Water dropping

[Half Dog]

I understand water dropping will increase the hardness of a bullet. Is it a surface hardness? Is there a curve that shows hardness reduction over time?

[44man]

It makes a boolit get hard faster then air cooled but seems to go deeper.
I water drop everything, even pure balls since it is easier then fooling with a towel on my small bench space. True it does nothing to them but I like the easy stuff.
I figure the hardness only needs to be a little deeper then rifling anyway so how far one hardens is not too important.

[mdi]

Interesting question. I would like to hear from someone who has sectioned a water dropped bullet and compared surface hardness with core hardness...:confused:

[williamwaco]

Don't know about internal hardness but over time they will soften.

[gwpercle]

It is a surface hardness, if the hardened boolit is sized , this cold works the surface and softens it back to about where you started. So if you do it, don't size them.

People have over rated the value of hard boolits. Proper fit trumps hardness any day.

All my handgun and most cast rifle boolets just get air cooled. Only if trying high velocity in rifle might I do a hardened boolit , but I size them, heat in an oven then quench in water. Lube with out further sizing.
Truth be known 98% of my shooting with cast is handled with air cooled boolits of the proper alloy and size.
Gary

[dragon813gt]

Is there a curve that shows hardness reduction over time?

It's alloy dependent: http://www.lasc.us/Fryxell_Book_Chapter_3_alloySelectionMetallurgy.ht m

If you haven't read of Fryxell's book I suggest you do.

[bangerjim]

Fit is King. Forget hardness today. In the old days, every emphasis was on Lyman #2 or Linotype for casting. Now we use that lino to mix with pure! And slug our barrels and cast and size accordingly. A hard boolit will actually lead easier than a softer one. (conditions will vary)

And you cannot cut a piece of WD lead without changing it's hardness by the cutting tool action. We are not dealing with martensitic and austenitic steels and their properties here. Lead has totally different metallurgical properties.

Ya drop your boolits in water, ya take yer chances. And the hardness shifts over time, so why bother trying to calculate it.

I mix all my alloys for pure air cooled hardness. If I need 18 for rifles, I mix it for 18. No guesswork, no voodoo water hardening. But I use 9-12 + PC for everything subsonic, so hardness is of really no concern to me anymore.....and many others on here.

The only way to have some control over it is to actually heat treat them by soaking at a predetermined higher temp for a certain time and then dunking them rapidly in a specific temp cold water. And then in 3-4 weeks, you may have some relatively controlled hardness boolits.

But why bother? Air cool them and shoot more!

And read the book listed above.

banger

[mdi]

I was just curious about how deep the "hardness" went. I just air cool my mystery metal cast bullets (last time I checked they ran about 13 BHN) and have no trouble shooting bullets that fit in my guns...

[bangerjim]

If the shoot OK........do as the mob says..........."FORGET ABOUT IT!"

[Yodogsandman]

http://www.lasc.us/HeatTreat.htm

[GLynn41]

wd causes the surface to harden much like a shell most of the interior does not change- dendrites harden differently because of the water temp- will not cure other problems such as fit etc- I have read you should size soon before the full hardness takes place at about 24 hours or so?--- I use with it with my 4'' Tarsus .41 mag with 230 Keith boolits ( may not be needed but it is ported) or 9"41GNR -- 225 grLFNGC at 1800fps-- when I do not use a cast HP

[JWFilips]

I Cast 50 % Pure+ 50% Clip on wheel weights & I also add 2% tin to this alloy: If I water drop for the smaller / faster calibers IE: .243 Win I get a BHN of 18 to 20 But as soon as they are removed from the water bath I size to my preference of .246" Then wait 3 weeks to shoot! They will then reach BHN 18 to 20

[Garyshome]

I water drop everything I cast. It allows me to examine them quickly, make adjustments to the pot/mold/check size........

[243winxb]

http://www.freepatentsonline.com/5464487.html Go to the bottom page at link. See "EXAMPLE"
hardness tested both at the surface and the core. These tests revealed that the hardness was essentially uniform throughout.

