: you set up 3 bins in front of the lathe. One for untrimmed, one for trimmed, and one for cases you tried to trim but no trimming happened (aka no need to chamfer and deburr this bin)

The caseholder you will have to screw into a ball (like a muzzleloader shortstarter) or similar. If you don't need the lee chuck for datum, then you can just hold onto the case itself, like using a WFT chucked into the lathe.

you apply the case to the cutter by hand. While the right hand pushes the case into the cutter, the left hand grabs another untrimmed case. When right hand falls to drop the case into the trimmed bin, left hand meets the right for the case changeover.

Max time is spent applying brass to the cutter. It's very, very fast when setup right.

When finished, take the cutter out and put the debur in the lathe chuck and repeat the process, holding the brass by hand. 2x for debur and chamfer. Fast.

[douglasskid]

That made me head to the lathe to try.
THANKS

[EDG]

I will reload about anything including turning rims, cutting extractor grooves and making the reloading tools.
Because of the versatility of a lathe you can do things such as making cartridge cases from bar stock, reloading dies or reboring bullet molds.
The variety of that other stuff is handloading.



Well, I personally do NOT reload every case on the planet. Only normal standard calibers. Not that other stuff some mention on here.

If one loads those cals, then have at it with a lathe device. I will stick with my fast & efficient Lee product. And spend my lathe & mill time making scientific and antique instrument and clock reproductions & repairs.

banger

[Rick O'Shay]

152693This is what I did with my RCBS Trim Pro. Made life a little easier.

[Whiterabbit]

That made me head to the lathe to try.
THANKS

My best advice for perils and pitfalls:

Test cases for uniformity of length. Not all datum points are acceptable. For example, my first test was to punch the primers out of the brass, run the guide pin WAY long, (loctite in place), and put the shoulder of the pin on the inside of the case, letting the primer pin just spin freely out the back. Buzzed a few cases in there b hand and measured them. Not even close to accurate. you can get within a couple thou easy using different datum points. Or of course using the lee case chuck so the pin has a positive stop at the base of the cartridge.

[leadman]

I bought the new Lee trimmer and the power adapter. I use a Black & Decker rechargeable screwdriver. I do get some chips caught behine the blades on occasion and it changes the angles of the trimmer. I still like the older Lee trimmer with the case holder in an 18v cordless drill so it stays upright by itself. I clamp a small vise-grip on the cutter to make it easy to hold. I can either chamfer the case in the drill or use my RCBS Trim-mate.
I saw a gun smith use round white plastic, think it was Delrin, that he bored thru for the case and cut off at a certain length. He split one side of the plastic so when it was clamped in the 3 jaw chuck it held the case firmly. He use this setup only for some wildcat cartridges he would chamber customers guns for.

[rondog]

You should be able to find a good lathe on Craig's list in a big area like Denver. I would be lost without my 5 metal lathes, 3 wood lathes, and 2 milling machines! If I did not have any, I would go without food to afford one.
No $$$$ to buy one, no place to put one. Too poor, garage too small and packed. Recently got a better job, maybe we can move someday. Wife is all for it already.

5 metal lathes, 3 wood lathes, and 2 milling machines? You suck! Suppose there's 5 or 6 welders there too.....

[rbuck351]

Whiterabbit
That is similar to what i have been doing except I was using the Lee case holder and stock length pin gage. Your method is now my new way. I don't think there is any way that could be faster unless you built a machine you could dump the brass in and push a start button. Pick up a piece of brass, shove it on the cutter/length gage and drop. With a bit of practice I think you could get it down to 2 to 3 seconds per case. Even at 5 seconds per case it's 720 per hour without you turning anything. Thanks for that tip. Get enough people working on something and someone will come up a really good solution. This could be done on a drill press as well, just verticel instead of horizontal.

[Whiterabbit]

Well that is a change. I was crucified on a more snobby bulletin board for suggesting this method. Thank you for the affirmation.

[rbuck351]

Some folks are afraid to admit that someone else may actually have a better idea.

