Making Hornady cases?

[theMadAlaskan]

I have been making cases on my lathe for my Hornady OAL gauge using a size L drill and 5/16-36 tap. The thing is I'm not a machinist – more of a mechanic who happens to own a fancy power tool – so I've had about as many failures as successes.

What I've been doing is using the three jaw chuck to hold a fired case. Sometimes it slips during the tapping operation marring the case. This happens even though I'm careful to frequently back off and clear the chips. Sometimes it even happens when I'm backing off.

Other times the case is simply too distorted from the jaws to fit smoothly in the chamber. I could run it through a FL die but then I would need to expand the neck enough for the bullet to slip fit. Maybe that's the answer but I don't have a way to do it. (Dies with interchangeable neck bushings?)

I have also tried using a piece of rubber to hold the case but that didn't help much and seemed like it would produce too much runout anyway.

Any tips/tricks/hints? Thanks!

TMA

 

[TroyMN]

I use a piece of Oak with a hole drilled so the case will almost fit in to the base. I then take and cut the oak with the grain through the hole, but not all the way to the end of the board. Its kinda like a very small barrel vise. Clamp in vise on drill press, 2 steps drilling. I start the tap in the drill chuck NO POWER just turn it in, finish with the wrench.
Hope this might help. I did a .223 case also and that does not leave much room to be off center.
Troy

 

[spclark]

I use a Wilson trimmer case holder when I'm doing stuff like this on cases. Since I use a Wilson trimmer I already have a case holder for the cartridges I shoot.

Also helps make cases easier to hold on to when doing stuff like flash hole de-burring. Older hands appreciate the larger diameter workpiece.

 

[jscandale]

TMA,

I make them very frequently for the wildcats that I sell. I just chuck a case in a 3 jaw and spin it about 300 rpm. First drill with a letter K drill and then install the the tap in the drill chuck, at the same rpm and let the tap feed its own way in the case while slightly applying pressure on the back of the tail stock so that it will slide easily when the tap is drawn into the case. I usually stop the feed with the foot brake and then run the lathe in reverse while slightly pulling on the tail stock to help it along. That's it.

JS

 

[shortgrass]

TMA,

I make them very frequently for the wildcats that I sell. I just chuck a case in a 3 jaw and spin it about 300 rpm. First drill with a letter K drill and then install the the tap in the drill chuck, at the same rpm and let the tap feed its own way in the case while slightly applying pressure on the back of the tail stock so that it will slide easily when the tap is drawn into the case. I usually stop the feed with the foot brake and then run the lathe in reverse while slightly pulling on the tail stock to help it along. That's it.

JS

+1 A good dose of Tap Magic helps. I use a letter "J" drill and get full threads.

 

[Mega]

I have made a couple of dozen without a single hitch.

I use a friends small lathe with three jaw chuck and make sure the case head is flush to the outside of the jaws. I use a 9/32" HSS Drill and manually feed to ensure I get a continuous cut. I then install the 5/16-36 tap in the headstock and manually spin the chuck allowing the tap to self feed, the headstock is not locked in position. I lube the tap with mutton fat and reverse manually quite often to clear the tap.

 

[Grimstod]

I Feel primitive now. I have been doing this with rubber typed plyers and a drill press. lol

 

[theMadAlaskan]

Thanks to all. I knew there had to be an easy way to do it - since I usually find the hard way!

 

[Erik Cortina]

I don't use my big lathe for this. I find my mini-lathe works perfect for this. I chuck the case with the head flush with the jaws and do it just like jscandale. When I tap the hole, I loosen the tail stock and push it by hand so that when the tap engages, is sucks the tail stock in. I slow it down for tapping to about 100 RPM.

If you distort case, you can use a FL sizing die to correct it. After using a F/L die I use a collet bullet puller and slide a bullet in and out of the case a few times to loosen neck. I then chuck up a bullet in the mini-lathe or even a drill and apply IOSSO to the bullet and spin it inside case neck. I do this until I get the fit I'm looking for. All this takes less than 10 minutes.