Alloying Boolits... For harder castings...

[inuhbad]

I have plenty of Wheel Weights now, and I was wondering how I can get them harder... Like in the 20-25 hardness range.

I heard some people here saying to add a certain type of shott to add more tin???
Is there a way of shredding Tin Cans & smelting them to add tin???

I intend to smelt the alloy, make Ingots, and then use the hard-cast for faster-moving rifle boolits around 2400 fps if I can! I want to cast them with the harder alloy (Wheel Weights w/ added Tin), and then I'll size them (without lube), and then heat-treat them in an older toaster oven around 425 to 475 degrees (would that temp work okay?). They'll be in the oven about 30 minutes or so, and I was thinking if I then take them straight out of the oven, and drop them into a bucket of !COLD! water (with padding inside of course), that I might be able to increase their hardness a fair bit...

So, here are my questions:
1.) What's the name of the type of shotgun Shott I could add to my Wheel Weights to get a harder alloy?
2.) Would it be cheaper/easier to just melt down tin cans in sizable quantity???
3.) What ratio / percentage of Tin / hard shotgun shott should I add to the wheel weights?
4.) Would a temperature between 425 to 475 work? I'm not sure if my toaster oven could get much hotter...
5.) Would heating them at that temp range for half an hour & dunking them in cold water harden them? Or should I keep them in longer?
6.) Do you know if the typical .30 Caliber Gas Checks available from Hornady will fit a .312" boolit???
7.) What are your suggestions to get your bullets up to a 20-25 BHN range?

Can anybody else share with me THEIR method of hardening your bullets (starting with wheel weights)???

I'd really appreciate learning more about alloying to ideal hardness!

-inuhbad

PS. This is likely for .312" Bullets (7.62x39mm) for use in some AK-47's!

[docone31]

Drop em in water when you cast. They harden right up.

[Ole]

I water drop my straight WW SKS bullets and a friend has tested them @ 22-24 on the BHN scale.

[Ole]

Yes, the std 30 caliber gas checks should fit

I air cool my .44 bullets then heat treat them in an old toaster oven. Do not trust the temperature dial that is on the oven. Use a separate thermometer. I set my temp just under 400 and it cycles on around 430F and off around 445-450F.

[KYCaster]

Not in the order you asked, but....

Tin cans don't contain any Tin. At one time steel cans were plated with Tin to prevent corrosion, that's where the name came from...that's no longer done. The most common sourse of Tin is solder.

30 caliber gas checks will work fine on .312 boolits.

Magnum shot is added for the Arsenic content. The Arsenic is desireable in very small ammounts to enhance the ability to heat treat the alloy. In the small ammounts used it doesn't add any hardness on its own without heat treating. Wheel weights contain enough Arsenic for heat treating without adding it from another source.

Tin alone will not substantially change the hardness of wheel weight alloy. It is added mainly to enhance mold "fill out". (sharper detail rather than rounded corners) Tin exceeding 2% total doesn't help anything.

I haven't done any heat treating, so I can't tell you much about it. The Lyman Cast Bullet Handbook has a very detailed decription of the process and a search here will turn up lots of info.

I understand that 20 BHN is fairly easy to attain with wheel weight alloy. 425* seems to be the temp. most often cited by the guys who do it. I would suggest trying a few at a time at various temps to see where your alloy starts to slump (deform from the heat) and use a temp slightly lower than that. Most of the descriptions I've seen say that the time from the oven to the water should be as short as possible for the best results.

I'm sure somebody with experience will jump in here with more info.

HTH
Jerry

[snaggdit]

+1 on what KYCaster said. This jives with what I have come to learn as well. I water drop WW for my SKS and as Ole said, hang on, I'll check again. OK, my lee hardness tester on 2 month old Lee .313 150gr 2R says 24.8bhn. I see on my container they tested 19.3 a few days after casting/water dropping. This is true, since from what I have come to learn they reach full hardness in a few weeks. Since I live in the north, I have the advantage of walking outside in the winter and scooping snow into my gallon pail and adding some water. The hot boolits drop right through the slush and harden well. I also tried some 6:1 WW/Lino that was 24.8 a few days after casting. Today (1 month old) they are at 27.2bhn. For the speeds my SKS is loaded for, this is probably overkill and I will stick with WW in the future. Now for my 30-06, this is probably good (but I use an Lee 180gr 1R .309).

[AZ-Stew]

Please see my thread: http://castboolits.gunloads.com/showthread.php?t=42870 on using a toaster oven for heat treating.

Plus 1 on the Magnum shot for arsenic content if you want maximum hardness. KYCaster also covered your questions regarding alloying and "tin" cans, which aren't.

