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Buckshot
12-21-2007, 04:18 AM
..............I couldn't stand it so decided to be selfish and self centered. To the exclusion of all else, I decided to make a set.

This core mould is the first mould I've ever made. It turned out well and I learned some valuable lessons for the next one. I'd bought a 6' stick of common 6061 alloy aluminum that was 3/4" thick by 1.5" high. I also got a piece 1/4" thick by 1.5" wide (and 6' long). I'd made a few sprueplates out of it and it's worked very well for that.

To make the blocks I setup and bolted a webbed angle on a faceplate, and laid one piece on it. In previous checking, this extruded aluminum bar is amazingly accurate over it's length, varying no more then a couple tenths anywhere. So I didn't worry about it but found center and clamped 2 of'em together .

Valuable Lesson #1. Draw a plan with at least some rudimentary measurements so your envisioned 4 cavity blocks don't turn into 2-1/2 cavity blocks. Sheesh. Been here and done this before, but it's beginning to sink in ............ finally.

First up was to drill and ream for 3 alignment pins. That was pretty much done except for the 2nd. I forgot the reamer and wondered why THIS particular pin was so dad blamed hard to drive into it's hole. Once I realized what the issue was, I looked around to see if anyone had been watching. Luckily I was alone. I got them done, finally.

So then I got the blocks back on the faceplate and cinched down, and had actually marked the centers for each of the 3 cavities. It was SUPPOSED to have been a 4 cavity set but I'd used 1/4" holes for the alignment pin bodies and the opposing steel sleeves. Seems it's a pretty good idea to have material all around the holes, not to mention the pins. This meant I had to move them in. In was in the direction of the cavities. It wouldn't do to have the alignment pin holes intersect the cavities.

So I deleted a cavity and used the resulting extra room to make sure there was block material around the pins and their holes. As mentioned, so it's a 3 cavity now. I drilled and reamed each cavity. Then bored to size, and didn't bother to polish as they came out so nice. This proved out in actual use too! All you have to do it swing the sprueplate and turn the blocks upside down and the cores will slide right on out.

http://www.fototime.com/096CE7F75FAF235/standard.jpghttp://www.fototime.com/1E69FACFF7FA727/standard.jpg

So here tis. It's used with Lee 6 cavity handles.

http://www.fototime.com/025DBFFE3B48D69/standard.jpghttp://www.fototime.com/82E06994EA0F27E/standard.jpg

Yes, the right cavity adjusting stem is smaller (10-32) then the other 2 which are 1/4-28. The reason?:

Valuable Lesson #2. Have the base plate attached and use the correct tap drill size to drill through the blocks and base plate. You'll be assured the hole is truly centered to the cavity. What I had sone actually worked for 2 of the cavities. What I did was to turn a short centerpunch a thousandth undersized and inserted it into each cavity in turn, then giving it a good whack to produce a mark. I guess for that one, the ole MkI Mod I eyeball detector just wasn't up to the task of centering the bit in the punch mark in the drill press..

To rectify the situation I countersunk each side of the bad hole in the baseplate, screw in a piece of aluminum and then rivited it in place and re-drilled the hole. I had to go to the smaller size as the minimal offset in re-drilling probably would have just knocked out the upset piece of aluminum.

http://www.fototime.com/8ED8737B8004644/standard.jpghttp://www.fototime.com/B30E60AD133ACBC/standard.jpg

Left Photo shows the baseplate with the cavity adjuster screws. Top & bottom on the right are the flathead sockethead screws holding it on. On either side in the middle are the mould handle screws. Their heads are recessed down below the plate.

Right PhotoThe cylinders on the right are for setting the adjusment stems in each cavity. Each one to the right are 1/8" shorter, which was arbitrary. You place a cylinder into a cavity and close the sprueplate. Then screw the adjuster up to touch. Remove the cylinder and place it into the next cavity and repeat, and ditto a 3rd time.

There is no rhyme or reason for the lengths. The longest one was merely the longest length that could be cast and the 1/8" step down was just a number I pulled out of my............... ear. Since my Hi-Wall has a 18" twist the 2 longer ones will probably be useless as they produce a 320 and 338 gr core. Of course you will lose a bit in the core bleed die, but not really enough to satisfy the twist limitations. Maybe.

http://www.fototime.com/C0C4E6516E99C1A/standard.jpg

Just for fun, sitting here on the baseplate is an aluminum setting cylinder and on the right is the cast lead core. Believe it or not, that's a BORED finish in the cavities!

