Brinell Testing?

[kappy]

How do you find out the Brinell hardness number of your bullets/lead/etc? I should add... without paying hundreds or thousands for the machines I've seen?

[oneokie]

There are many tools for the home hobbyist to use for testing BHN. Lee makes one, Redding/Saeco makes one, and our own member Gussy makes one (Cabin Tree).

[runfiverun]

lee is like 55 bucks.
saeco is around 100
cabine tree is about 150 [airc] and the better one.
you can do the known and unknown ball bearing and vise measurement,
or guesstimate it from pencils to staplers.

[dlviolin]

Kappy,
Search this forum for "hardness ball bearing" and you'll find a whole bunch of rigs for measuring hardness that you can make for nothing. It involves pressing a specific size ball bearing into the lead for 60 seconds and measuring the dimple size. Compare to a chart and you've got the hardness. Works like a champ.

[Bassleg]

I use a lee and it works of me.

[Bret4207]

I'm pretty sure if you asked for someone to test a sample for you if you paid the postage both ways, you'd have offers out the wazoo. The larger question is- Why do you want to know? If you're curious and want to know, that's fine. If you think Bhn will solve all your problems with cast, you're in for a disappointment.

[captaint]

What Bret said - plus one. I have a Cabin Tree. It's great. Everybody that has a Lee says they work too.. I really got mine out of curiosity and wanting to keep my alloys consistent. That is easily doable. enjoy Mike

[JonB_in_Glencoe]

I use the Lee set to measure BHN.
send me a sample or 2 or 3 or ??? and I'll measure them for you.
it's best to have recently melted and cast boolits for samples.
no need to return anything.
Jon

[Frank]

Bret4207:

I'm pretty sure if you asked for someone to test a sample for you if you paid the postage both ways, you'd have offers out the wazoo. The larger question is- Why do you want to know? If you're curious and want to know, that's fine. If you think Bhn will solve all your problems with cast, you're in for a disappointment.
Knowing hardness is important, unless you are just using pure lead, then you know what it is already.

[Bret4207]

Knowing the Bhn without knowing the alloy make up tells you what?

[kappy]

I figured it would be wise to figure out the BHN just to make sure that my casts are being made with a consistent alloy... but if folks genuinely believe that it is unimportant, I guess I don't need to bother...

On the other hand, I thank the folks who posted up kits (especially the free ones), and still intend to try them out. I think I can afford a $50 kit.

If nothing else, it is part of the learning process. Once you stop learning, you're dying.

Plus, a friend of mine tells me that he thinks my BHN is around 25. This is purely based upon him biting the bullet... so I'm curious as to how accurate he is.

[303Guy]

I still think two hardnesses should be measured; impact and slow. I do neither just yet but I want to know the values. I think knowing and manipulating the hardness values is a useful tool.

[JohnFM]

When I first got interested in casting my own and started looking around for some info on the subject I asked a similar question and received the same replies.
"Don't bother, no need, waste of time, save your money"

So, I got one. I find the information interesting.
I've been shooting for 60 years and reloading for 50 and have a lot of tools and toys I don't need or seldom use, but I can't think of any I'm really sorry I got.

As I cast some bullets and go through the process of developing loads I'm finding knowing the hardness of what I'm casting is some important information. Right now it may be raising more questions than answers, but I'm glad I can find out what it is.

[1Shirt]

Kinda hard to disagree with Bret on this! However, love my Cabin Tree tester, got it for Christmas 4-5 years ago. Another reloading toy that I just couldn't do withoout. Reloading tools beyond the basics is an addiction. Gotta love addictions, it keeps Lee, Lyman, RCBS and the likes in business.
1Shirt!:bigsmyl2:

[Wolfer]

I bought a lee more for curiosity than a real need. A long time ago I had cast up some WW and took them to a buddy who had a saeco and they tested 16 bhn. I kept some of these boolits separate and when I wanted to know about some new alloy I would put them nose to nose in a vise and which one deformed the most. I also had some pure lead I would test against also. Then I would know if they were closer to 5 or 16. I found that in a 45 colt with correct dimensions anything in that range would work just fine.

If there was any money in it I could be a professional putterer. Just can't seem to make a living at it.

[Larry Gibson]

kappy

I also agree/disagree with bret. I got along fine for many years without knowing the BHN of my alloys. However, I've found that measuring the BHN of my cast bullets adds to my knowledge base and allows me to do things with certain alloys without a lot of the hap hazard guessing and testing that I had to do before. I've used several methods but setteled on the Lee tool as it is inexpensive, fairly simple to use and is as reliable in repeated performance as any of the other testors. I also found a small toy microscope at a 2nd hand store for $12 and easily adapted the Lee scope to it. That makes it very easy, quick and accurate to use.

Larry Gibson

[blackthorn]

I got an LBT tester several years ago and I am very happy with it. It is very straight forward and easy to use.

[Bret4207]

I'm not saying no one should get one. I'm saying simply knowing the Bhn isn't going to cure leading, male pattern baldness or acne. If someone wants one I say get the Cadillac and buy a Cabine Tree, you'll never be sorry. But on an unknown alloy that may be binary, tertiary, or made up of even more elements...Bhn only tells you so much.

[44man]

I have to agree with Bret. I have the LBT and find it the very easiest to use. But it does not cure anything.
I use it like I do a chronograph, just to see after accuracy is found first.
I can tell you my boolits BHN but that says nothing about the alloy itself and 100 alloys the same BHN can all do 100 things different in the gun.
Even taking measurements at different places on a boolit nose will give you different readings, I will be darned if I will poke a hole and use a magnifier and chart.
One time I made an alloy of WW's, tin and antimony that I like. I water dropped and aged the boolits and found them reading SOFTER then plain WW boolits. But I can tell you they are tough and hard and shoot great.

[btroj]

I dont own a tester. My guns don't seem to mind at all.

Like 44man and Bret said, the BHN tells you nothing about the alloy composition. I can have a 50-50 WW/pure bullet water dropped with a similar BHn to a straight Linotype bullet. Similar BHn yet very different results on impact.

[1bluehorse]

My thoughts are if you agree with the BHN, strength, and pressure idea then it would be a benefit to know what the BHN of your bullets is..at least a good ballpark figure..8-10, 10-12, etc;

[Frank]

Bret4207:

Knowing the Bhn without knowing the alloy make up tells you what?
Bullet hardness by itself is an important characteristic regardless of alloy. A bullet must be hard enough to resist obturation and deformation. Obturation, or expansion of the bullet base, increases friction, which breaks down lube and this causes leading. Deformation leads to balance problems and loss of accuracy.

Here is the formula for cast bullet accuracy. For a given pressure/velocity, the bullet must fit, then it must go through a bore in good condition, with lubrication and must be sufficiently hard. Of the last three, any decrease of one can be made up with an increase in the other and vice versa.

Pressure/Velocity=>Bullet Fit
=> Bore Condition
=> Lubrication
=>Bullet Hardness

[mpmarty]

BHN testing is of no value to me at all. My boolets don't lead and are accurate and that's all I care about. I smelt clip-on wheel weights and add a bit of tin and call it good. I've got a LEE hardness tester and have used it and find I can test the same sample over weeks and months and get wildly divergent results so I just don't care anymore.

[geargnasher]

kappy

I also agree/disagree with bret. I got along fine for many years without knowing the BHN of my alloys. However, I've found that measuring the BHN of my cast bullets adds to my knowledge base and allows me to do things with certain alloys without a lot of the hap hazard guessing and testing that I had to do before. I've used several methods but setteled on the Lee tool as it is inexpensive, fairly simple to use and is as reliable in repeated performance as any of the other testors. I also found a small toy microscope at a 2nd hand store for $12 and easily adapted the Lee scope to it. That makes it very easy, quick and accurate to use.

Larry Gibson

Agree 100%. Knowing gross hardess (and the Lee tester is a repeatable way to check it) is just one more little insight into building a load. The more you can measure, and KNOW, the more accurate observations and adjustments can be made. Alloy composition matters a lot, too, but for the most part we guess about that and add this or that depending on how the stuff acts, melt/mush/freeze points, what we think it is, and how the hardness checks, etc.

I got by without a micrometer, hardness tester, or lead thermometer for years, but my shooting results are an order of magnitude better since I got the tools to start quantifying things, and learned how to use them.

One more observation: It's really easy for a guy who's been pouring his favorite, known mix of Linotype/wheel weight alloy (or whatever) for fifty years to say "You don't need a hardness tester, that's just a waste of money" because he knows what he has, and has been doing it so long he can practically tell by smell if the alloy needs adjustment or not, and what adjustment to make if any. Not so easy for a fellow to tell if he hasn't had lots of experience observing the nuances of alloy behavior. If you're new, or even fairly new, my advice is buy a thermometer and hardness tester as a matter of priority before spending money on an electric furnace. With a thermometer and hardness tester, you can take the cheapest, dirtiest, unknown alloys, refine/re-alloy them to your needs, and make great boolits in a cast iron pot over a wood fire with a bent serving spoon. But a $400 bottom-pour furnace won't help you unless you're using foundry-certified metals, or have a lot of experience with what you're doing.

Gear

[Frank]

geargnasher:

Alloy composition matters a lot, too, but for the most part we guess about that and add this or that depending on how the stuff acts, melt/mush/freeze points, what we think it is, and how the hardness checks, etc.

Other than terminal performance, how does alloy composition matter? :coffeecom:

[geargnasher]

Frank, if you don't know how much it matters, you need to do some more shooting!

Push a lead/antimony alloy too fast with not enough tin to form the intermetallic Sb/Sn bond and you'll discover one of the many reasons why composition makes a big difference. Hunting alloys need their own formulation, too, and if you heat-treat or water-quench the composition becomes critical for certain applications. There are many "degrees" of hardness, for example a water-dropped alloy with 1.5% Sb and 1% Sn and trace arsenic and/or sulfur will age to around 16-18 BHN depending on how hot the mould is and how quickly they go from mould to water, and an alloy of 8% Sb and 2% Sn will test the same hardness air-cooled, but hit them both hard with a hammer and the WD'd alloy will smash flat while the other will shatter. The way the alloy takes stress aside from just "hardness" makes or breaks an HV alloy accuracy-wise, "terminal performance" aside. Alloy composition doesn't have to be rocket science, nor does it have to be perfect, but like powder selection, it can certainly make a big difference in the way a load shoots.

Gear

[btroj]

Good advice Gear.
I forgot about the fact that years of experience allow me to get by more by feel than a newbie can. It is scary to think I was shooting cast many, many years ago with not a whole lot of knowledge.

I use a variety of unknown alloys and mix them by eye. I suppose experience let's me get by this way. I have been using one alloy a bunch lately. 18 pounds lead pipe to 2 pounds monotype. Seems to be working well so far. Hardness is unknown.

[Frank]

geargnasher:

Alloy composition doesn't have to be rocket science, nor does it have to be perfect, but like powder selection, it can certainly make a big difference in the way a load shoots.
Alloy can make a difference, but so can many other factors. But in no way does alloy compare to Bullet Hardness, Lubrication or Bore Condition. Those are the 3 biggies that determine what kind of pressure/velocity a bullet can take before it leads and/ or accuracy is lost. I already said alloy was important for terminal performance.

[303Guy]

Obturation, or expansion of the bullet base, increases friction, which breaks down lube and this causes leading.That one should be highlighted! I'm getting base cupping and/or base edge feathering or dragging. That might not be a problem in itself if the dragging was perfectly even but it's not.

From what I can remember I was not getting the same cupping and dragging with a different alloy of similar hardness. That alloy also fragments more readily.

[geargnasher]

geargnasher:

Alloy can make a difference, but so can many other factors. But in no way does alloy compare to Bullet Hardness, Lubrication or Bore Condition. Those are the 3 biggies that determine what kind of pressure/velocity a bullet can take before it leads and/ or accuracy is lost. I already said alloy was important for terminal performance.

OK. Never mind then.

Gear

[Lloyd Smale]

ive owned a seaco and an lbt and know have a cabin tree. Its the class of the field in my opinion and buying one is supporting a member here.

[Bret4207]

OK. Never mind then.

Gear

Pretty much normal. He lives in his own world.

Boolit fit is first, always. Obturation is a part, or rather can be a part of dynamic fit. Aiming to have a boolit obturate is the opposite of what we should be doing. A boolit that fits in the first place doesn't require obturation, it's just harmful. Bore condition is pretty much 'come as you may"- we got what we've got and there's not a lot we can do about it. Lube, alloy, Bhn, seating depths, altered cases, etc., are the tools we use use to help overcome the obstacles to better performance. Even then, there are simply limits to what we can do with cast no matter how hard.

While Franks list includes some of the important features in finding good loads, the implication is plain that Bhn alone will solve issues. It won't. It's a tool. Overcoming stripping or nose slump can be done with a juiced alloy, different powder, heat treating, seating differently, using better designs or by several other ways I'd think. Bhn alone won't tell you much. Bhn won't ever make up for poor fit or a lousy barrel or poorly cast boolits or a great number of other things. Same with saying Bhn can tell us what the alloy is. Nope, not since we got past the days of 2 and 3 part know component alloys. A little copper will make a world of difference and you'll never know based on Bhn.

It would be nice if there was a tool out there that would solve all our problems. There isn't.

[44man]

I was at the scrap yard and a fellow brought in some of the nicest brass and a whole cart of pure lead in 2"x4"X8" blocks. I said is that lead? He said yes, do you want one? He handed me a block.
The guy in the yard had a hand held tool he pointed at the brass and he could tell the exact composition so it could be priced. Worked with radiation.
I don't think it would work on lead but it was amazing.

[Frank]

Bret4207:

A boolit that fits in the first place doesn't require obturation, it's just harmful.
A bullet that fits but is too low in hardness obturates and this causes leading, unless you reduce the pressure and velocity.

Bret4207:

Overcoming stripping or nose slump can be done with a juiced alloy, different powder, heat treating, seating differently, using better designs or by several other ways I'd think. Bhn alone won't tell you much. Bhn won't ever make up for poor fit or a lousy barrel or poorly cast boolits or a great number of other things. S
Actually, it's just the opposite. The reason a bullet slumps is because it is insufficiently hard. BH tells you if it will slump and obturate. What are you trying to do. Get him to lead his barrel and open up his groups? :veryconfu

Bret4207:

Same with saying Bhn can tell us what the alloy is. Nope, not since we got past the days of 2 and 3 part know component alloys. A little copper will make a world of difference and you'll never know based on Bhn.
Nobody's trying to use BH to determine alloy. That's a fignutton of your imagination. We know know alloy we have by weighing the bullet. If in that rare instance we need to worry about alloy, like having a higher Sb level for target work, then we can put them back into the pot and add Sb. [smilie=1:

[mktacop]

kappy

I also agree/disagree with bret. I got along fine for many years without knowing the BHN of my alloys. However, I've found that measuring the BHN of my cast bullets adds to my knowledge base and allows me to do things with certain alloys without a lot of the hap hazard guessing and testing that I had to do before. I've used several methods but setteled on the Lee tool as it is inexpensive, fairly simple to use and is as reliable in repeated performance as any of the other testors. I also found a small toy microscope at a 2nd hand store for $12 and easily adapted the Lee scope to it. That makes it very easy, quick and accurate to use.

Larry Gibson

Now THAT is a pretty slick set-up! I may have to copy what you did there!

[Sonnypie]

I got the Lee,
It is good enough for me,
I don't care you see,
What others say it should be.

The only thing that matters is to have reference for yourself. Especially if you conglomerate with unknown mixtures.
First batch of Wheel Weight metal I melted, cleaned, and ingotted up I looked at the purdy ingots and said to myself:
"Now that's purdy! But nobody on God's green Earth knows what it is beyond 'Wheel Weights', nor if it could be repeated."
So I "bite the bullet" and get RotoMetals Lyman #2 alloy for my rifle, and melt down Magnum Shot for my 45 ACP slugs.
I do BHN for reference. My own reference. Just like I know what powder I use, what primers I use, OACL, bullet weight, lube, and Phase of the Moon.
It also allows some sort of reference when a Friend tries out/tests my cast bullets in his guns with his loads.
Other than that, BHN is just a talking point. Something for folks to yap and argue over.
Common sense is not so common anymore. (Who elected those boobs?) ;)

[44man]

Now guys, use the proper terms. Obturate only means to SEAL, never expansion of a boolit. A proper fit with no expansion means the boolit will obturate in the bore. Expanding a boolit will also make it obturate but you do not obturate the boolit, you expand it to do so.
99% of the time, expanding a boolit to obturate will ruin accuracy and fit is better.
OK, that is off my chest! :kidding:
Some alloys will lead the bore depending on what is in it even if it is the same BHN as another alloy. Seems to be the bonding of metals. Too much antimony and not enough tin. Too much tin. I have n stinking idea! :grin:
I prefer TOUGH instead of hard so a boolit takes the rifling without skid. Hard and tough are related so maybe BHN helps in some cases but I do not want to rely on BHN only.
Bonding of metals on a molecular level is so important to what we shoot. I do not want to break the bond so one metal shears away.

[Sonnypie]

All I need in toughness is for the bullets to go through a hoody and into the flesh and bone within. ;)
How it obturates after that is a non-issue to me. :kidding: :lol:

[Larry Gibson]

Bret4207:

Bullet hardness by itself is an important characteristic regardless of alloy. A bullet must be hard enough to resist obturation and deformation. Obturation, or expansion of the bullet base, increases friction, which breaks down lube and this causes leading. Deformation leads to balance problems and loss of accuracy.

Here is the formula for cast bullet accuracy. For a given pressure/velocity, the bullet must fit, then it must go through a bore in good condition, with lubrication and must be sufficiently hard. Of the last three, any decrease of one can be made up with an increase in the other and vice versa.

Pressure/Velocity=>Bullet Fit
=> Bore Condition
=> Lubrication
=>Bullet Hardness

As this thread progresses I agree with much of what is being said by frank, Bret, Gear, 44man and others. I think they are pretty much singing off the same page on a lot of things even though it appears, in some instances, they might disagree.

Franks list is fairly complete, although somewhat simplistic in that it lumps some things under those items which perhaps might better be served as a standalone component of the "formula". Getting back to the OPs topic; the measuring of BHN certain is a major step in determining #4 of Frank's list. Measuring the BHN gives at least 50% of the "hardness" with malleability and alloy composition being the other important parts.

As I mentioned, along with Gear and perhaps others, that having more knowledge of what your alloys are allows you to do more with cast bullets over a larger spectrum. You don't have to know the exact % composition of the alloy but if you have a good handle on the BHN (by accurate & consistent measurement) and the malleability (by crushing, bending and by visually examining the crystalline structure) then the "composition" of the alloy can be easily adjusted to give a much better alloy for the intended purpose.

Granted if all you shoot is cast in one or two cartridges within a limited velocity load range and you have one alloy that works well then knowing the BHN won't be of much use. However, if your alloy becomes unavailable (linotype and now WWs being good examples and becoming extinct in many areas) then knowing the BHN, malleability of that/those alloy(s) and being able to adjust new components to equal that/those old alloy(s) or create a new one(s) is beneficial and very saving of time, components and a lot of frustration. Also if you want to create a better suited alloy for a different application (low end or high velocity loads for example) then knowing the BHN, the malleability easily allows the addition of other components to change the "hardness" to fit the need of the alloy.

It's all just a matter of the needs and desires of the end user. Some of us have "enquiring minds" and want to know, others are satisfied with what they are using, have no intention of changing and therefore have no need nor desire to know the BHN. Just a matter of what one wants to do is all as there is no "correct answer" as to a "need to know", the BHN anyway.

Larry Gibson

[Larry Gibson]

44man

I believe that the accepted definition of "obturation", as it relates to bullets and cartridges, does include "expansion" as a componant of "sealing". I would refer you to the definition of "obturation" in the Firearms Encyclopedia, by George Nonte and also the use of "obturation" to mean expansion in numerous other writings going back to at least Phil Sharpe in the '30s if not in the descriptions of bullets shot in BP cartridges in the late 19th Century. Even Webster's lists a part of the meaning of obturation as akin to tumere to swell. I think the common thought in ballistics is that "obturation" is the better used term for the slang; "bumping up". All of which means the cartridge case or bullet can "expand" to "seal" either the chamber or the bore/barrel. In the case of the cast bullet when it expands during acceleration the front (nose) most often sets back or "sloughs". Whether it does it straight back or evenly is where imbalance occures. Also when the bullet obturates (expands to seal) during acceleration whether or not the base of the bullet stays perpendicular to the axis of the bore is another question; the answer of which can effect accuracy.

All of which the measuring of the BHN and the determination of the bullets malleability given the composition (along with the other 3 components of frank's formula) will give a better understanding of what the bullet will or is doing during accelleration in a given appllication.

