Trimming the top of a mold?

[fatelk]

I have a Lee 230-TL-TC six-cavity mold I bought last year and I've never been real happy with it.

Part of the issue was the diameter of my barrel, but I got that resolved. I am lube-sizing the TL boolits and that works OK, except for the bevel-base thing.

Another issue is the weight of the boolits. I've now been using half and half WW and soft, and with that alloy the boolits come out at 240 grains. I'm just not real happy with using such heavy boolits and having to seat them as deep as the TC design dictates. I don't like beating up my old Ballestor Molina, and especially not grampa's old Govt. Model, with heavy loads.

So here's my thought: can I just find someone with a mill and flycut a little off the top? It seems that that would take care of both the weight and the bevel-base. I'd like to have the boolits around 220-230gr, and don't think it would take much.

Side question: Lee says they base their weights on al alloy with 10% tin. Are they smoking something they shouldn't? Does anyone actually use 10% tin these days? I wonder why they aren't a little more realistic?

[RayinNH]

fatelk, yes you could have someone flycut the molds. Just make sure the cut ends up on a drive band and not a lube groove or else you won't be any better off than you are with a bevel base, just lighter...Ray

[44mag1]

I want to do the same thing to my lee 175 10mm TL mold. I cant stand the bevel base. I dont want to spend too much having it done either.

[RobS]

I took the Lee TC 230 grain regular lube groove design 6 cavity mold and used a large file to work the mold enough to take the BB out. It takes time and patience and consistent pressure as you work the top of the block. I also rotated it 180 degrees every 20 to 25 strokes to keep a balance from both ends. I did this to a Lee 200 RF grain 6 cavity mold as well as it came to me with the sprue plate end pinched on the corner of the block so the sprue plate never would run straight.

I took enough out of the 230 grain bullet to take out the small bevel and it would then weigh in at 225 grains where as it use to be at 240 grains from WW. The Lee 200 grain RF didn't take as much to fix so a once 210 grain bullet ended up at 205 grains.

There is the reality that one can mess up a mold doing it this way as you are flying solo and if you are not one that is handy and have a feel for hand tools then this may not work out too well for you therefore having a shop do it for you will possibly work out better. Anyway, I am two for two with the 6 cavity molds and have worked a lee 2 cavity block to take out the heavy gulling from a previous owner. By the way with a 2 cavity mold a person can very well end up re-tapping a new sprue plate bolt hole as well as a tapping a side set screw as many times backing out the factory sprue plate screw ends up being, let's say, quite challenging.

[fatelk]

I took enough out of the 230 grain bullet to take out the small bevel and it would then weigh in at 225 grains where as it use to be at 240 grains from WW
Excellent info, sounds like exactly what I want to do.

I worked as a machinist for several years. The shop I worked in is a couple hours away, but if I get down that way I'm sure he would let me set it up in the old Bridgeport and run a flycutter over it; wouldn't take but a few minutes. I might take just a little off my .40 mold as well.

Come to think of it, a local guy my dad knows a couple miles down the road has a small machine shop. Maybe I should talk to him.

This place is the best!

[WHITETAIL]

Yes, take it to a local guy and see if he would do it.:smile:

[Cap'n Morgan]

An ordinary lathe will easily do the trick. You can even use a standard 3-jaw chuck to hold the mold, but don't run run the lathe at more than 300-400rpm as it will be off balance. Face off the mold with no more than .01 per cut.

[felix]

You mean we really do have a RPM threshold? Sounds familiar, does it not? ... felix

[cabezaverde]

Board Member Buckshot does a great job on this type of work. Might want to track him down.

[Cap'n Morgan]

You mean we really do have a RPM threshold? Sounds familiar, does it not? ... felix

Rpm threshold and cast boolits? I have absolutely no idea of what you are talking about...[smilie=1:

Actually, an unbalanced load in a lathe is a good example of what forces are involved in spinning objects. If run too fast the lathe can literally start to walk across the floor.

A toolmaker friend of mine worked in a shop where a guy was facing off a heavy, unbalanced part on a large CNC lathe. Now, one of the smart things with CNC lathes is they will keep a constant cutting speed when facing off, by increasing the RPMs as the tool tip approach the center until it reach the programmed max. Unfortunately this guy forgot to add such a programmed max, and when the tool neared the center the lathe took off like a bat out off hell, flinging the part off the faceplate. The several hundred lb part put a large dent into an I-beam in the ceiling above, and then crashed down onto the lathe ruining it beyond repair.

[felix]

No problem, Cap'n. When you have time check out the threads involving RPM featuring "Larry Gibson" as principal. I find it interesting that you mention the threshold, even though with a different application. ... felix

[Cap'n Morgan]

Felix,
I was just trying a little irony. In fact; I've been following the RPM and 6.5 x 55 Swede threads with great interest.

[Elk Country]

I did exactly what you are talking about to a 2-cavity Lee 230gr. TC mold. I fly cut the top of the mold .068". Now the bullets drop out at 202gr. and are flat base. They load and shoot just like I wanted and I plan on buying another mold to modify to increase my production. The nice thing about the LEE molds is that they are cheap and if you screw one up it doesn't cost $60-$80 to replace them!
If you can find someone with a mill, that is the way to go. I'm sure other methods work, but fly cutting the mold on the mill is the best.

Elk Country

[OLPDon]

I have 2 trains of thought here Once you Fly cut your mould that is it either it works or it don't. That being said, you could take some cast boolits face off the bevel load and shoot see how that works. Next thing would be to bore out one of the cavity's to remove bevel. Cast load and shoot. Seeing as how your intent is to remove bevel & change it could still be done later. Carpenters will tell you mesure twice cut once.

I know its more work and time, but best way to save the cost of a new mould if Fly cut or refacing mould don't produce
Don
The boring out of one bevel you can do yourself

[Shiloh]

Had two molds flycut to remoce the bevel base. I'm going to have it done with the same mold as you. That would be a LEE 6 Banger 230 TCTL boolit. Mine drops at 238 gr. with range scrap.

Shiloh

[Buckshot]

...............Yup, flycutting is the way to go!

http://www.fototime.com/9343DBFA31116FB/standard.jpg

..............Buckshot

[fatelk]

I haven't gotten time yet to check with the local guy yet, but I did happen to find my old flycutter in the garage, in case he doesn't have one. I made it as a project when I took some machine tool classes at a community college about 15 years ago. I've often wished I could afford a lathe and a mill. Someday..

Buckshot, thanks again for the custom sizer die. It works great, and I worked up a great load for my .45 with no leading.:) I'm hoping that it still shoots just as good when I get this mold trimmed.