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

Buckshot
12-21-2007, 04:19 AM
Core Bleed Die................Actually the 2 swage dies were made before the core mould. The reason was that I don't have a milling machine at the moment and doing so requires I setup the lathe for it. It's just a PITA as after tearing down and re-setting up to mill, after you're done you then have to tear IT down and setup the regular cross slide and compound AGAIN.

http://www.fototime.com/AAF78FD5871D099/standard.jpg

So this is the Core Bleed Die setup. What is done here is that the cast cores are all swaged to (hopefully, ideally, usually) very close to the same weight. This is accomplished by actually bleeding off (squirting out :-)) a bit of lead from each core. If you look at the middle left of the die body you'll see a bright dot. This is the bleed hole. To the right of the die body is the base punch. In the Walnut Hill swage press the punch is stationary and the die moves up over it to compress the lead core. And to the far right is a pile of extruded lead. These are some old ones that were lying there so I used them as they're much easier to see then correct ones. On the extreme left is the core ejector. It blocks the bottom of the die cavity. Then the die is lowered off the base punch, the larger body of the ejector comes up against a stop. The die continues down and the rod of the ejector pushes the core out of the die.

Why these aren't correct is that they are way too much lead. Ideally you will have the core weights close to what you want. You DO want to extrude 'some' lead to be sure the core is compressed, but there is no reason to squirt a lead rope out! All you need to see is maybe 1/8" or a bit more movement in the bleed hole ie: rat turds and NOT pasta!. When compressing cores you want to REST the press for a few moments under compression. With the ram all the way up lead will come out rapidly at first, then slow and stop. When I've pushed the handle all the way down I do a normal ten count before ejecting the core. Like anything else, consistancy is the name of the game. Your cores should weigh within 2/10ths of less.

You do need a bit of lube. Lanolin works great. The old type case lube works well also. All you want is to touch the pad of your thumb and index finger to the pad and then kind of roll the cast core between them as you pick it up and put it into the die. If you use too much, since it isn't compressable it will form little dimples. or migrate to any wrinkles or depressions. Ideally, like a good boolit, once the core mould is up to temp you'll be producing good smooth solid cores.

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

Buckshot
12-21-2007, 04:19 AM
.................Final form die

http://www.fototime.com/311412CE238A334/standard.jpghttp://www.fototime.com/185F229A1B908B9/standard.jpg

This is the form die. Externally the same as the core bleed die, but no bleed hole. The base punch up on top. It also has an ejector assembly like the core bleed die only its much smaller in OD. I cropped it out of the pic. Dunno why but it happened. To the right in the photo is a formed core and a swaged slug. The formed core is NOT for the slug shown. The swaged boolit weighs 296.4grs and that core is about 320 grs which will probably be too heavy for the 18" twist in the Uberti Hi-Wall.

If the die looks like it might have flecks of lead on it and in the knurling, it does. Why does it? Well it's because it fell into the lead pot. We don't need to go there, as to how THAT happened but in case you were wondering, that's what it is. The photo of the base punch by it's oneself is just because I'm inordinately proud of it :-). It's the one I mentioned in the " Dumb deed and a valuable lesson :-)" thread, where I had to make a bracket to turn the Dremel into a toolpost grinder.

http://www.fototime.com/52F297DD71E4D34/standard.jpghttp://www.fototime.com/E65515E6568F4E4/standard.jpghttp://www.fototime.com/323655DA723CC97/standard.jpg

On the left is just another pic of a core, and a swaged slug. Again the core doesn't go with that slug. All the correct cores got swaged so I used what I had. In the middleis just a pic of a base showing how nice and sharp the edges are.[On the right is a closer view of the nose. All of the 296gr slugs were swaged as HP's. However I hadn't ground a HP pin yet so just used the flat nose ejector pin. The reason for the slightly raggedy perimeter is the nose part of the die (internally) closes down to a basicly infinitesimal tiny angle there at the hole where the ejector pin comes through. Unless quite a lot of pressue is applied, the lead doesn't completely fill this tiny angle all the way around. In order to form a nice HP, I need to grind an ejector pin with a radiused bit right there so it slightly reduces in diameter and the lead can fill in.