Just my thoughts.

Larry Gibson

[geargnasher]

Larry and 44Man, I think there is plenty of supporting evidence to argue the exact meaning of the term "obturate" either way, but it really is up to us, as an esoteric group who tend to develop our own jargon, to establish the meaning WE want it to have. Dictionary definitions give both the medical definition, the definition in the context of artillery shells, and others which can go either way. Looking at a possible root word would tend to argue the point that obturation is the act of the boolit deforming under pressure to cork the bore, whereas the medical and at least one ballistic definition I've looked up refer to "blockage" or "seal", rather than the act of a boolit deforming.

I maintain 44Man's point of view is the best one, but to each their own I guess. The problem here is that, while it's true that when pressure stress exceeds the elastic limit of the alloy the boolit DOES deform, we don't have an adequate term for that action, so "obturation of the boolit" is substituted. Bret thought there was a ballistic term for boolit deformation under pressure that was separate from the resulting "seal" that that deformation can create, but so far nobody's come up with it.

I'll stick with "boolit 'bumps' or 'slugs-up' to obturate the bore", because that description makes the most sense to me.

As far as alloy composition, the balance of tin and antimony makes worlds of difference to the way a boolit behaves. The nature of the dentrite structure favors different designs depending on the concentration of each, and that affects dynamic boolit strength in a way that isn't reflected in a simple compressive strength test. The intermetallic bond of tin and antimony, together with the effect of which metal is on the primary, secondary, or even third field of crystallization as the alloy cools to a solid (which is totally a function of relative percentages in a ternary Pb/Sb/Sn alloy) makes a big difference in the way a boolit acts when fired through a gun. Add trace amounts of grain refiners such as arsenic and sulfur, and the game changes again. Hardness testing is important to me, but it doesn't tell the whole story by a long shot.

Gear

[44man]

44man

I believe that the accepted definition of "obturation", as it relates to bullets and cartridges, does include "expansion" as a componant of "sealing". I would refer you to the definition of "obturation" in the Firearms Encyclopedia, by George Nonte and also the use of "obturation" to mean expansion in numerous other writings going back to at least Phil Sharpe in the '30s if not in the descriptions of bullets shot in BP cartridges in the late 19th Century. Even Webster's lists a part of the meaning of obturation as akin to tumere to swell. I think the common thought in ballistics is that "obturation" is the better used term for the slang; "bumping up". All of which means the cartridge case or bullet can "expand" to "seal" either the chamber or the bore/barrel. In the case of the cast bullet when it expands during acceleration the front (nose) most often sets back or "sloughs". Whether it does it straight back or evenly is where imbalance occures. Also when the bullet obturates (expands to seal) during acceleration whether or not the base of the bullet stays perpendicular to the axis of the bore is another question; the answer of which can effect accuracy.

All of which the measuring of the BHN and the determination of the bullets malleability given the composition (along with the other 3 components of frank's formula) will give a better understanding of what the bullet will or is doing during accelleration in a given appllication.

Just my thoughts.

Larry Gibson
No argument Larry. Expansion can be needed to obturate, like the Minie' ball. Yet fit works better for shooting and even a good fit to the bore with a Minie' ball increases accuracy. The less damage done to the boolit, the better.
I do not and will never believe in "bump up." Slump is also very bad. A recovered boolit should look exactly like it was cast other then rifling marks.
Definitions can varie but obturate means to seal no matter how obtained. It is how you attain it that makes boolits accurate or not.

[Bret4207]

Bret4207:

A bullet that fits but is too low in hardness obturates and this causes leading, unless you reduce the pressure and velocity.

Really Frank? Explain how a wadcutter or Loverin will obturate please. A boolit can be made to obturate in many instances. It can also be controlled by using lower pressure loads, powders, etc. You don't necessarily NEED to go faster than you need to go, now do you?

Bret4207:

Actually, it's just the opposite. The reason a bullet slumps is because it is insufficiently hard. BH tells you if it will slump and obturate. What are you trying to do. Get him to lead his barrel and open up his groups? :veryconfu

Right Frank, the answer is simply going to a harder alloy. Sure. The reason the boolit slumps is because of pressure and the pressure curve. You have choices in how you address that.

