modifying dies for tru-line junior.

[Steelpounder]

hello all, I have had a TL junior press for a number of years. When I got it, it was set up with 38/357 dies. I would like to set it up to reload 9mm. after roughly five hours of searching I have learned two things. 1) there dont seem to be any 9mm dies available for this press. And 2) there no longer seems to be anyone making a conversion die plate. Which brings me to my question.

Has anyone here ever turned down and rethreaded an existing set of dies to fit this press? it seems it would be easier than making a full set of dies.

My idea is to use this little guy for pistol rounds only. I have found dies on the Bay for the other calibers that I want to use this press for. so modifying an existing set of dies seem to be a viable alternative. this is just for nostalgia as I have other presses that I can use and I already have a second set of 9mm dies.

[Green Frog]

If you are or can find a sufficiently skilled machinist, the answer to your question is a qualified yes. The biggest hurdles will be dealing with the hardness of the “big” dies and for some lathes at least being able to cut 30 tpi threads. But there are 9mm die sets out there for the 310 tool at least, and I bought one of those sets to satisfy my “small die” needs. I will admit that although TL Jr die sets (with a FL sizing die) were catalogued, I’ve never seen a set for sale. I periodically FL size my 9mm cases on the big press and do the other tasks with the smaller dies.

Froggie

[Dan Cash]

I bet you can buy a Dillon Square Deal press set up for 9mm cheaper than you can get existing dies turned down and threaded.

[Green Frog]

Hey SP, a simpler strategy might be to find a scruffy set of 310 dies for the 222 REM (commonly available) and ream them for 9mm. You could even have a FL sizing die this way! You could buy a case expander for a 38 Spl and turn it down slightly if needed. The only thing you might have to make completely from scratch would be the bullet seating plug. If I were going to fire up the lathe for this project, I believe this would be my plan.

Froggie

[Steelpounder]

I bet you can buy a Dillon Square Deal press set up for 9mm cheaper than you can get existing dies turned down and threaded.

thank you for the very un-helpful reply. if that was what I wanted to do I would simply load the 9mm conversion in one of the Dillon progressive presses that I already have.

[Steelpounder]

If you are or can find a sufficiently skilled machinist, the answer to your question is a qualified yes. The biggest hurdles will be dealing with the hardness of the “big” dies and for some lathes at least being able to cut 30 tpi threads. But there are 9mm die sets out there for the 310 tool at least, and I bought one of those sets to satisfy my “small die” needs. I will admit that although TL Jr die sets (with a FL sizing die) were catalogued, I’ve never seen a set for sale. I periodically FL size my 9mm cases on the big press and do the other tasks with the smaller dies.

Froggie

thank you greenie, I am not sure if my big lathe will cut 30 tpi but I am pretty sure I can program the little cnc lathe to cut them. I dont know the hardness of the die body but i would think carbide tooling wont have a problem cutting the steel in body.

do you of any other problems I might run into? other than possibly screwing up a set of dies?

[n.h.schmidt]

Likely only the sizer die will be hard. It can be made soft to cut threads and then re hardened. I have done so before. Finding plain steel 9mm dies can be a problem though.

[ascast]

9mm sets are out there but they are not common and they go for insane money, like $150 per set, maybe not complete. I thought I had some pieces but can not locate. I like Mr Frogs idea, but I think I'd start with a 30-06 die as they are common. I might could send you one. Did you post on the 310 swapping board? Maybe you could become they guy who makes new tops for the juniors.

[Steelpounder]

9mm sets are out there but they are not common and they go for insane money, like $150 per set, maybe not complete. I thought I had some pieces but can not locate. I like Mr Frogs idea, but I think I'd start with a 30-06 die as they are common. I might could send you one. Did you post on the 310 swapping board? Maybe you could become they guy who makes new tops for the juniors.

thank you, Ascast, no, never posted on the 310 swapping board. I had thought of shortening a set of 38/357 dies but discovered that the are not the same diameter. my only problem with the idea of shortening a set of triple duce dies is having to buy a carbide reamer for the conversion as I dont think a HSS reamer will cut them. I currently have two sets of 9mm dies, the RCBS dies are not carbide and were obtained in a lot of stuff that I got at a yard sale for a really good price so even if I were to screw them up it wouldnt be a huge loss to me. I have a bunch of barrel cutoffs that I can do some experimenting with before tackling the RCBS dies. i may try to draw a new die plate and see if I can make one for the jr but I really suck at cad so that is a winter project

if anyone out there has a cad drawing they want to share I would give making a plate a try though

[GONRA]

30 TPI can be made with olde Craftsman 12 inch lathes, many others.
YOU have to verk out the Gear Train for 30 TPI for the lathe used.....
(Hope ya'll like math! Have Phun!)

Teen Ager GONRA cut lottsa 30 TPI's for reloading dies.....
(1950-60's - Never kept track of the gear train SORRY.....)

