What is certified lead?  Pure lead or something with tin added?

Chemistry, chemistry for some time now folks have been led to believe that hardness was the goal to shoot for. And if you made up a brew of certain material and the hardness came out to a certain Brinell figure you had a certain lead Alloy. NOT SO!
You have a certain hardness. Just because it matches some Lead/Tin alloy it is not the same Alloy. I do know and understand that many shooters get excellent results from mixed alloys that they create with experimentation. But if you make up a good alloy brew and achieve it with addition after addition when you get done and have a big batch what do you do when it ruins out. Not always easy to reproduce unless you have kept meticulous records. 25/1 alloy is 25Lbs of pure lead to 1Lb of pure tin. Not sure of hardness, don't care as it shoots really well in all my Rifles. Now I will admit I am not a serious Bench Rest shooter so my efforts and results may be suspect in many others eyes. But I do know my Rifles shoot far better than I can usually hold but when I get what I call the Hail Mary shots where everything settles down solid and the shot goes off good and my follow through is good, the bullet hole shows up just where I last saw the Crosshairs on the Target. Then I am satisfied I have  good Alloy, Load, and rifle. Hth Regards, FITZ 

That's why I took ALL my scrap lead, ww and lino and consolidated into lead+tin (30:1), ww+tin (20:1) and linotype.  3 batches.  Took samples into work and had them analyzed.  Don't have a clue to hardness, but when I plink I use the WW+, when I shoot Scheutzen I mix some tin to make 20:1 and when I get around to .22's I'll use lino.

Key word here is that I KNOW what I'm shooting by x-ray diffraction analysis.