That having been said, what firearms are you casting for? Most revolvers and auto pistols don't need "hard" boolits, and may actually be more accurate with relatively soft boolits. With rifles, it seems that the smaller the bore, generally, the harder the boolit required to get good accuracy. In a LARGE number of applications, as-cast (air cooled) wheel weights and plain-based (non-gas check) boolit designs are perfectly adequate. When velocities exceed about 1,400 fps, gas checks and harder alloys are indicated.

Regards,

Stew

[inuhbad]

WOW! Thanks for the great advice, guys!!! I really appreciate it!!! :drinks:

I think I'll still add a little bit of Tin for the fill-out, and a little more magnum shot if it's not too expensive - just a small amount per pot of wheel weights to get a tiny bit of arsenic in there.

We'll see how the first alloy goes... I hope it all works out great!

It just started snowing here again for the 4th day in a row, so I don't think I'll get out to do much of any smelting/casting in the next few weeks.

Minnesnowta is a little 'quirky' like that with our weather. :sad:

Snaggdit, where in Northern Sconnie do you hail from? I think I'll try the bucket 'o snow & water idea...

AZ-Stew, once I get my ingots & alloys made up, I'll be casting for the following:
45 ACP 225 Grain LRN (Lyman Mold) - With plain old wheel weights - dropped in a bucket of cold water.
38Spl/357Mag 140 Grain LSW (Lyman Mold) - With plain old wheel weights - dropped in a bucket of cold water.
7.62x39mm .312 130gn - With Wheel Weights, A little Tin & Magnum Shot added & ice-water cooled. I want to try running these around 2400 to 2600 fps if I can! :)

Maybe in a year or so I'll get the .312-155grain Lee 6-Cav group buy mould so I'm hoping to get these heavier bullets 2200 to 2400 fps (if pressure/powder allows).

I'm also going to be casting pure lead cores for swaging into 22LR casings/jackets to make some .224 bullets later this year.

[selmerfan]

PM sent - we're fairly close to each other.

[snaggdit]

I think I'll still add a little bit of Tin for the fill-out, and a little more magnum shot if it's not too expensive - just a small amount per pot of wheel weights to get a tiny bit of arsenic in there.
Remember, WW already have a little bit, so you will be adding some more. Not really necessary, but won't hurt.


Snaggdit, where in Northern Sconnie do you hail from? I think I'll try the bucket 'o snow & water idea...

AZ-Stew, once I get my ingots & alloys made up, I'll be casting for the following:
45 ACP 225 Grain LRN (Lyman Mold) - With plain old wheel weights - dropped in a bucket of cold water.
38Spl/357Mag 140 Grain LSW (Lyman Mold) - With plain old wheel weights - dropped in a bucket of cold water.
7.62x39mm .312 130gn - With Wheel Weights, A little Tin & Magnum Shot added & ice-water cooled. I want to try running these around 2400 to 2600 fps if I can! :)

Maybe in a year or so I'll get the .312-155grain Lee 6-Cav group buy mould so I'm hoping to get these heavier bullets 2200 to 2400 fps (if pressure/powder allows).

I'm also going to be casting pure lead cores for swaging into 22LR casings/jackets to make some .224 bullets later this year.

The 45 is a slow round. 800-900fps. Don't even worry about hardening it. They work fine air cooled. 38/357 your call. Target loads are still fine air cooled, hot loads you might want to water drop.

I'm not too far away, PM sent.

[Bret4207]

WW alloy already had arsenic and other traces elements in it and tin. Until you find you NEED additional enriching I strongly suggest you fore go adding anything. Better fill out? You haven't even cast anything yet and you figure you need better fill out? Slow down, stop listening to whoever it is that's putting the garbage in your head and start at square one. Plain WW, flux them good and clean, get your mould really clean and get the alloy up to 750 or so. Then start casting at a good clip. The mould will soon come up to heat and you'll start getting good boolits. If they're frosty, so much the better. Barring mechanical issues, like burrs and grease in the cavities, it's a rare mould that needs additional tin, etc. to get good boolits.

I don't mean to be rude or nasty, but you're doing the same thing I see a lot of other noobies doing, you're over thinking this and making it far too complex. Learn to cast before you start worrying about exotic alloys and "hard" boolits and running things at 2400 fps. In fact, don;t worry aobut boolit "hardness", worry about fit because everything else follows fit.

[BABore]

My Michigan WW's, with the stick-ons sorted out, will WD or OHT to 28-30 bhn with no added anything. I cut them with 50% pure lead and still get 22 bhn. Try them out first before adding anything. They'll be plenty hard. If your WD'd boolits are substantially softer than OHT'd ones (435 F for 1 hr, then quenched), your probably not running your mold hot enough or taking too long to get them into the water.

[sheepdog]

The 45 is a slow round. 800-900fps. Don't even worry about hardening it. They work fine air cooled. 38/357 your call. Target loads are still fine air cooled, hot loads you might want to water drop.


+1 on this. Too hard is as bad as too soft. I'm new but from what I understand proper measuring and sizing is 9/10ths the war of leading.