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jgh4445
05-21-2008, 07:48 AM
What would be your opinions of the differences in hardness of pure WW boolits that are water dropped and the ones just left to air cool? I've read of doing it both ways as well as heating them in an oven after they have cooled ( would you heat in an oven after water dropping or air cooling?). Which would be better for hunting?

jhrosier
05-21-2008, 08:38 AM
Water dropping has allowed me to increase the hardness of boolits cast from range scrap from about bnh10 to bnh15.
The range scrap is 80% shotgun slugs, muzzle loader bullets and jacketed bullets, with the rest being cast bullets.
Because the end hardness is largely dependent on the temperature of the boolit when it hits the water, variations in your casting technique or speed will change the hardness of the finished product.
It has not been a problem for me when casting pistol boolits but I am considering oven heat treating my rifle boolits to gain better control over the hardness from batch to batch.

Jack

Ricochet
05-21-2008, 09:48 AM
It's not really a matter of opinion. The stuff gets lots harder if you quench it and age it a bit. Try it.

Whether you need hard boolits is another matter, and opinion will certainly come into play there.

GabbyM
05-21-2008, 10:32 AM
Oven heat treat is the way to go IMHO. The only equipment I have is a couple of old rusty cookie sheets I keep in the shed. I don't heat the bullets to the point of sagging. 435* F for one hour then dump them in a dish pan full of cold water. I can do one thousand 44 caliber pistol bullets on two sheets.
I size them before heat treat then lube after. That's where the extra work comes in. Sizing first does two things. One it makes it so much easier to size. After treat they may be over 20 BHN and a 44 cal that hard takes a huge amount of pressure on the sizer lever to push through. Secondly you avoid work softening the lead after heat treat.

Water dropping before oven heat treat would do no good since the heat cycle in the oven would negate your effort of water dropping.

You can find a great article on heat treat here at the Los Angeles Silhouette Clubs site.
http://www.lasc.us/HeatTreat.htm

felix
05-21-2008, 10:49 AM
For the best accuracy, and this is required only for BR guns, water drop the boolits before oven treatment. After about a week of water dropping, then size the boolit (base first if lots of sizing will take place with a gascheck boolit) without lube or gascheck. Then, do an oven dealie. Wait a month or so for the boolits to equalize. Then, check and lube, and then wait a year or more before shooting. My seven year old WW+2%tin boolits will shoot a bonifide 1/2 inch at a hunnert using a BR gun on an unsteady, cartop rest. ... felix

475/480
05-21-2008, 11:11 AM
My WW alloy is BHN 14 when air cooled. If I water drop them they come out BHN 23 and as the mould gets hotter and hotter during the casting session the BHN goes up to 28 on the water dropped boolits.


Sean

BABore
05-21-2008, 11:33 AM
Yes, patients is a virtue when it comes to HTing boolits. You may get away with a couple days to a week of curing, but variance will rear its ugly head from time to time. It can make an otherwise accurate load look bad and you will have missed out.

There is no telling what your gun/cartridge will like for bullet hardness. Most will use velocity and pressure to dictate hardness, but it is not always so. Let the gun tell you. There are also many ways to get hardness, and hardness and alloy are different animals. Linotype has a hardness of approximately 22 Bhn as cast. 50/50 WW-Pb has the same hardness when heat treated. Straight WW's OHT will run 28-30+ Bhn. They can be drawn back through oven annealing to 22 Bhn. Three different alloys of the same hardness, yet they will all shoot and fragment/expand differently.

When I first started, I only used WW's. I shot them as cast (12-14 Bhn) or OHT'd (28-30 Bhn). As I got more learning, I would take OHTWW's and oven anneal them in 50 boolit batches, at incremental temperatures. I think I started at 250 F for one hour and turned the oven off, taking them out when cold. Each sucessive batch went in at a 25 F hotter anneal until boolits tested out to as cast hardness levels. After a couple weeks cure time, they were shot with my best load for that gun at the velocity I was looking for. With that knowledge you can then look at other alloys to get the hardness, toughness, and expansion qualities you need. Alloying WW's with pure lead can make a great hunting bullet at exactly the hardness your gun likes best.

Naphtali
05-21-2008, 11:46 AM
Gabby mentions "work softening the lead" via sizing. And sizing affects only a few thousandths. In large diameter bullets, say .458-inch and larger, how deeply does heat treat penetrate?

felix
05-21-2008, 11:58 AM
The distance hardness is penetrated is proportional to the temperature gradient between 425 and 300 degrees in the amount of time that it happens. Because this slope is a non-linear one, the hardness obtained will also follow the same pattern. ... felix

jeff223
05-21-2008, 12:17 PM
does anyone know how fast you can push an air cooled gas checked boolit made out of straight wheel weight lead and have no leading?i have always water quenched my wheel weight lead boolits and i can push them as fast as i want without leading.i would think the softer air cooled boolit would be better for hunting over the harder one if the accuracy stayed the same

felix
05-21-2008, 12:30 PM
Jeff, in a hunting situation, I would worry zilch about leading. Shoot to kill on the very first shot!!! In practice, see what you can get away with in terms of velocity/yardage/pieplatetarget with ONLY ONE SHOT out of a cold barrel. ... felix

jwp475
05-21-2008, 12:32 PM
Veral Smith told me back in the mid 80s that pure wheel wieghts dropped from the mould into water would be 22 to 24 on the Brinneil scale.

The "Boolit Bub"

runfiverun
05-21-2008, 09:06 PM
jeff be aware that the first shot from a cold bbl may land in a different spot than your warmed
bbl group.

jwp nowdays they are more like 18 bhn. [ lower antimony content]

the oven treat is also more consistent bhn wise, but a 50/50 mix w/quenched is easier to make, and certainly enough to hunt with.

the de-temper in the oven does require some testing but is probably the best boolit.