[Huvius]

There was some talk of doing 577-450 on a lathe and it would be just the same method as how I trim my 577-500 on the lathe.
No way would I try to clamp the brass in the collet!
Simply make a mandrel which fits well into the neck which is held in the chuck. As long as the internal depth is consistent with your brass, and you have a live center to hold in the primer pocket, it is a snap!

I just posted this on Nitro Express so some of you may have seen this already.

I set up my mandrel (.5" scrap stainless steel) and the cutter with a factory formed Bertram 577/500 No.2 case and then slipped a case formed from the basic 577/500 brass and found that there was quite a difference.
Anyway, once I adjusted the cutter to work with the new cases, I found that these are in fact very consistent internally and began the trim. I measured each piece and there may be .001" off here or there but not enough to worry me.
Also, I have a live center for my tail stock which allows me to hold center while firmly pressing the case onto the mandrel. That kept the case from spinning on the mandrel and after a few cases, I got a feel for how much pressure I was applying with the tail stock and tried to stay consistent with that.


Here are some pictures:


This method works great right from full forming and FLS in the reloading die.
The SS mandrel.
I cut a little relief into it with the same cutter I am using for the brass. The cutter is a little angled for two reasons. First, as the cutter advances through the neck wall, the remnant is pushed down the mandrel away from the case mouth. This makes it easy to see when the parting is complete.
The second reason is because I once dropped my deburring tool and one of the legs broke off at the tip... so now it will not chamfer a case as big as .500! I figure angling the cutter will give me a bit of a chamfer on the case while cutting it. Also, I hold a bit of steel wool at the cut before removing the case from the mandrel to really smooth it out.


http://i251.photobucket.com/albums/gg312/Huvius/500%20pic1.jpg (http://s251.photobucket.com/user/Huvius/media/500%20pic1.jpg.html)


sliding onto the mandrel toward the relief groove.
That's a little ring of brass in the groove from the previous case.
http://i251.photobucket.com/albums/gg312/Huvius/500%20pic2.jpg (http://s251.photobucket.com/user/Huvius/media/500%20pic2.jpg.html)


Fully seated.
http://i251.photobucket.com/albums/gg312/Huvius/500%20pic3.jpg (http://s251.photobucket.com/user/Huvius/media/500%20pic3.jpg.html)




This is the live center on the tailstock holding the case in place.
http://i251.photobucket.com/albums/gg312/Huvius/500%20pic5.jpg (http://s251.photobucket.com/user/Huvius/media/500%20pic5.jpg.html)




Cutting.
http://i251.photobucket.com/albums/gg312/Huvius/500%20pic6.jpg (http://s251.photobucket.com/user/Huvius/media/500%20pic6.jpg.html)




And the finished length.
http://i251.photobucket.com/albums/gg312/Huvius/500%20pic8.jpg (http://s251.photobucket.com/user/Huvius/media/500%20pic8.jpg.html)

http://i251.photobucket.com/albums/gg312/Huvius/500%20pic10.jpg (http://s251.photobucket.com/user/Huvius/media/500%20pic10.jpg.html)

Another benefit to doing cases on the lathe is that the rims can be trimmed back if needed while it is on the lathe although a multi-tool holder would be best for that.

[jmorris]

I have done it on a CNC mill before.


https://www.youtube.com/watch?v=LaBON6F1LlQ

A Dillon trimmer is a LOT faster (over 1000/hr) is pretty easy and costs a lot less.

[EDG]

This can be fast right up to the instant you stuff your hand into the spinning 3 jaw chuck.
You would be safer using a collet chuck or an electric drill.
I just think pushing with any force toward the chuck is eventually going to get you hurt. That is based on about 10,000 to 12,000 hrs running an engine lathe and a wide variety of turret lathes.


Howdy YV,

I do 400 cases in 15 minutes on a lathe (personal best). That's trim, deburr, and chamfer.

Here's the caveat: I'm not making big cuts. No .1" reductions. Just normal trimming-once-fired-brass kind of trimming. Not "forming". That said, 400 in 15 min is not hard with my setup.