Bret4207:

Nobody's trying to use BH to determine alloy. That's a fignutton of your imagination. We know know alloy we have by weighing the bullet. If in that rare instance we need to worry about alloy, like having a higher Sb level for target work, then we can put them back into the pot and add Sb. [smilie=1:


You just contradicted yourself Frank. YOU said we can determine alloy by weight in another post.



More laterFrank, gotta go.

[44man]

I like Gear's definition of metals best of all.

[Frank]

Bret4207:

You just contradicted yourself Frank. YOU said we can determine alloy by weight in another post.
You're mistaken. I said we know the alloy we have by weighing the bullet. I never said BH had anything to do with weight. :veryconfu

[2Tite]

Kappy, The Lee is easy to use, fairly inexpensive and accurate if used properly. Get one and play, experiment and have a good time. Keep notes, establish yourself a chart with baselines of pure lead- tin mixes. Plot your alloys' hardness on the charts and have a good time. You may learn somethings other folks don't know. Do what you want to and have a good time....

[geargnasher]

Bret4207:

You're mistaken. I said we know the alloy we have by weighing the bullet. I never said BH had anything to do with weight. :veryconfu

Frank, not trying to beat you up here, but unless you have a pure metal or no more than two pure metals mixed, you cannot determine the composition by weight alone. Even multi-variable calculus cannot solve for three variables and three unknowns.

Even if exact hardness and specific gravity are known, it is impossible to determine accurate composition with three or more metals in an alloy, because there are an infinite number of percentages that will yield identical mass/volume and hardnesses.

Gear

[Frank]

geargnasher:

Frank, not trying to beat you up here, but unless you have a pure metal or no more than two pure metals mixed, you cannot determine the composition by weight alone. Even multi-variable calculus cannot solve for three variables and three unknowns.

Even if exact hardness and specific gravity are known, it is impossible to determine accurate composition with three or more metals in an alloy, because there are an infinite number of percentages that will yield identical mass/volume and hardnesses.

Gear
It's enough to tell me if I need to put it back in the pot. For example, for a bolt gun I like them a little extra strong.

[Larry Gibson]

44man was stating "the exact meaning" which in the useage of the term "obturate/obturation" does not mean just "to seal" We nay have obturation of a bullet where the bore is not "sealed" yet the bullet expanded or obturated. In the case of the cartridge case there must be obturation/expansion for the case to seal the chamber or, again there may not be. Exapansion is the integral part of obtruation but "sealing" is not as both the case and the bullet may obturate yet fail to seal.

Concur that hardness does not tell the whole story as I've said that in many other threads. Mallability is as important and is an integral part of "hardness". That's why Franks' formula is over simplified as i explained and both of you (Gear and 44man) and reiterated. We are singing off the same page here as I believe Frank is singing along with us.

Some want to know the BHN because it assists in their alloying cast bullets to suit various needs. Others don't care nor need to know as their alloy used suits their needs.

Larry Gibson

[303Guy]

I'll stick with "boolit 'bumps' or 'slugs-up' to obturate the bore", because that description makes the most sense to me.I'm with Gear.

Makes me think of the word 'pistol'. I used to call any handgun a pistol. Then I realized a pistol was a semi-auto and a revolver just that. Actually a pistol is a pocket dagger! Or was. Before that is was a pocket weapon. The meaning of words evolve. But to me obturate still means to block or to seal. We may be fighting a losing battle though.:???:

[Bret4207]

geargnasher:

It's enough to tell me if I need to put it back in the pot. For example, for a bolt gun I like them a little extra strong.

Well that's a great and very accurate definition o what, why and where you need to head. I hope that was your attempt at humor. Regardless, you can't determine alloy by weight or Bhn. There was a chart some years back that gave figures for tertiary alloys based on comparison with lab grade components. I have also seen a chart that gave, in the authors opinion, alloy make up based on Bhn. Both charts, while well meaning I'm sure, were inaccurate, especially with unknown alloys that might contain more than 3 elements.

Hardness, softness, toughness, brittleness, malleability. All ambiguous terms. We can get the best home scale Bhn tester and al it does is give us a comparative reading. It tells us nothing about the alloy and how it will react except in comparison to other alloys using the same tester. It's a tool. We know that if we quench we'll have a harder boolit. How much harder varies, how it will react varies. Simply making things harder doesn't necessarily mean our troubles will end. We have people shooting almost straight WW alloy, of more or less unknown makeup, well over 2K fps and even "softer" alloys at the same speeds. We have people that need linotype to exceed 1600 fps too. Kinda makes me wonder why when all we need is to go "harder".

Harder can work fine, no doubt. But it's not a sure fire cure for anything. That's all I'm trying to get across.

[btroj]

I am squarely with Bret on this one. Harder isn't always the answer. The older I get the softer I shoot my Boolits. Then again, I don't have a tester so is upload I can't say that, no BHN to put in it!
The hardness is ONE measure of a bullet. Only one.
I wonder how many machinists or engineers would agree that all steels with the same "hardness" are the same? Why is a lead alloy any different?
As for telling anything about alloy composition from bullet weight? What? So you know it isn't pure lead! Wooo hooo. We already knew that. It MAY let you know if your alloy is consistant from batch to batch but even that isn't exact.

I mix all my alloys by eye. I use a vague system of hard to soft. I use feel and my thumbnail for a tester. I listen for the "clink" of the bullets in a pile. Somehow they keep working for me. We can make this as simple or as hard as we want. I prefer shooting over testing a bunch of bullets to measure something I don't really care about anyway.

Harder is better? Not to me.

[44man]

I just go by what the gun wants. Usually WD WW metal alone and some revolvers give me better accuracy with a little antimony and tin added.
I never go too hard but have found my .44 will only shoot a Keith with accuracy when I reach 28 BHN. With a better nose guidance I can shoot 50-50 WW and pure, oven hardened. I do get a few fliers but not bad enough to harm hunting loads. Even though oven hardened they expand in deer. Hardening prevents slump and allows grip to rifling without ruining expansion. Works fine in the 45-70 revolver.
When I try air cooled WW metal, groups open and gets worse as I go softer. Nothing at all to do with leading, just accuracy. Lots of stuff can be shot without leading the bore. Pure with tin can be shot too, but not from me! [smilie=s: Anything that goes over 1" at 50 yards is rejected.
I use WD, WW boolits in my .475 and .500 JRH too. Before I got the Ultra Dot for my .500 I put an old scope on it. I laid 5 shotgun shells on their sides and shot 5 straight at 50 yards in the bases. I only found 3 in the weeds. They are about 3/4". Both guns kill like the hammer of Thor so there is no need to use soft boolits. I do not see myself changing alloys for any reason, it is more work to make softer anyway. Plain old WW's work just fine.
This is what counts to me, never what BHN a boolit is.

[44man]

Strange a 1/2" boolit can hit 3/4" targets at 50 yards but if I can see them, I can also hit shotgun shells at 100 yards, just stood up on the rail.
Cast will actually out shoot jacketed. Too much is made of BHN.
My WW's are from all over and are never the same batch to batch. It means nothing at all. If one boolit is 22 BHN and the next batch is 18 BHN, I dare anyone to tell the difference at the target.
Do not get uptight about hardness, just find what your gun shoots best and if they are softer, great. I can not shoot too soft and over 58 years of fooling with everything, nothing will make me change.
Just about every accuracy problem is from boolits that are too soft and expansion to obturate might be the worst.

[Frank]

The purpose of alloying is to increase bullet hardness. That is also the purpose of heat treating. You can go backwards if you need expansion. Brinnell Hardness testers measure the results. Heat treating is the preferred method. Alloying to get hardness can result in too brittle of bullets, but they will be just as good as a heat treated for targets. Making a bullet harder lowers pressure. A harder bullet resists base obturation. A gas checks acts like a hard base and doesn't obturate. This reduces friction, lube breakdown and leading. But there must already be a few other factors, like fit, lube and bore condition must be good.

[Bret4207]

The purpose of alloying is more than just going harder. As for your claim that heat treated will be the same as alloyed...if you're still believing that then it explains some things about your understanding of the way things work. Same for the idea that harder means lower pressure. Nope, not by a long shot.

Sorry Frank, but you're either not explaining your theory very well or you have some basic misunderstanding about alloys, their response to pressure and how alloys differ. No insult intended, but you keep coming back to a point that simply isn't correct. This stuff is far more complex in it's variations than you imply and state. Took me quite a long time to get it straight in my head too.