Normally, if used as it should be the way the ejector is currently set up the swaged slug would be a solid. Sometime back I had parted off varying thicknesses of 3/4" OD stock just to do this seat of the pants HPing. That is, one (or more) of these shim type discs go under the ejector pin body in the ram. This makes the pin ride higher in the die so the lead is swaged around it, and voila'! A HP is formed.

http://www.fototime.com/6DD15BDBE5D31B1/standard.jpg

These are 3 weights, and 2 nose types, and 2 lead alloys of boolits I've swaged up, fiddle-d-dinking around. On the left is a 320gr HP. In the middle showing side, base and nose is a sample of 80 that finished up at 296grs. These 80 slugs all weight between 296.4 and 296.6 grs. Of these 68 weigh between 296.4 & 296.5 grs. On the right is a 338gr solid, which I'm afraid will probably be too much of a good thing. I only have about 20 of these but I'll probably patch them up just so I can tell myself, "I told you so".

The 2 slugs on the left in middle were cast and swaged of lead and tin of a 1-20 mix. The solid on the right was 2 lead, 1 WW and a bit of tin so it's not a LOT harder. I figure about 8 bhn. I think I should be able to swage a 1 lead- 1 WW alloy without straining anything.

One other thing I'm really happy about is how each one of these dies and the mould turned out. The core mould has to produce a core that will 'just' go into the core bleed die, and then this must also 'just' go into the form die and result in a patchable slug to do what I wanted. A couple times during polishing when I wasn't so sure! However, they do nicely slide from one to the other just like someone planned it that way, ha! What I wanted was a slug to finish up before patching to be just AT bore diameter. This way I can seat the patched slug out kind of like a bore rider, and have the patch bump up against the leade a bit. As it turned out the finished boolit is a trifle over .373" and I'd slugged the breech end of the barrel at .373", so we'll see. At the muzzle the bore is .371".

All I have to do now is find the tiome to patch them up.

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

Lloyd Smale
12-21-2007, 06:39 AM
how much would you charge to make me a core mold for my 41 mag swadging set?

garandsrus
12-21-2007, 10:20 AM
Buckshot,

Excellent write up! Thank you!!!

A few questions on the core die:
o How did you secure the steel inserts into the blocks? Did you knurl them and make them a press fit?
o Did you need to do anything to allow the mold to vent?
o Are the alignment pins just turned pieces of steel?

I would also like to make a .22 cal core bleed die. I have a couple questions on this one also:
o How do you lock the ejector in place (or whatever fills the hole in top) while bleeding the core?
o Does it matter where the bleed hole is located?
o How do you adjust the weight of the core? Do you adjust the height of the die or where the ejector rod "locks"?
o What step did you need the mill for?

If you have any additional tricks/thoughts, I would appreciate hearing them...

Thanks again for the write up!

John

Buckshot
12-22-2007, 01:53 AM
Buckshot,

Excellent write up! Thank you!!!

You're welcome.

A few questions on the core die:
o How did you secure the steel inserts into the blocks? Did you knurl them and make them a press fit?

Thought about it, but just used an interferance fit.

o Did you need to do anything to allow the mold to vent?

Nope.

o Are the alignment pins just turned pieces of steel?

Yup, nothing magic. !/4" steel turned down to the insert's ID minus a thousandth.

I would also like to make a .22 cal core bleed die. I have a couple questions on this one also:
o How do you lock the ejector in place (or whatever fills the hole in top) while bleeding the core?

I take it you mean if used in a reloading press with the base plunger in the ram? In that case, one way would be to bore the die body internally to a larger OD at the top. Then thread this to take an adjustablae stop. The threaded stop would be bored through. Then you'd have a pin turned to the ID of the core bleed bore. At a suitable distance allowing a reasonable amount of up and down adjustment there would have to be a collar on the pin. This would abut the face of the adjustable stop threaded into the top of the die.

o Does it matter where the bleed hole is located?

You wold have to decide the lightest slug you'd be liable to swage. Probably 32 grs or so. Put the hole in the middle of this distance. You'd have to plan out the length of the base plunger, die and ejector rod to know where this mid point would be located.

o How do you adjust the weight of the core? Do you adjust the height of the die or where the ejector rod "locks"?

