Rockford Rams Hardness Tester Model 30-R

[tenneesse]

I have a 30-R with no manual. Working on that currently without much success but anyway, I have a number of questions.

Can anyone tell me if the HRB scale is reflecting Brinell hardness?

Im looking for a conversion chart that shows the equivalency of Rb to Brinell if they are different I'm assuming they are.

This is a nice unit provided Im getting accurate reading. I used a bullet measured on a Lee testor to calibrate mine and the bullets Im testing seem to be reflecting what I would expect them to measure, or hope they would.

Does anyone have any experience with this unit? They went out of business sometime ago and the buyer doesn't make them anymore or have anything relative like standards.

How does measuring Brinell differ and is Brinell hardness BHN different than HRb?

[KYCaster]

Rockford?.....or Rockwell?

Search Wikipedia for Rockwell hardness and Brinell hardness, you'll probably find enough info to confuse you.

Rb (Rockwell B scale) and Brinell overlap to some extent, but most of our useful lead alloys are far below the Rockwell B scale.

HTH
Jerry

[tenneesse]

Rockford?.....or Rockwell?

Search Wikipedia for Rockwell hardness and Brinell hardness, you'll probably find enough info to confuse you.

Rb (Rockwell B scale) and Brinell overlap to some extent, but most of our useful lead alloys are far below the Rockwell B scale.

HTH
Jerry

Rockford Rams Products made the Model 30 Rockwell hardness testor. They were located in Rockford Illinois. Ain't that a mouth full!

I found a ton of conversion charts using google searches and what you said seems to correlate to what I have been seeing is the softness of lead is way below the cutoff for the B scale.

I'll give Penn Bullets a call and see if Mr Palermo can shed some light on it.

If I knew the force being applied with my model 30 I could do the math and get an accurate measurement but with out the spec sheet Im not sure how to measure the pressure applied to the indentor.

It doesn't use hanging weights like many Rockwell testers use it has an adjustable spring and the force is applied depending what Rockwell scale A,C,B,or E one chooses and calibration blocks for each scale but no standard for very soft materials like lead alloy.