Oregon Trail Laser-cast BHN hardness

[Jech]

Spent some time discussing the ever controversial subject of bullet/alloy hardness in the context of controlling leading in auto-loading handguns. He recently purchased a number of Lasercast 200gr LSWC bullets from Oregon Trail Bullet Company. This is a successful company local to my home state so I want to preface by clearly stating I intend no negative commentary towards them AT ALL. Also, for the sake of an apples-to-apples discussion, we were strictly about aspects of hardness, not proper fit.

In an excerpt from a document posted on their website (http://www.laser-cast.com/files/Understanding_bullet_obturation.pdf)...

For lead alloys, yield strength has been defined by scientific research as 480 times the Brinell Hardness Number (BHN). Fore example, a bullet with a BHN of 22 will have a yield strength of about 10,600 psi. Hence, the bullet’s base will be the first portion to obdurate at a chamber pressure of 10,600 psi.
This is completely different from anything I've ever learned. If someone told me 22BHN was perfect for my XD45, I'd tell them to take a hike. I'm used to dividing a cartridge's SAAMI pressure maximum by 1,422 to calculate the appropriate BHN for obturation. Example 45auto's standard maximum of 18,000psi divided by 1422 = 12.66BHN.

Has anyone else ever heard this 480 figure before? 22BHN obturating at 10.6k PSI is borderline absurd to me but I'm always learning. Hoping to hear from the experts!

[35remington]

No, they botched the mathematics.

Been discussed here before. They need to correct the information. It's not right.

[lwknight]

I concur with 35Remington.

[Jech]

No, they botched the mathematics.

Been discussed here before. They need to correct the information. It's not right.

Ah, my apologies, I should have used the forum search before I put all the time into my post.

So the bottom line is Lasercast may be appropriate for full power loads in calibers such as 40s&w and 9mm but will just plain be too hard for 45auto.

Thanks guys! Now I gotta help my buddy find a use for 22BHN 45cal bullets :holysheep

[runfiverun]

they make great hardening agents.
i bought a bunch of lazercast for my 41 mag so i could lead up the bbl, and see which of my alloy/lube combo's would clean it up.

[leadman]

They may work in a 45ACP if the fit is good. The biggest issue with using commercial cast besides the fact they are excessively hard IMHO is the large bevel bases on most of them.

I have melted down commercial cast and poured them into my molds and the alloy worked good. The boolits I cast were flat based and fit my guns.

[Jech]

Silver melts at 1763F which is way too high for the average bullet caster's equipment, however, antimony's melting point is 1167F. Once Oregon Trail has alloyed it in, does the whole 7 metal blend melt down okay in a casting pot?

[mpmarty]

It seems some of us think in order to perform a boolit has to deform (obturate). If a boolit is the right size to begin with hardness doesn't make any difference at all IMHO.

[HARRYMPOPE]

It seems some of us think in order to perform a boolit has to deform (obturate). If a boolit is the right size to begin with hardness doesn't make any difference at all IMHO.

I agree and have argued this before.When i was younger i only had Linotype as dad was a printer.I had HG make their #503 for my Ruger SBH throats.It never leaded though my expert buddies said it would.Some goes for my plainbase 30 caliber stuff.Everybody told me softer is better so it bumps up.Well ..casting the bullets from Linotype or other harder alloys was better as the bullet was larger and fit properly as cast.Up until abut 5 years ago i never used anything but Linotype with equal results to the "wheelweight guys" i shot with.Now i shoot various range scrap and such and its working too,but i still shoot lino when i want to ring a rifles accuracy out.I believe if Linotype was cheaper and more available more people would shoot hard bullets and report good results.

HMP

[Bret4207]

I'm glad to see people getting beyond the "make the boolit obturate" idea. I got stuck on that hump too for a while. Why people thing we should work to produce perfect boolits, size them to the "perfect" diameter, load then with love and care and then mash the living heck out of them to the point they become putty is just beyond me. Obturation can be a tool, but like depending on Bhn as an answer to your leading problems, it simply fails.

[44man]

Silver melts at 1763F which is way too high for the average bullet caster's equipment, however, antimony's melting point is 1167F. Once Oregon Trail has alloyed it in, does the whole 7 metal blend melt down okay in a casting pot?
I alloy pure antimony into my mix at 600*. You do not want it too hot and I use a thermometer. The flux is the key along with contact to the other metals with no oxygen.