Here's how I do it:

#1: use LEE case trimmer plus piloted bits.
#2: set your cut length by trimming the pin if needed. For max speed you need to use a primer as the datum. I will be intentionally vague there. But you can use the standard twist chuck for the cases and probably get 150-250 cases done in 20 minutes or so.
#3: you put the CUTTER in your 3 jaw scroll chuck.
#4: you set up 3 bins in front of the lathe. One for untrimmed, one for trimmed, and one for cases you tried to trim but no trimming happened (aka no need to chamfer and deburr this bin)

The caseholder you will have to screw into a ball (like a muzzleloader shortstarter) or similar. If you don't need the lee chuck for datum, then you can just hold onto the case itself, like using a WFT chucked into the lathe.

you apply the case to the cutter by hand. While the right hand pushes the case into the cutter, the left hand grabs another untrimmed case. When right hand falls to drop the case into the trimmed bin, left hand meets the right for the case changeover.

Max time is spent applying brass to the cutter. It's very, very fast when setup right.

When finished, take the cutter out and put the debur in the lathe chuck and repeat the process, holding the brass by hand. 2x for debur and chamfer. Fast.

[Whiterabbit]

This can be fast right up to the instant you stuff your hand into the spinning 3 jaw chuck.
You would be safer using a collet chuck or an electric drill.
I just think pushing with any force toward the chuck is eventually going to get you hurt. That is based on about 10,000 to 12,000 hrs running an engine lathe and a wide variety of turret lathes.

You are absolutely right EDG. Every activity, whether it is case trimming, reloading, firing a gun, riding a bicycle, has some associated risk. To engage in any of these behaviors and much more without understanding the risk involved can increase the chances of injury up to and including death. If the risk cannot be mitigated sufficient for the comfort of the person engaged in that task, it's better that they don't engage in the task. Knitting is always available as a low injury risk activity.

[EDG]

You don't really have to avoid the task just use a better or safer process. The problem with a lathe is if you have never had or seen a significant wreck on one you may not anticipate the danger. Many workers do not anticipate the increased chance of injury that goes with repetitive operations that may last for hours. You can easily do 50 or 100 or maybe 200 cases without a problem but somewhere between 200 and 10,000 cases you may goof.
I am sure there are people with repetitive motion injuries from knitting.



You are absolutely right EDG. Every activity, whether it is case trimming, reloading, firing a gun, riding a bicycle, has some associated risk. To engage in any of these behaviors and much more without understanding the risk involved can increase the chances of injury up to and including death. If the risk cannot be mitigated sufficient for the comfort of the person engaged in that task, it's better that they don't engage in the task. Knitting is always available as a low injury risk activity.

[Safeshot]

I still like to use the Lee Case Trimmer in a Drill Press. Set the drill press spindle stop so that the spindle stops just as the pin touches the table. This prevents extra pressure being applied to the pin and prevents excessive wear or damage to the pin. (The trimmer stud and pin control the trim length and it is very accurate.) Just hold the case in position (a nitrile rubber glove on the hand holding the case in position makes it a lot easier) or use pliers with leather padded jaws to hold the case in position, if desired. This approach is so fast that most people that have never tried it will not believe how fast it really is. Just my opinion.

[Huvius]

I guess the point is, that if you are needing to trim a lot of brass, there are much better methods than using a lathe.
However, if you are working big cases and are needing to trim less than 100pcs or so, the lathe can be a very good way to do that.
I am trimming these particular cases because I started with 577 basic brass which means that I HAD to trim them. I doubt that I will need to trim them again ever again being big bore black powder rounds. That is my hope anyway.

[GONRA]

GONRA uses my boyhood 12" (between centers) Craftsman lathe (screw cutting, only $50 in 1950's)
with a modern imported (pricy) 1/2-20 threaded 3 jaw universal lathe chuck and
home made tailstock support / usual el cheapo Harbor Freight carbide insert cutter, for .50 BMG brass trimming.
(Case head backs, stops inside this small chuck for length reference.)
Verked great for me - 1200 rd. Scrap Dealer case prep a couple years ago.
(For a great hobby project, use yer BIG LATHE to make proper feed screws / 1 mil dials for this little lathe. Its worth it!)