Again if using a reloading press, you could adjust the die body (the base plunger in the ram is a fixed known) and also the ejector stop.

o What step did you need the mill for?

To cut the slots for the handles.

If you have any additional tricks/thoughts, I would appreciate hearing them...

Draw it out on paper first :-)

Thanks again for the write up!

John

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

EMC45
12-22-2007, 05:54 PM
Show Off!!:-D Very fine work Sir! You are an accomplished machinist as evidenced by your handiwork! I have thought to do the same thing for a core mold, but alas, no machining/mill/lathe skills. I used to run a pretty mean waterjet and hidef plasma CNC machine though:-D

GLL
12-23-2007, 11:15 PM
I can now see why the heavy box I sent you sat on your shop floor for a few days ! ;) ;)

VERY pretty !

Jerry

Buckshot
12-24-2007, 01:27 AM
I can now see why the heavy box I sent you sat on your shop floor for a few days ! ;) ;)

VERY pretty !

Jerry

....................Perceptive man that you are :-) HA!

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

toecutter
12-27-2007, 04:48 AM
Nice write up!

One thing I'm still struggling with currently is what the best way to actually make the bullet forming die is. Thus far I have gotten OK results just boring and polishing a tube, and then carefully boring a nose punch with the ogive and a hollow base punch. While it works, and gives me something more resembling a hollow-base SWC, I would like to make more of a standard 1.5-2e nose shape. When it comes to cutting out the void for the inside of the die do you use a shaped ream? or some other technique I'm not familiar with. (of course this is followed by finish polishing).

Any help would be much appreciated!

Buckshot
12-28-2007, 06:30 AM
Nice write up!

One thing I'm still struggling with currently is what the best way to actually make the bullet forming die is. Thus far I have gotten OK results just boring and polishing a tube, and then carefully boring a nose punch with the ogive and a hollow base punch. While it works, and gives me something more resembling a hollow-base SWC, I would like to make more of a standard 1.5-2e nose shape. When it comes to cutting out the void for the inside of the die do you use a shaped ream? or some other technique I'm not familiar with. (of course this is followed by finish polishing).

Any help would be much appreciated!

..............I use high speed steel drill blanks. You can also buy HSS cylindrical tool bits. You then grind a portion in half like a 'D' reamer the length of the feature (usually the nose) you want.

http://www.fototime.com/129DCEECEED65CD/standard.jpg

The above is a (rather poor) photo of one getting ready to go into a die body for swaging 58 caliber Minie' boolits.

After you have it ground in half, you then grind the radius into it. Then you grind in the relief's and clearances. Once that is done you stone it like a regular lathe bit but with no back rake as you do not want it digging in. These cutters are called spoons. Grinding is very tedius for me as I don't have, nor can I afford a specialty grinder of most any description. I merely use a bench grinder, and take my time.

For a short boolit like a pistol slug you could grind in the complete profile with the lube grooves and GC shank, say. That is, if for a mould as a Swage die doing lube grooves is a whole nuther kettle of fish.

I grind the spoon so the heel will actually cut the cylindrical body, very much like a boring bar. As the radius begins to cut, you have to feed very slowly. You can visualize that as the tool advances more and more of the spoon cuts. Naturally you want to step drill out the majority of the material.

http://www.fototime.com/13A02A26BD7AC9F/standard.jpg

My late does not have a DRO, so I've set up a system to use a dial indicator to read on the carriage for longfeeding, but depend on the cross slide dial for cross feeding.

http://www.fototime.com/CFC43FFAA50298D/standard.jpg

This is the spoon after making a cut. As you can see on the spoon and on the lathe bed behind it the swarf is fine. When making finishing cuts to bring it to final size before polishing, the metal is so fine it's like mud, or silt in the oil.

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

garandsrus
12-28-2007, 10:25 AM
Buckshot,

How do you polish the cavity?

Also, how do you polish the die ejectors you make for Lyman/RCBS dies?

I know that you use a set of brass barrel laps to polish the inside of a die.

Thanks,
John

Buckshot
12-28-2007, 08:19 PM
Buckshot,

How do you polish the cavity?

