Suitable alloy for use as a hollow point pin for bullet mould

I'm repairing a 257312 Lyman meehanite bullet mould. Used a mechanic's length LH 135 degree point drill to back out the snapped off HP pin retainer. Now its time to replace the hollow point pin that extends into the bullet cavity.

Aluminum is out: markedly different expansion rate, scratches easier, and bends easier. But molten lead does not stick to it at all. Pity...

This alloy must be able to take a fine finish. No 1018 CRS need apply. Temperatures will be in the range of 725-800 Fahrenheit.

My first guess is HHS drill blanks. Also considering TGP.

The HP hole is a teeny bit bigger than a #41 drill (0.096 in/2.438 mm). My small hole gauge set only goes down to 1/8"...

Reply to
Louis Ohland
Loading thread data ...

Have you tried stainless to see if it sticks to lead? With its layer of chromium oxide, I would guess not.

Reply to
Ed Huntress

High-alloy drill rod may not, either. Stainless may be cheaper.

Teeny bit bigger than 0.096"/2.44mm sounds like it's an either an even

0.1" or an even 2.5mm, depending on whether it's 'merican or furrin.
Reply to
Tim Wescott

Molten lead does stick to aluminum. A mild release agent is all that is required however. Candle smoke was one of the popular ones, but a lot of the jig and spinnerbait guys are using Franklin mold release. Looks like a spray on graphite powder.

Reply to
Bob La Londe

I'd try 303 stainless. I made a wedding band out of it. It polishes up very nice.

Reply to
Jim Stewart

Do you mean "Frankford Arsenal"? Good stuff, but used in a mold you as get slightly undersized boolits. I use a tiny smidge of Kroil as a mold release.

Reply to
Tom Gardner

I think I recall you're using Lee molds (aluminum). When you say a smidge, how do you apply it? Q-tip??? Does it have to "burn out" over a few bullets before they stop being wrinkled like oil does, or does it work from the get go? Do you have to reapply it during a casting session?

RWL

Reply to
GeoLane at PTD dot NET

Carbide rod.

Gunner

Whenever a Liberal utters the term "Common Sense approach"....grab your wallet, your ass, and your guns because the sombitch is about to do something damned nasty to all three of them.

Reply to
Gunner Asch

Sorry, Yes. Frankford Arsenal.

Reply to
Bob La Londe

My hollow point molds have mild steel pins, takes a good enough polish. Either smoke or cold blue them before use. Any polishing marks should go lengthwise. You don't need an exotic alloy, there's no strength involved here, the pin just takes up space and needs to come out easily. Just make sure you allow enough draft when you make the thing. I've made enough of them from hardware store hot-rolled shafting. If I were doing it now, wooden knobs would be a problem since my major supplier went out of business a few years ago. Factory jobbies have a hole drilled in knob+pin and a drive pin shot in from the side to hold the works together. Most of the time it works. Have had a few loosen up.

Stan

Reply to
stans4

In the grand tradition of starting out the most complex and rapidly working to the simplest method, the idea is to buy a #41 HSS drill blank, round the point, then mill a slight flat on one side. Then turn a collar that extends up into the wooden handle, this collar will have a set screw so I can lock in the pin.

After seeing the old style locking pin (uses pin on collar against pin in block, under the screw head), it looks like it will be a positive stop. The new system uses an e-clip where its difficult to see the opening when re-inserting the pin.

Reply to
Louis Ohland

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.