[fjruple]

Due to bad old hands I have a cheap Harbor Freight lathe which I use to trim cases for 35 Winchester Self Loading Cartridge, make .455 Webley MKII from .45 Schofield, .45 Cowboy from .45 Colt and current rimming 5.56mm to 5.45mmx39 Russian. I use a RCBS Trim Pro Cutter and a Universal Holding fixture. I have made mandrils, made firing pins and turned pistol barrels on the lathe. attached is a picture of my lathe setup for trimming 5.56mm brass to 5.45mmx39.

--fjruple

165529

[shortfal]

For shortening .308 cases to convert to 8 Kurz I turned a piece of round stock with a pocket about .063 deep to accept the case head and a shaft just under boolit dia. that goes thru the case with a tit to go in the flash hole. it extends about an inch out the mouth to a diameter that is large enough OD to have a center drill cut a recess in it to accept a live center.
The shaft traps the case between it and the pocket in the piece of round stock in the chuck. I part off with a sharp piece of cutter bit about .050 wide. With care I can change cases without stopping the lathe.

Pete in St. Louis

[Nueces]

Nicely done, shortfal.

[shortfal]

Nicely done, shortfal.
Thanks, Works really fast and dead on every time for whatever length you want. It's the deburring, necking, inside reaming, final trim and another deburring that eats up the time.
Pete

[marlinman93]

I've tried trimming long cases in my lathe, but it is time consuming. I use a round rod inside the case neck, and clamp the cases by the neck. Then I turn thee case off, and catch it in a pan sitting on the ways. I have a stop built, so it's easy to get the same cut each time, and I still final trim in my case trimmer.
But I stopped using the lathe when I saw someone using a miniature chop saw to rough cut cases. I got one on sale at Harbor Freight that has a 2" dia. blade, and it's so much faster! I simply set the stop for the cut I want, and chop the cases off. Then on the trimmer to make the final cut. I can cut them off faster than I could load them in my lathe.

[EDG]

The fastest and easiest way to hold cases in your lathe is to buy or make the case holder like this one by Wilson shown being used in a Wilson trimmer.
You tap the case into it and the case locks on the taper just like a Morse taper.

Then hold the case holder in a 5C 1" collet. You could also hold it in a 3 jaw chuck but you will eventually get chuck marks if you over tighten the chuck.


167834

[Lead pot]

You guys are making a lot of work trimming cases.
I used to use a chainsaw chain sharpener first, then I saw one of these little 2" cutoff saws on sale for around $30. at Harbor Freight and I got it because it is a high RPM saw that turns at over 10,000 RPM what is needed for a smooth burr free cut.
I made a block with a groove to lay the case in and it makes a positive stop for a very precise length cut from the front of the rim. This eliminated the error from the different rim thicknesses. There aren't to many case trimmers that will trim from the front of the rim where you need a consistent head space. This is a plus to hold the depth the case is in the chamber. I don't need to follow up using my Wilson case trimmer, the cut is the same cut for cut. This particular case is 2.413" long ahead of the rim that fits my chamber. So far I have cut more then 1000 cases using the same blade and it's still sharp.
I just trimmed over 200 cases in less then 1/2 hour and they are all the exact length from the few I measured to make sure my wood block has not moved.
Now all I have to do is chamfer the case mouths and they are ready to load for the Quigley and a few other gong shoots I will make in a few weeks.

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[WFO2]

I use a Littlecrow checked in a drill .https://littlecrowgunworks.com/product/worlds-finest-trimmer-wft/?v=7516fd43adaa

[superc]

LoL, I recently trimmed a batch (maybe 80?) 44 Special and 44 Magnum brass down to 44 Bulldog dimensions. For shortening I found the lathe cutoff bar to be horrible. Can we say burr city?
After wasting my time on 10 rounds, I next drilled a hole of 44 OD dimension into a 1" carbon 4140 steel block, hardened it to about 50 and mounted the cases in that in my mill vise. Then I simply dropped a 3/4" endmill on each one at about 200 RPM. Very nice 12" chips and no heavy burring when done. Also with practice changing out the cases in the vise went pretty quickly. The only downside I experienced was sometimes the case would spin in the jig so that the headstamps were no longer readable. No big thing because they weren't Special or Magnum anymore anyway.