Broken bullet

[joeb33050]

The bullet was just sitting there amongst the other 30 BR cartridges, an RCBS 165 Sil bullet, gift from buck1. Broke right above the GC, no stress at all! Just when I think I've seen everything.
joe b.

[Echo]

Must have been cast from a REALLY hard alloy...

[Larry Gibson]

That is very interesting. Would be nice to know the alloy and any heat treating done. I've not seen that before either!

Larry Gibson

[sargenv]

I knew someone who was sold Monotype for Linotype one time and he had something similar happen to him with a 38 super cartridge. Same kind of crystalline structure.

[Ricochet]

Somebody once posted about his boolits snapping cleanly off at the case mouth when crimped. Somebody else said he'd had them break off that way when dropped. Someone a day or two ago posted about his Mosin boolits "exploding" at 2100 FPS. That has to be brittle alloy, too.

[1Shirt]

I have had a few drop on concrete and break. They were high in antimony and very brittle. I remelted the batch and added a considerable qty of pure(if there is such a thing anymore) lead and a percentage of tin. They were 30's. Probably would be ok as 225's loaded for varm.
1Shirt!:coffee:

[454PB]

Looks like linotype from the very crystaline structure. I've broken rifle boolits in a vice. Clamp down on the base and you can snap them right off with your fingers.

[3006guns]

You guys are missing the obvious..........you're out in the field and suddenly find yourself in need of a wadcutter................:mrgreen:

[garandsrus]

I had a few break when seating the boolit also. The alloy was somewhere between Monotype and Foundrytype.

I was testing some 311291's to see how the alloy would shoot without mixing with anything else. I still have a few left. I was able to put a pair of pliers on the top and bottom of the boolit and break it apart. It looks just like the boolit above. :)

John

[jhrosier]

I cast some boolits from mostly-monotype alloy last year and had one break when dropped.
I put one in my bench vice by the nose and found that it could be broken by a fairly light tap with a screwdriver handle.
Aside from being a waste of a very hard to replace commodity, I had to question the safety issue.
What would happen to my prized rifle if the nose of a boolit snapped off when chambering a round, and later migrated a ways down the bore?:violin:

I don't cast with much over 4% antimony even for rifles anymore.
There just isn't much call for armor piercing cast boolits.[smilie=l:

Jack

[Boerrancher]

I don't cast with much over 4% antimony even for rifles anymore.
There just isn't much call for armor piercing cast boolits.[smilie=l:

Jack


Jack,

I learned years ago that harder is not always better. I shoot a 50/50 of range scrap from J words, and WWs. It is a fairly soft alloy truth be told, not sure what the hardness is but I really don't care. It holds together well and shoots good up through 2500 fps when gaschecked, and sized properly, along with a good aplication of the proper lube. I get good expantion on fur, and no leading in the bore.

I went through that phase of having to have "armour piercing" cast boolits, and durring that phase I scrubbed more lead out of my bores than I think I actually shot. Then I realize that the boolit only needed to be hard enough to prevent it from jumpping the riflings on fireing, no more no less.

Best wishes from the Boer Ranch,

Joe

[cbrick]

Joe, Foundry type (23% antimony) or Monotype (19% antimony). Even Linotype at 12% antimony is too much for expansion on game and far too much antimony for steel targets.

NO armor Piercing rounds with high antimony boolits, an exact opposite actually, even Linotype boolits shatter like a piece of glass on steel targets imparting little of their energy (momentum) onto the target.

Rick

[jhalcott]

When I worked in the steel mill I got some "lead" alloy material. It melted easy and poured perfect shiny bullets. Sice I didn't know the alloy , I decided to shoot some in my .44mag for practice. I missed a couple shots and asked a friend to spot my hits on the 50 yard bank. He said "ONE hit under the chicken and the other hit at the end of the row!" That was the first shot! 3 feet of spread! I shot at the pigs at 100 yards and knocked 1 over AND missed the 3rd,going between it's legs. Those were the hardest bullets I ever cast. It took a while but I got the "lead out of the barrel after a week of cleaning. I tested the BHN of the bullets at work, it was near 45 as I recall. Some kind of bearing babbit i believe.
And yes they would ring if dropped. When crimped too hard they often broke at the stress point.

