Hardness for 41 magnum bullets (boolits)

[pineknot]

I'm just getting started casting so I have a lot of newbie questions to ask. I just found out that different loads need different hardness of the bullets to properly function at a given pressure. If I understand this correctly harder isn't necessarily better. First question, So what hardness do I need for a 41 magnum where the pressure is about 35,500 psi. ? Second question, will a gas check have a bearing on how hard the bullet needs to be to function properly. Third question, does powder coating vs. traditional lubes make a difference as far as bullet hardness? I would appreciate any information.

[tigweldit]

pineknot, Welcome to a great forum. All the questions you have asked are good and valid. You are correct that harder isn't always better. You should first determine what your loads are going to be used for. Target, plinking, hunting,and self defense all call for different load characteristics that you will be putting into them. The boolit hardness or softness can help you tune each load for your desirered results, without leading. I have been reloading and casting .41 Mags since 1969, so I have some experience with this caliber. I do powder coat with a Harbor Freight gun and I like the results a lot. I also use carnuba blue when just going with my Lyman sizer for easy bulk target boolets. For my hotter loads, I use Lyman #410610,powered coated, with an annealed gas check. My alloy is 75% COWW, 23% pure, and 2% tin. Very accurate, as just about every .41 Mag boolet is. For my plinking loads, I like the Lyman #41032, or the Lyman #41026 with 50% COWW, 48% pure and 2% tin. Blue lube, 8 gr.Unique, accurate, no leading fun load to shoot all day. Hope this helps you out some, and once again welcome to a great forum. The .41 Mag is my favorite cartridge.

[pineknot]

Thank you Sir, Yes it does help. I was looking at using COWW and 2% 95/5 solder which would probably been too hard. Now I need to find some pure lead. You mentioned annealed gas check, that's the first time I've heard this. Why is this a necessary step? And how do you do this? Do you do this with both copper checks and aluminum checks? Like I said I'm just starting and know next to nothing, but want to learn.

[JonB_in_Glencoe]

pineknot,
Welcome to the forum.
You've asked some good questions.
tigweldit gave you some good answers.

If you haven't read the Lyman cast bullet handbook 4th Ed. ...find one and read it. It goes into detail about the all the facets of casting boolits and loading castboolit ammo. It is a great resource.

Also, the LASC link at the bottom of our webpage is a great resource about boolit alloy.
http://www.lasc.us/CastBulletNotes.htm
if you scroll halfway down that page, look for the chart "Approximate "Maximum" Chamber Pressure For Lead Alloys (PSI)"
That is a great guide to what alloys to use for what pressure loads.

[JonB_in_Glencoe]

Annealed GC:
Sometimes a GC seats stubbornly, making them difficult to crimp on squarely during sizing. Annealing them (copper or Aluminum) will soften the metal allowing them to be seated easily and squarely. I've never needed to do that, but others stated they use a Hotplate with a skillet or just a piece of metal on the burner, some use a propane torch.

[Larry Gibson]

pineknot

"First question, So what hardness do I need for a 41 magnum where the pressure is about 35,500 psi. ? "

A BHN of 12 - 15 will do nicely with well designed PB'd cast bullet such as the RCBS 41-210-SWC. COWWs + 2% tin will get you there. Let the bullets air cool and "age" for 7 - 10 days before sizing, loading, etc.

"Second question, will a gas check have a bearing on how hard the bullet needs to be to function properly."

Yes, with a GC'd cast bullet you can use much softer more malleable alloys. I prefer a 20- 1 or 16-1 (lead-tin) alloy for my full house 357, 41 and 44 Magnum loads.

"Third question, does powder coating vs. traditional lubes make a difference as far as bullet hardness?"

Can't answer this one as I've found no need to PC any handgun bullets.

[Motor]

I have some old commercial 210s that are 18BHN. They actually need to be driven hard to work. If you try to load them light the lead foul. I believe it's because they are too hard to obstruate at low pressure.

I recently bought the Lee 210gr mold. I'm casting my alloy around 12BHN but I'm also using powder coating. I can shoot these mild to hot without any gas checks without any problems.

Motor

[pineknot]

Thank You gentlemen, I appreciate the information. Always a good idea to ask someone who has experience for their wisdom before you go blundering around trying to figure it out on your own.

[lightman]

I use clip-on wheel weights in all of my magnum pistols. The BHN runs 12-14. I never have never used anything softer so I don't know how that would work. I have used harder alloy and it was not as accurate.

[mfraser264]

Have shot 3,000 to 4,000 rounds of high velocity loaded cast lead alloy bullets in the .41 magnum through 2 different handguns. Linotype and a gas check in the Lyman` Seaco molds have worked very well. No leading but a suggestion would be to check for a smooth polished barrel. Typically I'll run 500 jacketed bullets through my revolvers before transitioning to cast lead alloy bullets. The classic Lyman #410610 has worked very well for me even sized at .410". Enjoy the .41 magnum and welcome to casting your own.