HP Molds...Question For Buckshot???

[seagiant]

Hi Buckshot,
Hope you're doing well. . What I was wondering about is that there a quite a few of us here that own lathes and are probably what you would call hobby gunsmiths. I have an old Ideal 44 cal. Kieth type 250 gr. single cavity mold that I think would be perfect for turning into a hollow point. How hard would it be to explain the steps you use to turn a mold such as this with a lathe into a hollow point mold and also the stem that goes into the mold for making the cavity in the bullet? I think I could do this but would like some ideas on the procedure to have a good chance of success!
As always any help with this would be greatly appreciated! Thanks!




I am time grown old, creating world destruction set in motion
to annihilate the worlds;
even without you,all these warriors arrayed in hostile ranks
will cease to exist.

Therefore,arise and win glory!
Conquer your foes and fullfill your kingship!
They are already slain by me.
Be just my instrument, the archer at my side!



The Lord Sri Krishna to Prince Arjuna
Bagavad-Gita
4000 BC

[crazy mark]

Seagiant,
This ain't Buckshot but here's how I HP my moulds.
I use a 4 jaw chuck and dial in th cavity on my lathe. And I bore the hole the size I want for my HP pin. I use drill rod for the HP pin. I use 3/8" rod for the HP pin to go thru and a set screw to set the length of the HP pin. I use drawer knobs for the handle. I sometimes use an e-clip to do the pin to mould attachment. Other times I use the pin under the screw attachment. Either way works fine. You really need a HP mould to work from. Mark

[Buckshot]

................Seagiant, greetings. Saw your handle over on the Chaski board this evening. Marks' explaination is a variation of mine on construction proceedures. The basics are just that, basics and no way to really do it much differently.

You also have to accept something right up front with cherry cut cavities. That is that none are ever concentric with any outside flats on the blocks, nor are they co-axial with the parting seam of the 2 blocks. Ever.

First thing I do is to make sure the blocks are in good tight alignment. I then check to see what the largest centerdrill is that I can use inside the cavity for a pilot hole. The cavitiy's body may accept a #4 centerdrill yet the centerdrill's taper may interfer with nose features.

Next is to figure out the diameter of the HP pin. I have used drill rod, but now I use the actual drill bit shanks from the bits I've drilled the hole with. These are HSS and tougher to grind to shape and part off, but they fit the holes to a 'T'. Early on in my E-Bay career I was high bidder over several auctions for 5 lb lots of aviation extension drill bits. These are all 6-8" long and come in various number and fractional sizes, with 1/4 being about the largest. Many are drill/reamers and most are piloted. I have a ton of'em :-)

Then you chuck them up in a 4 jaw chuck. A couple things. The 2 jaws that bear on the opposing blocks can be cinched down tight. The 2 jaws spanning the seam on either end cannot, or they may cause the blocks to offset relative to each other. THey should just be snuggly in contact.

http://www.fototime.com/2235C21F3A083BE/standard.jpg

You need to eyeball the cavity in close enough so you can then insert a test indicator. Most of these read .050" or .025" and if the cavity is out more then that you can damage the TI. One reading to .0005" is all you need. Using one accurate to .0001" is lunacy. You'll never get the hole drilled because you'll be chasing partial thousandths all over.

I run the TI about midway into the cavity and run it on a lube groove or the nose, depending. Then I run in the centerdrill to start the hole. Back out and put in the drill bit. Shoot lube into the cavity ( I use regular cutting oil) and drill the hole.

http://www.fototime.com/36F87DBAD71E079/standard.jpg

I use a bit different handle assembly. The above is a poor photo, sorry. I use 1/2" drill rod for the handle. A flange 1/8" wide is left at 1/2" OD, then it's turned down to 3/8" for a distance of about a half inch and then it's reduced to 1/4" for the balance of it's length, and this is what the wooden knob is pressed on to.

The 1/2" diameter flange bears against the bottom of the blocks. The 4 jaw chuck comes off and a 1/4" 5C collet goes in the spindle nose to clamp onto the 1/4" length of the handle. I then use the same drill bit I used ot make the hole to drill into the handle for the HP pin. If the HP pin is small enough I can drill quite deeply into the handle part. This allows you to extend the HP pin in or out with quite a bit of latitude. Some you can extend the HP all the way to the base of the boolit!

The Lyman 311410 in the photo is just such a case. In the photo the end of the pin hasn't been ground to shape. Since this slug is a plain base, having a hole all the way through the slug isn't a good idea :-) . A GC design will allow the HP pin to touch the GC.

To retain the handle assembly against the blocks I use stainless precision shoulder screws as below:

http://www.fototime.com/{7C8C4CB6-7816-4E30-8820-10204F49D8D1}/picture.JPG

Again a rather poor photo. These have a short 8-32 threaded section, then a shoulder 1/8" wide and then the much larger OD of the head. The half inch diameter flange of the handle has a section ground out to so it will slip past the head of the screw, and it then turned under it. The HP pin inside the handle has a flat ground on it. A hole threaded 4-48 through the 3/8" portion of the handle accepts a sockethead screw which locks the HP pin in place.

A MUCH better photo can be seen here:

http://castboolits.gunloads.com/showthread.php?t=5645

Or here, down the thread aways:

http://castboolits.gunloads.com/showthread.php?t=5010

While I think it is a good positive method of locating everything, those shouldered screws are pretty danged expensive.

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

PS: The first couple times you do this, it's pretty darn scarey, and I'm not afraid to admit it! After getting it setup to drill I had to stop an have a smoke leaning against the workbench, all the whole staring at it. Then I had to go back and touch everything and do a kind of mental checklist a couple times. When I mashed the green button I could barely force myself to bring the tailstock up and stick the bit into the cavity. After it was done I was scared all over again, to take the blocks apart to look at what I'd done.

[seagiant]

Hi,
Well what can I say after that??? This has got to be the best people on the Internet! Bar none! Thank you,Gentleman that is just what I was looking for and to be honest I can see where I would of screwed the pooch as they used to say years ago. I was thinking all wrong on some things I can see now. Go figure!
Buckshot,thanks for answering my questions so well you no doubt saved me a mold! Take care Amigo!




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