Brinell Hardness - Newbie

[broylz]

how does the brinell hardness rating factor into reloading?

i have an option of a rating of 12 or 18. i am using 18 this go around. my load will be worked up with a 200gr LSWC for my .45 1911 with Unique. with the harder bullets need a faster powder? hotter powder? more velocity? etc...

can someone please explain how it factors in?

[stubshaft]

You could probably get by with 12BHN and not be able to drive them fast enough to lead. Of course this is assuming you are using a quality lube and the boolit is SIZED properly for the barrel you are shooting them from. There are so many factors involved that BHN is only one of the components.

[Bret4207]

If you're sticking to standard speeds in a 45ACP you can use anything from about 8 on up if your boolit fits the gun. Do not worry over Bhn in handguns till you know what you're looking for and see evidence you need a harder alloy. Simple WW alloy at 8-9 Bhn can be heat treated upwards of 15 Bhn. The "hardcast" alloy is ad hype.

[qajaq59]

While we are on the subject... Is there an industry standard for the BHN of wheel weights?

[Bob Krack]

Hah!

There is not even an industry standard on the composition of wheel weights!

They're getting there though, all zinc or all steel or plastic.

[helg]

Check the article

http://www.lasc.us/FryxellCBAlloyObturation.htm

In addition to answer on your question (alloy composition is not the only factor for bullet BHN), it has explanations and a simple formula for acceptable chamber pressures for a given BHN.

[runfiverun]

chamber/peak pressures are not the total determining factors for an alloy either.
where they occur for how long the composition of the final bhn and how the alloy is manipulated are factors too.
just use the softer alloy and unique powder you will be happy,or the harder and bullseye.

[Bret4207]

R5R brings up a good point. You can have 3 different alloys all measuring 13 Bhn ( for instance) and all will have different qualities.

[cajun shooter]

For 45 ACP loads, nothing harder than 12 is needed. Read the sticky section by Glenn Fryxell. When Elmer was working up loads for the 44 mag he was shooting at most times lead in the 9 range. I have never loaded any 45 that could not work well with bullets in the 12 range.

[sqlbullet]

I would say you really want the 12. If they are a little undersize, the 12 will bump up much easier than the 18. Matter of fact, I don't know you can get enough pressure in standard 45 ACP loads to cause an 18 to obturate.

And, keep in mind, a bhn of 12 is definitely hard-cast. The term was coined back in the days of soft lead factory rounds to describe stuff guys like Elmer Keith were casting using a little tin in lead.