I use silicone carbide paper and WD40. You can use kerosene, lamp oil or even diesel. The paper goes on a split steel dowel. Now this is going to sound REALLY dumb, but it works. For a 'final form' die as above to form a radiused nose I cut the paper wide enough so there is about 1/2 to maybe 3/4" sticking out beyond the end of the dowel. This is then kind of loosely twisted to reduce it's diameter and then it's inserted into the spinning die. The paper (wetted with WD40) is pliable enough to readily form to the shape.

You don't have to do a lot of polishing BTW. The polishing you DO have to do depends upon the finish you left when you got done using the form tool. Two major reasons my dies are so large in OD (1.312") versus say Richard Corbins @ 1" is One: They're made of 12L14 steel, and Two: They're not heat treated. 12L14 is a leaded steel and it machines like cheese. With a good sharp tool you can create a surface that's almost like a mirror.

Also, how do you polish the die ejectors you make for Lyman/RCBS dies?

I don't. If you use a good free machining steel, in this case W-1 it will yeild a very nice surface finish just as it is. You MIGHT have to use some paper to take off the last tenth if your final cut didn't make it, or you're chicken to take a ten thousandth with the tool bit :-). If you use something like common low carbon 1018 you WILL have to polish as it's gummy and tends toward a rougher finish. Doesn't seem to matter how much side and back rake you put on the tool it's still rather poor.

Something else. You don't have to have a mirror finish on the ejector pin. A few small shallow rings on it won't make any difference. In fact it may even help as a very thin film of lube can gather there. So long as the body of the pin fits to a thousandth or less, these imperfections amount to nothing. I don't ship them that way because people expect to see a uniform bright surface. It's also just a sign of carefull work. But when you come right down to it, what works and expected appearances can be 2 different things

I know that you use a set of brass barrel laps to polish the inside of a die.

Thanks,
John

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

longbow
12-29-2007, 03:56 AM
Good stuff Buckshot - a practical man all the way!

Excellent info.

Longbow

miestro_jerry
12-29-2007, 05:38 PM
Wow, amazing! I will have to see what I can do with my machine shop to make something like this.

Thanks,

Jerry

JBMauser
12-30-2007, 01:19 AM
I have a question, I bought some AL stock that I have to take to a friends mill to true up. I was going to drill the holes then buy a reamer to true them round. is that good enough, did you bore them to make them larger? Will a reamer work as well? I only have a Unimat lathe with a 3 jaw, 3in. swing so can't swing the blocks into a boring bar. JB

Buckshot
12-30-2007, 03:25 AM
................toecutter, below are a couple photo's:

http://www.fototime.com/A7FCD0C7C32B712/standard.jpg

These are a bunch of internal form tools. The 5 on the left would be considered spoons, having to do with thier shape. The 4 on the left are for forming noses either in moulds or swage dies.

http://www.fototime.com/FBC4A50229228CB/standard.jpg

A closeup of one. As you can see, there is no side or backrake, and it is well stoned. The cutting edge on the left will shave hairs on your arm even though it is a relatively shallow angle. There is relief below the cutting edge. It's a fine balancing act as to how much relief as you don't want to weaken the edge, but at the same time it MUST be keen. You can picture in your mind that without siderake even taking light cuts it is not truly slicing through the metal. One thing about it, it WILL let you know when it needs to be sharpened in the form of chatter.

...............JBMauser, You didn't say so Im guessing you are taking about a mould? If so, a reamed finish should suffice as that is what a cherried cavity is after all. However with a chucking or machine reamer they cut on the front bevel only. Aluminum wants a lot of SPM, and be sure to use some WD40 as it's an excellent lube for cutting AL.

On my core mould I wanted an exact size and rather then buying a reamer to give me that, I bored. As I noted in the description, it's a bored finish.

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

JBMauser
12-31-2007, 09:35 AM
Thanks Buckshot, yes my goal is to build a .45 cal core mould. your information is of great value to me. your comment about drawing out a plan is of great value. I need to go out and buy a set of handles for a 4 hole so I can figure out the ID and pin placement. How much under swage dia. did you build your core .dia? JB

Buckshot
01-01-2008, 04:16 AM
.............The target ID for the final form die was .373" and maybe a couple tenths if I had to, to get the polish. The core bleed die had a target ID of .370" Max. The core mould was bored to .367" and pure lead drops about .3657 or so. I wanted to leave a bit of extra room between it and the core bleed die in case I wanted to use a harder alloy.

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