[gunther]

If you have a local friend who has a set of Lee 9mm carbide dies, it might be worth it to measure the sizing die to see if a turn down and rethreading would leave the carbide insert in place. The die body might be pretty soft. The carbide insert does the work.
The flaring die body may be aluminum. And the seating die might be pretty soft.
RCBS seems to harden nearly all their dies. I've cut a sizing die with a carbide rod saw, but it was a job.

[Steelpounder]

If you have a local friend who has a set of Lee 9mm carbide dies, it might be worth it to measure the sizing die to see if a turn down and rethreading would leave the carbide insert in place. The die body might be pretty soft. The carbide insert does the work.
The flaring die body may be aluminum. And the seating die might be pretty soft.
RCBS seems to harden nearly all their dies. I've cut a sizing die with a carbide rod saw, but it was a job.

thanks Gunther, I have a look at my dillon carbide dies and do some measuring. do you happen to know what material RCBS uses for their dies? I cant imagine 4140 being hard enough to give any trouble using carbide inserts.

[uscra112]

I've run across a Lee die that appeared to be nitrided, not through-hardened. Once I got under that hard skin with a carbide tool the core cut like butter.

I've recently reamed a 310 muzzle-resizer die out in the course of making a special. It was hard enough to seriously strain a HSS reamer, and the heat expansion caused the ID to wind up undersized. This might not have been a problem if my lathe had flood coolant, but it doesn't.

Just noodling around - a 3/8 drill bushing might size down 9mm brass enough, and that "special" I was making used a 1/2" OD drill bushing, which was why I was reaming it out. Think that through.

[Steelpounder]

I've run across a Lee die that appeared to be nitrided, not through-hardened. Once I got under that hard skin with a carbide tool the core cut like butter.

I've recently reamed a 310 muzzle-resizer die out in the course of making a special. It was hard enough to seriously strain a HSS reamer, and the heat expansion caused the ID to wind up undersized. This might not have been a problem if my lathe had flood coolant, but it doesn't.

Just noodling around - a 3/8 drill bushing might size down 9mm brass enough, and that "special" I was making used a 1/2" OD drill bushing, which was why I was reaming it out. Think that through.

just thinking about this it seems to me that a 3/8ths bushing would possibly reduce the case too much. unless wall thickness of the case was .011 or there abouts. however I fail to see the connection to my question!!

[Char-Gar]

If I wanted to pursue your course, I would open up the turret holes to the next larger common thread and turn the dies down to the same common thread size.

[uscra112]

Where an appropriate size is available, you can make a sizer by pressing a bushing into a bored-out 310 die body. It's regularly done to size .32 Colt. I used one to make a muzzle resizer for my reloadable .25 Stevens rimfire project, and yet another to make a .25-20 SS muzzle resizer in a 310 body. Here's an example of the .32 Colt version. In this case the bushing is a slip fit and uses spacer sleeves to keep it in place, because it's designed for tong tool handles. For a TL Junior it obviously would have to press into the die body.


Another potential source of bushings is the bushing-type RCBS neck sizer die system, although they tend to be out of stock.

If that fails, it wouldn't be to much trouble to turn the bushing out of 41L40 and harden it, (with a torch, if nothing else).

[Steelpounder]

Where an appropriate size is available, you can make a sizer by pressing a bushing into a bored-out 310 die body. It's regularly done to size .32 Colt. I used one to make a muzzle resizer for my reloadable .25 Stevens rimfire project, and yet another to make a .25-20 SS muzzle resizer in a 310 body. Here's an example of the .32 Colt version. In this case the bushing is a slip fit and uses spacer sleeves to keep it in place, because it's designed for tong tool handles. For a TL Junior it obviously would have to press into the die body.


Another potential source of bushings is the bushing-type RCBS neck sizer die system, although they tend to be out of stock.

If that fails, it wouldn't be to much trouble to turn the bushing out of 41L40 and harden it, (with a torch, if nothing else).

Ok gotcha sorry for being dense. I have plenty of experience with with hardening and tempering steels. if I had a set of reamers I would simply make new dies for the Junior. I do have two sets of 9mm dies and enough machine tolls to turn them down and rethread them, hence my question. the one set I have I got in a box of stuff I bought at a yard sale. since I paid 20 bucks for the box of stuff and have taken more than 100 dollars worth of tools etc out of it It wont really cost me anything to try. but I thought I would ask if anyone else here had done something similar.

[Steelpounder]

If I wanted to pursue your course, I would open up the turret holes to the next larger common thread and turn the dies down to the same common thread size.

What would that gain me? I would be able use the dies I turned down but would no longer be able to use the 38/357 dies nor the 45 acp dies that I have for it.

[ascast]

thinking again, somebody did a project similar recently. They pointed out that brass sizing dies will do a life time of work if made from soft steel. If your brass is fairly clean, meaning no sand,grit etc. You might try that route is you can turn 30 TPI.

[uscra112]

I think we've about worn out the topic. As I posted, the only make of dies I know of that could be turned down and threaded for the Junior without annealing is the Lee. I've got a kiln for heat treating myself, but have done all my "special die" projects without firing it up. Always seemed easier to use OTS components.

Phil