[Mal Paso]

I water drop everything supersonic. I size boolits down about .001" which is no where near the depth of rifling. I think WD helps control skidding in 44 Mag. Normal pressure is over 30K PSI and I've seen leading down one side of the lands from boolits stripping the rifling.

[outdoorfan]

I filed down the side of a bullet one time that was cast out of 50/50 ww/soft with 1% tin added. Water dropped it was right around 20 bhn on the exterior. As I filed down and kept checking hardness as I went, I discovered that it was still hard (around 20 bhn) all the way through.

45 2.1 has said that by waterdropping 50/50 alloy out of a mold that is not running too hot that he can get a hard shell and soft interior, so it must be possible.

[243winxb]

Mould to water is not the same as oven heat treating.

[tazman]

No it isn't. But if you only need a little extra that just grips the rifling under lower pressures(like 38 special) mould to water is enough to work great.

[44man]

No it isn't. But if you only need a little extra that just grips the rifling under lower pressures(like 38 special) mould to water is enough to work great.
My CO WW boolits have been shot to 55,000 from the .454 without skid. I use them in my .44, .475 and .500 JRH. Just water dropped. It works. I will load in a few days, never wait 3 weeks.

[outdoorfan]

Water-dropping 50/50 ww/soft to obtain 20 or so bhn has been no trick for me. Sometimes if a mold isn't dropping consistently, then the temperature at which the bullets fall out of the mold into the water can vary a good bit. Then oven heat-treating can be much better as far as getting uniform results. And, oven heat treating can be adjustable to whatever temperature and corresponding hardness level is trying to be achieved. But it is an extra step in the process, and for many simply isn't necessary.

[tazman]

My CO WW boolits have been shot to 55,000 from the .454 without skid. I use them in my .44, .475 and .500 JRH. Just water dropped. It works. I will load in a few days, never wait 3 weeks.

I agree with that. I only wait long enough so that I can't scratch them with my fingernail any more. Usually 2-3 days.
If I need to size them, I do it right away, within 24 hours. If I wait longer the hardness makes them difficult to size.

[Half Dog]

Ok. Lets see if I got this...I have a .453 mold and casting for a 45 ACP.

Cast the bullets
Water drop them
Size them
Let them harden and shrink (2 to 3 days)
Lube them
Shoot them

[tazman]

Ok. Lets see if I got this...I have a .453 mold and casting for a 45 ACP.

Cast the bullets
Water drop them
Size them
Let them harden and shrink (2 to 3 days)
Lube them
Shoot them


Exactly right, although I am not certain they will shrink. I never check mine after sizing so I don't really know.

[Aunegl]

I would eliminate the "let them harden and shrink" part myself.

[44man]

With antimony, tin, etc, they actually grow in size as they age.

[NuJudge]

Water dropping pure lead will get you nothing in increased hardness. I don't believe water dropping Lead/Tin will get you anything in increased hardness, as in the binary alloy the Tin atoms merely substitute them selves, here & there, for a Lead atom, which does not distort the lattice much or inhibit the passage of dislocations much at all.

Lead/Tin/Antimony can be much harder than Lead or Lead/Tin. The Ternary alloy forms lots of small inclusions dotted all over. There is an optimum size for these inclusions, and its on the small side. The faster you quench, the smaller the inclusions will be. Strangely, cold water does not quench significantly faster than room temperature water. Salt water does quench significantly faster than tap water: my Professors said it was because the salt inhibited water vapor bubble formation (but who wants salt on something they're going to put down their bore?).

There is a slower speed of quench at the center of a thick section, than at the outside. In the lab we used to quench thick sections of steel, cut them in half, polish away the disturbed area near the cut, and do hardness testing (bear in mind, steel has very different hardening mechanisms). A bullet is hardly a thick section, and it would not surprise me if there was not much of a hardness difference between the outside of a .44 bullet and the centerline.