The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Thread Tools Search this Thread
Old September 22, 1999, 12:10 PM   #1
Jack Straw
Senior Member
Join Date: July 26, 1999
Location: Georgia
Posts: 362
Somewhere along the way I came across a way to determine alloy hardness relative to pure lead. It required placing a steel bearing between a piece of pure lead and a piece of alloy and then squeezing them together in a vice. By measuring the indention on both samples and applying a mathematical formula to those measurements one could determine the alloy's hardness. Does anyone know that formula or any other "homemade" means of measuring alloy hardness?

Jack Straw is offline  
Old September 23, 1999, 05:54 PM   #2
Senior Member
Join Date: December 10, 1998
Location: NY
Posts: 680
Jack, The only thing I'm aware of is in the Lyman handbook where they used a special fixture to hold a sample of lead in one of their reloading dies. An indenter was then pressed against a sample of lead with a certain amount of force that was measured. That is the key thing,you have to exert the same amount of measurable force on each sample in order to have an accurate measurement. My saeco tester does that. However, it's scale is not in Brinell and is only graduated in arbitrary numbers(1-10).

When I come across an alloy where I want to get an idea of it's hardness, I'll either drop it on a hard cement floor or hit it with a hammer while holding it. The duller the thud it makes the softer it is. Some harder alloys like linotype will actually "ring" when you hit them.

I'll check into my references for you. Sorry not to be of more help.

Without the 2nd Amendment,the Declaration of Independence is an old post card and the entire Constitution is just notes from a bridge club meeting.

Contender is offline  
Old September 23, 1999, 07:05 PM   #3
Senior Member
Join Date: February 28, 1999
Location: Arizona, USA
Posts: 725
I believe the article you are referring to is "Measuring the Hardness of Cast Bullets" in the booklet, "Cast Bullets" by Col. E.H. Harrison published by the NRA. It is on page 29. Quantrill
Quantrill is offline  
Old September 23, 1999, 08:08 PM   #4
El Chimango Pete
Senior Member
Join Date: January 11, 1999
Location: Sierras de Cordoba - Argentina
Posts: 352
Most hardness testing, from steel to lead alloy, is done by indenting a sample under a standard load and then measuring the size of the dent. By indenting between a substance of known hardness (pure lead, Brinell Hardness Number - BHN = 5), the ratio of one t'other simplifies matters quite a lot. For soft materials a ball is usually used - in this case a steel bearing ball at 7/16" will do. Lyman uses a standard load of 100 lbs, presses ball between lead and sample for 3 secs. Measure dent in lead (diameter, any unit will do), then same in sample. Divede first by second. Square the result. Multiply by 5. You should have the BHN of the sample.
Some figures:

Pure lead , BHN = 5
Wheelweights, no heat treat, BHN = 9
Wheelweights, heat treated, BHN = 27
Linotype, BHN 21

(from Lymans Cast Bullet Handbook - but the physics checks out OK though the method is a little 'rule of thumb')

Banging a head against a brick wall, by the way, should not be considered a valid test for IQ. - regardless of the diameter of the dent
El Chimango Pete is offline  
Old September 24, 1999, 09:18 AM   #5
Jack Straw
Senior Member
Join Date: July 26, 1999
Location: Georgia
Posts: 362
That's the one I'm looking for! Thanks much.

My sweetie often questions my IQ and offers to verify her suspicions with the brick wall test; I'll see that she reads your message. The brick wall thanks you.


Jack Straw is offline  
Old September 29, 1999, 12:52 PM   #6
Senior Member
Join Date: November 19, 1998
Posts: 986

Is there any conversion chart for the Saeco tester to Brinnel hardness?

I have one of those things from a garage sale, but have no instructions for its use. It appears to use a vernier scale on the readout, right?

Cheapo is offline  

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT -5. The time now is 12:36 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2017 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent:
Contact Us
Page generated in 0.05089 seconds with 9 queries