[Bret4207]

That's an example of one of the reasons I don;t care for the super hard alloys and even more so of heat treating same. This one broke off clean. Whats to say one or might not crack during seating and fly wild when shot. Just one more problem you won't have by staying with WW alloy except for the odd gun requiring an exotic alloy.

[cbrick]

That's an example of one of the reasons I don;t care for the super hard alloys and even more so of heat treating same.

That's a misconception Bret,

Antimony is used in the metals industry to harden (strengthen) lead alloys and is an extremely brittle metal. In bullet alloy it also "hardens" the alloy and it also makes the bullets quite brittle as Joe's photo shows. In the manufacture of lead/acid battery grids the metals industry keeps the antimony below 6% because of the brittleness. The metals industry adds arsenic and then quenches lead/antimony alloys for further strengthening rather than adding additional antimony because of the brittleness of the additional antimony.

Lead does not respond to heat treating like steel, when steel is heat treated it becomes more brittle and it is a surface hardening. When lead/antimony alloy is heat treated it hardens all the way through and adds “no additional brittleness” above its initial antimony percentage. Arsenic is a catalyst that greatly enhances the level of hardening well above what the percentage of brittle antimony would suggest. There are several other elements besides arsenic which have the same effect but arsenic is the most common in the metals industry.

The misconception that heat treating your lead/antimony bullet alloy will make them more brittle is simply not true; this “old wives tale” probably comes from the common knowledge that steel becomes brittle so . . . lead must also. It is true that oven HT (up to 30 BHN) or even simple water quenching from the mould (about 18 BHN) can easily make your lead/antimony/arsenic bullets much harder than needed for your particular application but not more brittle. Too hard is responsible for far more leading problems than is too soft, too hard and brittle are two very different things in lead alloys.

I stopped using lino for shooting steel targets because of its 12% antimony, 12% is A LOT and bullets with this much antimony shatter like glass on steel targets . . that's "brittle". Joe’s photo shows the result of adding just 7% more antimony as in Monotype at 19% or Foundry Type at 23%.

Hope this helps.

Rick

[Glen]

Rick --

I agree with almost everything you wrote. One minor correction however -- when steel is heat treated it is through hardened, not surface hardened.

The surface hardening comes from case hardening where the mild steel is heated in a "bath" of carbon, so the only part that gets hardened is the surface where the carbon enters the alloy (this is also where case coloring comes from).

For modern steel alloys (e.g. 440C), the carbon is already in the alloy so the heat treatment can harden all of the alloy.

[cbrick]

Thanks Glen, learn something new everyday. :drinks:

I was thinking of heat treating steel as heating red hot and quenching in oil (hhmmm, carbon huh :roll:).

Rick

[BABore]

Rick --

I agree with almost everything you wrote. One minor correction however -- when steel is heat treated it is through hardened, not surface hardened.

The surface hardening comes from case hardening where the mild steel is heated in a "bath" of carbon, so the only part that gets hardened is the surface where the carbon enters the alloy (this is also where case coloring comes from).

For modern steel alloys (e.g. 440C), the carbon is already in the alloy so the heat treatment can harden all of the alloy.


Ditto on the steel thing.

Also, it is possible to harden the outside of a lead alloy and leave the interior progressively softer. It requires a specific temperature for the alloy to harden. This is some of the reason why some will get a hardness difference between WD and OHT boolits. If you get the boolit JUST barely above the critical temperature, the outside is rapidly cooled upon quenching whereas the interior temperature has dropped below the critical point before it is rapidly cooled. This is easily tested by using both a hardness tester and expansion media. A control batch, OHT'd at just below the slump point, is used for the full hard boolit. Other batches, OHT'd at progressively lower temps, are compared to this.

[felix]

Brittle boolits will break like the picture(s) shown at the junction of the gascheck when heat treated with the gascheck already applied and crimped. Moral: heat treat before applying gaschecks, or test a few without checks first. Best to check a boolit after final heat treatment. ... felix

[cbrick]

Felix,

Over the years I've found very little to disagree with you on, here is an exception. Heat treating lead/antimony alloy does not increase the brittleness of the alloy, at least not according to the metals industry reports I've read. Adding additional antimony certainly does, heat treating does not.

