I haven't seen any measurable difference between the two brands but it has been a while since I have shot either one since I mold my own balls. If I were going to try to find any difference between the two, I'd weigh a bunch of each and see how close each comes to the expected weight and how much variance there is within each brand. I'd then make a bunch of measurements of the diameters of the balls and do the same math to find how much variance in size each has. Finally, I'd compare their relative hardness using the following method:
Here is a way that is accurate and free.
You have to work on your math a bit though.
I use two 50 cal REALS instead of bottle caps and align everything in a Styrofoam sleeve in the vice.
I found I could get accuracy to 1 BHN by doing 5 samplings and then averaging my results.
The instructions are from the Corbin website.
Here is a simple way to test the Bhn number of unknown lead samples: all you need is a caliper, two bottle caps, a vise, a 5mm diameter (aprox. size) ball bearing, and a known pure sample of lead (Corbin can furnish pure lead of 99.995% Pb with trace silver).
Melt enough lead to fill one bottle cap with unknown sample, and the other with known pure lead. Make sure the surface is smooth and flat when the lead hardens and cools.
When the lead is cold, put the ball bearing between the two lead surfaces and squeeze this "sandwich" in the vise until the ball is driven partly into both surfaces (just enough to make a fair sized dent, but not past the middle of the ball).
Remove the sandwich and measure the two dent diameters. First measure the known pure lead dent and write down this number. Then measure the dent diameter in the unknown lead sample and write it down. Square both numbers (multiply times themselves). Then divide the resulting square of the unknown lead dent diameter into the square of the known pure lead dent diameter. This could be written as (L times L) divided by (X times X) where L is the pure Lead dent diameter, and X is the unknown lead dent diameter.
The answer should be a number of 1 or greater. If it is a fraction, or less than 1 in value, you have inverted the two dents and divided the wrong way. In that case, try again. When you get an answer that is 1 or greater, multiply it by 5. This is the actual Brinnell Hardness Number of the unknown sample.
Here is the formula:
H = 5 * (D1^2)/(D2^2)
...where H is the hardness of the unknown sample in Bhn number, D1 is the diameter of the indentation formed in the known pure lead sample, and D2 is the diameter of the indentation in the unknown hardness sample.
By then, you will be able to give a definitive answer on how the two compare. Otherwise just take the simple route and shoot the damned things and see how each one shoots.
I long for the day I can blame my shooting results on which round ball I used.
