Hollow Point Conversion?

[dk17hmr]

How is this done?

I have read about people converting there molds from the orginal to cast hollow points, I am interested how is it done?

DK

[GLL]

I am sure Buckshot will be here shortly to refer you to some of his previous posts on this subject ! He does outstanding work and I recommend you contact him about HP conversions.

Jerry

http://www.fototime.com/BD88AD7A19EE4B9/standard.jpg

[Glen]

There are a number of ways that it can be done -- some better suited to certain mould types than others. The key issue here is getting the HP channel drilled on the cavity's axis. I do almost all of my conversions on single cavity Lyman/Ideal mould blocks. My preferred method is to take a piece of 1/2" aluminum round stock and turn a mandrel that fits snugly in the mould cavity, then clamp the blocks onto the mandrel, then drill the HP channel from the tailstock. After that's done, turning the pin and installing the mounting hardware is straightforward.

PS -- Jerry, that is a beautiful HP mould! Care to tell us about it?

[GLL]

Glen:

It is a Lyman 429421 that Buckshot converted for me (along with several others).

Jerry

[Glen]

Cavity diameter and depth?

[GLL]

Glen:

The pins on Buckshot conversions are completely interchangeable and depth can be adjusted as well. He can grind whatever diameter you might want and even provide an extra pin to make the mould produce the original bullet without the HP. Great design ! :)

Jerry

[Baron von Trollwhack]

Mr. Buckshot converted my old 515141 to make a 50 caliber "Gould " bullet for me. It works wonderfully in the 50-90. Regards, BvT

[Buckshot]

This is how I do it:

http://www.fototime.com/2235C21F3A083BE/standard.jpghttp://www.fototime.com/EC6E32186093ED1/standard.jpg

You set up the blocks in a 4 jaw chuck, and indicate the cavity to run true. Or you can use a precision vise on a faceplate (right), or by fixtureing them with angle plates to the faceplate. Or maybe even a dedicated fixture of some kind.

http://www.fototime.com/4E82C710D2AEAC9/standard.jpg

This is a Lyman 4 cavity being indicated. Due to it's length and the OD of the chuck, 2 of the jaws have to be reversed. If they weren't when they were cranked out they'd smack the lathe bed. The black ring around the cavity is so the idjit doing the work :-) will remember which bleeding hole to drill into!

http://www.fototime.com/4F570981026E8CC/standard.jpg

Actually a step is missing as first you use (or I do) a centerdrill to enter the cavity and start the hole. They're short and very stiff and drill exactly on axis. In the photo the hole is about to be drilled through. The drill bit can be that long as in this case it has a reduced nose which fit the starter hole the centerdrill made. Otherwise it would be too long and flexible and might wander. Doesn't look lke it but that IS the 4 cavity spinning.

The first time I drilled a set of blocks I was scared to death, HA! I checked, rechecked and triple checked and still found it REAL hard to mash the green button. After I did it and found it was fine I was pretty much useless the rest of the day.

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

This is what you end up with. I make the handle spindles from 1/2" steel. These are made up ahead of time in a batch from a 3' piece of 1018 HR. I use the shank from the drill bit that drilled the hole to make the HP pins. The drills are all aviation extension drill reamers that are 6 to 8" long. I got about 15 lbs of various sizes off E-Bay last year and the shipping cost more then the bits.

Various manufacturers use different meants to hold the HP assembly in the mould. I use precision stainless shoulder screws that are 1/8" under the head. They ain't cheap but they're excellent to work with. The spindle when made has a 1/2" OD for 1/8" and this goes under the shoulder screw to hold it it place. Then the spindle is reduced from 1/2" to 3/8" for about .600".

This supplies some beef for the HP pin retainer screw threads. The sockethead screw is threaded 4-48. Beyond the 3/8" the spindle is again reduced to .250" for the balance of it's length. This is what the knob is pressed onto. The drill bit used to drill the mould blocks is also used to drill the hole in the spindle for the HP pin. Since most HP pins are smaller then the .250" OD, I can deep drill into the tail of the spindle and so have a HP pin you can move in or out as the mood strikes.

There are a couple holes to be drilled and threaded and some detail items, but that is about it.

The setup is what takes the time, it has to be right or you can trash a mould. I no longer need 3 beers and 4 cigarettes before I can work up the courage to hit the green button. I do still double check everything beforehand though.

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

[Glen]

Nice work Buckshot! I've done the 4-jaw chuck route before, but I have run into problems with the fact that the axis of many Lyman cavities does not run parallel with the outer walls of the mould, so that when I dial indicated off of the mouth of the mould, the nose of the cavity was not on the lathe's axis (unfortunately, I did not discover this fact until after I had drilled the hole). A friend of mine (Rob Applegate) does it this way, and very carefully shims the mould blocks in the 4-jaw chuck to get everything coaxial, and he turns out some beautiful HP moulds. With the machine and tooling that I have to work with, I find the mandrel route to be straightforward and easy, and it turns out a first-rate HP mould (but I don't think it would be very well-suited for the Lyman 4-cavity you show above! I use a different method for those).

Some pictures might help convey my meaning. The first shows a picture of 1/2" aluminum round stock turned to fit a Lyman/Ideal 452460, and the "dog" that I made out of a piece of scrap aluminum, just to make sure that the mould didn't slip on the mandrel as I was drilling the HP channel.

The second photo shows the mould clamped in place, using a garden variety hose clamp, and ready to drill using the tailstock. The sprue plate stop pin goes in the "mouth" of the dog to eliminate any possibility of slippage (unlikely with a snug fit, but I use the dog anyway).

The third photo shows the drilled mould, along with the rough-turned HP pin and the rough-cut knob for the pin.

[6pt-sika]

Buckshot I have a Lyman #403169 two cavity . I would like to convert one of the cavitys but also have it so I can still use it as a two cavity FP mold as well . I have one of the Lyman #457122 HP molds and would like to use the HP pin from that mold.
Is this a relatively easy thing or not ? Feel free to email me with any pertinent info or questions.

Thanks Craig

:castmine:

[Buckshot]

Buckshot I have a Lyman #403169 two cavity . I would like to convert one of the cavitys but also have it so I can still use it as a two cavity FP mold as well . I have one of the Lyman #457122 HP molds and would like to use the HP pin from that mold.
Is this a relatively easy thing or not ? Feel free to email me with any pertinent info or questions.

Thanks Craig

:castmine:

PM sent.

Rick

[Buckshot]

...............Glen, "I've done the 4-jaw chuck route before, but I have run into problems with the fact that the axis of many Lyman cavities does not run parallel with the outer walls of the mould.............."

Yeah, I found that out early on.

http://www.fototime.com/2E52E1F832F7ACF/standard.jpg

I've run across a couple that had cavities off in 2 axis. I had to put them on a surface plate to finally get them figured out. The other issue with a 4 jaw is the 2 jaws stradling the parting line. Sometimes they can force the blocks to move laterally to each other. Also trying to shim blocks while in the 4 jaw can be a trying experience.

The presicion grinding vice on the faceplate is much easier to deal with as both law faces are parallel to .0002" and I gave up chasing tenths in mould cavities a long time ago :-).

That's a nifty setup you devised to get the cavity running true!

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