Rick

[felix]

True, heat treating does not increase the brittleness that is already there. How much is there is the problem, and when the expansion difference between the antimony and copper is sufficient a broken joint will obviously occur. This does not mean the joint was not there immediately after checking, but the implication is that the crack is not seen. A good heads-up, Cbrick. ... felix

[Bret4207]

That's a misconception Bret,

Antimony is used in the metals industry to harden (strengthen) lead alloys and is an extremely brittle metal. In bullet alloy it also "hardens" the alloy and it also makes the bullets quite brittle as Joe's photo shows. In the manufacture of lead/acid battery grids the metals industry keeps the antimony below 6% because of the brittleness. The metals industry adds arsenic and then quenches lead/antimony alloys for further strengthening rather than adding additional antimony because of the brittleness of the additional antimony.

Lead does not respond to heat treating like steel, when steel is heat treated it becomes more brittle and it is a surface hardening. When lead/antimony alloy is heat treated it hardens all the way through and adds “no additional brittleness” above its initial antimony percentage. Arsenic is a catalyst that greatly enhances the level of hardening well above what the percentage of brittle antimony would suggest. There are several other elements besides arsenic which have the same effect but arsenic is the most common in the metals industry.

The misconception that heat treating your lead/antimony bullet alloy will make them more brittle is simply not true; this “old wives tale” probably comes from the common knowledge that steel becomes brittle so . . . lead must also. It is true that oven HT (up to 30 BHN) or even simple water quenching from the mould (about 18 BHN) can easily make your lead/antimony/arsenic bullets much harder than needed for your particular application but not more brittle. Too hard is responsible for far more leading problems than is too soft, too hard and brittle are two very different things in lead alloys.

I stopped using lino for shooting steel targets because of its 12% antimony, 12% is A LOT and bullets with this much antimony shatter like glass on steel targets . . that's "brittle". Joe’s photo shows the result of adding just 7% more antimony as in Monotype at 19% or Foundry Type at 23%.

Hope this helps.

Rick

After reading what I wrote and what you wrote I agree that I phrased that poorly. I'm in agreement with what you say and hadn't really thought of it in the clear way you put it. Thanks for making it clear.:drinks:

[jhrosier]

....too hard and brittle are two very different things in lead alloys.....

Good point! Thanks for bringing that up.
It is easy to get sidetracked when dealing with all of the variables that affect both casting and handloading.

Some days I yearn for the time when I didn't have to think about all of this stuff.:???:
Problem is, it was so long ago that I don't remember what I was thinking of......

Jack

[BABore]

Below is a picture and info on a commercial cast boolit that I used on a bison cow. Broadside shot at 66 yards. The boolit nose broke off at the crimp groove and the two halves were found together just under the hide. There was a little seperation between them when found with tissue embedded into the front of the rear section. I believe they had started to seperate after the on-side rib was broke and luckily just traveled together. I believe this to be the case since penetration was limited to just the 18-20 thickness of the bison with only one rib penetrated and one grlanced off of. The maker claims a 6% antimony level and heat treated hardness of 23 bhn. I believe the alloy to be 92-6-2. Upon additional investigation, I found that my overzealous use of a Hornady crimp die to be alot of the cause. The Hornady 480/475 die set comes with a 4th crimp die that sizes and contains the case as it roll crimps. You can pretty much pinch a boolit nose right off while never buckling a case. They tend to size cast boolits down a bit and loosen neck tension to boot. The Lee pistol FCD does similar deeds. I discussed the problem with CPB and found that I was not alone on this as he had a bunch of other customers with identical stories. Mainly die related, but alloy did play its part here. This boolit problem was what led me into casting my own.

A year later I took another cow with a OHTWW boolit of the same weight. It had approximately 4% antimony and was 28 bhn. The shot was quartering forward, almost straight on, at 50 yards. I placed the boolit directly on the front leg, just above the knuckle. The boolit put a 1/2" hole through the leg, broke a rib, went through the heart, broke the last off-side rib and deflected rearward, and ended up in the rear hind a couple inches. Total penetration was 48 inches and retained weight was 93%. A huge difference from the year prior and made me glad to be a boolit caster. Having learned through those experiences, and many others, I try to limit the antimony content to as little as possible and still have a alloy that will HT. This is one of the main reasons I use primarily 50/50 WW-Pb and OHT it. With 2% or so antimony and 22 bhn, it's tough and malleable enough to make excellent hunting boolits.