Bullet expansion testing

[melloairman]

Has any one done or no were I might be able to get info on expansion . Such as different bhn , but same bullet . May be 8, 12, 15, and 22 bhn . Marvin

[btroj]

BHN alone is not a valid factor. Too many ways to get to a single BHN yet the alloy has very different properties.
An example would be air cooled vs heat treated. Very different BHN from a single alloy yet they will behave very different than other alloys with the same BHN. Say linotype at 18 BHN vs a heat treated wheel weight. They may have the same BHN but the wheel weights will hold together in most hunting situations but the Linotype could fracture.

BHN is ONE aspect of an alloy. What about malleability or ductility? These are very important for penetration and expansion yet have little to do with BHN.

My suggestion is to test the bullets you want to use cast from the alloy you plan to use. This is the only way to know for sure.

Brad

[fredj338]

I agree w/ btroj, it's more about alloy than hardness, but they do kinda corss over. A bullt w/ antimony in it will want to fracture instead of expand. Lead/tin alloys are more ductile. The HP design plays into it as well. Cup points, shallow w/ thick HP sides, will expand more & not fragment as much. Deep HP w/ thin sides will almsot always frag & sping off at higher impact vel. I use wetpack to test mine.
http://img.photobucket.com/albums/v703/fredj338/44-272.jpg http://img.photobucket.com/albums/v703/fredj338/452-268-1K.jpg
http://img.photobucket.com/albums/v703/fredj338/45-215gr.jpg http://img.photobucket.com/albums/v703/fredj338/9mm-136-1200.jpg

[303Guy]

Hard question to answer. Here's some of what I've found.

http://i388.photobucket.com/albums/oo327/303Guy/MVC-451F.jpg 99% weight retension!
http://i388.photobucket.com/albums/oo327/303Guy/MVC-458F.jpg
http://i388.photobucket.com/albums/oo327/303Guy/MVC-481F.jpgHard alloy versus ductile alloy.
http://i388.photobucket.com/albums/oo327/303Guy/20gr2205_146PP.jpg This one was a bit faster than the others!

These were fired into sand at the muzzle. I'm in favour of ductility and toughness over hardness.

I use scrap lead pipe with some plumbers soldered joints (for the tin) added and a little copper dissolved into the melt. Just a tiny bit! One has to 'tin' the copper before immersing it in the melt. No more than 0.06%).

These are rifle boolits at reasonable velocity.

[1Shirt]

I agree with all of the responses. I also am fond of Paco Kelly's mag shot casting method. You might want to google that article.
1Shirt!:coffee: