Home Forums Reloading Handgun Reloading Brinell hardness & muzzle velocity question

I am going to purchase some hard cast lead bullets, 158gr SWC, and load up some target/plinking rounds for my GP100 357 mag.
Being new to this, I have been doing a lot of reading, and I now know that you have to match the "best" or "most-appropriate" Brinell harness to the muzzle velocity you plan on shooting to avoid/minimize "leading".

I know I will need to do my testing to come up with some good "fits" that do not lead-up too badly, but am looking for some recommendations from experienced folks.

So, what Brinell factor do you recommend I purchase for the following muzzle velocity ranges:
800 to 1,000 fps
1,000 to 1,200 fps

Also, who is your favorite hard cast lead bullet supplier? Looks like they all have approx the same price, but no doubt some are higher-quality and better customer service?

Thanks for your suggestions on this!

Crab

Bnh 12 for up to 1000, Bnh 18-20 for magnum velocity. Some say Bnh15 is good enough but for 357 mag 158 @1250 I use Bnh18 from Missouri Bullet Company. Lasercast and Magnus are also good.

Addendum not necessary but I just use the same bullet for all velocities as I had some swaged cast from Hornady that leaded my GP100 something fierce even at 38 special speeds.

Thanks much for your info, Swifty!!

:-)

Crab

"hardcast'' IMO is a useless term, undefined. Or I have never seen it defined. So, to get the best results...accuracy and zero leading your bullet needs to obturate slightly to seal properly (gas cutting/leakage causes leading). First off you need to know the Bhn of your bullets. Get a Bhn tester, or read up on the use of drawing pencils to determine hardness. Cast Boolits forums is your friend here. Example...let's say you bought bullets of Bhn 15 (Lyman #2 alloy)...what pressure load do you need for Bhn 15 to go plastic and seal the bore? Constant 1440 x 15= 21,600 psi (not cup).
If you research your loading books that list pressure, like Lyman, you can find a load that will make your bullet work.
Unfortunately, to further confuse the issue, my experience is almost the opposite of Swifty's. When I have leading issues (very very seldom) I either increase the charge or go with a softer bullet. But, I am not operating at his speeds and pressures, and if you are on the upper end of power in your cartridge, I'd listen to him. I stay pretty much in the low to mid power levels...all my custom molds are built to drop the right dimension bullet of wheelweights and 5% tin...giving around a 12 Bhn. Mostly because my revolvers and rifles are well over a hundred years old and designed originally for black powder.

Good info you gave though I do believe your math may be flawed. Good read.

https://www.missouribullet.com/technical.php

There is a formula for optimal bullet hardness which is simple and it is worth knowing:

Optimum BHN = PSI / (1422 x .90)

The PSI of your reloads is published in the reloading manuals. Take a typical .45 ACP load, using a 200-grain LSWC bullet – 5.0 grains of Bullseye. This load develops 900 FPS and is in common use among IPSC and IDPA gunners. The reloading manual shows that the pressure generated by this load is 20,000 PSI. So, the formula for optimal bullet hardness is

20,000 / 1279.8 = 15.62

There it is! For this application – shooting a 200-grain LSWC at 900 FPS requires that you use a bullet with a BHN of 16 to 18 (round upwards a couple of BHN points for flexibility.)

I always went with the theory that leading in the forcing cone is caused by the bullet being too hard for the the velocity it is used at and leading at the muzzle is caused by the bullet being too soft for the velocity it is used at. Pretty simple but it has worked for me.

Missouri Bullets has bullets for either 38 sp. load velocities or .357 velocities

If you go with powder coated bullets, you can give up some hardness, or increase the velocity. Powder Coating helps put cast bullet shooting into another dimension! memtb

With "hardcast" alloys, bullet size/fit becomes a lot more critical. The reason I got into casting was because I bought various commercial cast products, and realized it was a crapshoot when it came to accuracy and leading.

Matching the alloy to the task helps a lot, as softer alloys obturate more easily, and thus will not allow as much gas blow-by, which is a usual cause of leading. Too-soft alloys also cause leading for the same reason, when pushed harder than the alloy can handle.

If buying commercial cast, you need to think about how fast you want to shoot them. Most handgun loads do better <15 Brinell, which is not classified as "hardcast." It helps to know what size works best in your gun, and hopefully buy that size. In your GP 100, that would be the size that snugly fits the chamber throats. And the "bevel-based" bullets typical of commercial cast, while making for easier loading, CAN allow gas blow-by, causing leading and fliers.

You may luck out, and the random bullets you buy work well. No way to know until you buy, load, shoot.

Last, I should say that powder-coated bullets cover a lot of sins, and seem to shoot better when the fit isn't best, or the alloy is too hard or too soft, and a few other smaller pieces of the puzzle. If I didn't know what size my gun preferred, and didn't know what alloy would likely be best for my application, and I didn't want to worry about the flat-base v. beveled-base v. gas-checked thing, I would avoid lubed bullets and buy powder-coated, then just load and shoot them.

10 to 12 Bhn is where I'd want to live, unless I planned on shooting lengthwise through schools.

^^^^^^^^ This ^^^^^^^ Well said! memtb

Yep. It's one of those counter-intuitive things. A bullet that fits the throat is your friend; if a bullet is too small and doesn't fit the throat no amount of extra hardness will prevent it from leading. A hard bullet that fits the throat certainly won't lead, but why waste precious tin/antimony (or the money to buy it)?

I wish I knew how that whole "hard cast" trend got started. (Well, I think I know how but will let it drop.)

Push a bullet through the throats of the revolver. If you feel good resistance with finger pressure you're ok. If they go through with no resistance get out your bore brush, you'll need it. Ignore barrel groove diameter, throats are what matter's (unless of course you have an oddball that was built with barrel groove diameter bigger than the throats in which case all bets are off accuracy-wise). You can certainly be more technical and drive a soft slug through the throat(s) and mic it and tell your bullet people that's exactly what diameter bullet you want. Additionally, make sure your expander button in the die expands the case mouth suitably too. Too small and the case itself will likely squeeze the carefully selected soft bullet down a bit, abrogating all your hard work.

Not entirely germane to revolver bullets, but I'm shooting very soft (1:20 and 1:25 tin:lead alloy) 200 grain GC'ed bullets through a .357 Maximum rifle. 1700+fps, regular old 50/50 NRA formula lube, zero leading and very good accuracy. Why/how? They fit the throat perfectly. Ditto my work with .32-40 schuetzen rifles - 1:30 and 1:40 alloys at 1400fps, and zero leading after literally hundreds of shots, again because of perfect bullet fit.

Look here too

https://rimrockbullets.com/xcart/-38-357-swc-158-gr-per-600.html

Would this be a good choice for CC in the winter with lots of clothing? (MBW heat treated, BHN 22) from the description

https://www.montanabulletworks.com/product/357-lbt-150gr-fnb-gc/

Wow, this went sideways. Not needed.

Gnoahhh, correct me if I am wrong but aren’t gas checks supposed to mitigate one of the main causes of leading with softer cast? I.E gas cutting of the base at high pressure.
As far as who started it, I got turned onto them hunting deer with a 41 mag back in the 80’s. HP’s gave very erratic performance on them critters unless you punched em within 25 yards, especially if you happened to hit bone. I can push a hard cast (18 Bnh) 215 damn near as fast as a 210 JHP w/o gas check or leading, devastating on deer sized critters out to 75 yards even hitting bone.

Certainly hard enough for any revolver load but as repeated above, Fit is king. Order the .358, larger size is your best option among the two choices.

BHN 22 is pretty much straight linotype. I can tell you from experience that it won't expand at all and behaves generally like fmj bullets. My suggestion: take a block of ballistics gel, or a thick pile of wet newspapers (where do people get newspapers anymore?), dress it in a wife beater t-shirt, hoodie, and a cheap made in China Walmart winter coat, and see what happens. I'm not being facetious, I truly would be interested in the outcome. For my purposes of shooting a couple hundred rounds per session at paper targets coupled with a haphazard approach to self defense, the soft-as-hell well fitted bullet is more than sufficient. (I don't have a concealed permit although they're easy to get here now, and my "house gun" is an old dead reliable Colt 1911 filled with 230 hardball, not at all germane to this discussion. But, again I can tell you from experience, I had more trouble with leading when I was bound and determined to make a .45 duplicate 230 fmj with a 230 RN cast from hard as woodpecker lips alloys. I was ignoring bullet fit back then out of ignorance and I said many a cuss word while brushing lead out of that barrel - fit is as important with an autoloader as it is with a revolver.)

You betcha. A plain base cast bullet can withstand a pretty fair amount of velocity/abuse, but there are definitely limits. That's where the gas check takes over. Where that demarcation falls is dependent on a lot of factors - bullet fit (hah!), type of powder (does it deliver a hard quick slap on the bullet's butt or does it impart a long slow shove), throat/forcing cone/bore dimensions and smoothness, etc.

As with most things in this man's world there are few absolutes and many variables. My point is that a fella should be aware of what makes a cast bullet tick, in general, and then apply that knowledge to specific applications while being aware that experimentation/deviation may be called for.

Cast bullet casting and shooting can be both a simple as hell pastime and a real mind f*cker. I guess it boils down to how much effort a fella wants to put into it, and what one's goals are. Just please don't accept old wive's tales, truisms espoused by the old guys leaning on the gunshop counter, and basic intuition as containing the answers. Lots of research has been conducted over the last couple decades by guys a lot smarter than me that dispels a lot of old myths - I simply pride myself with having an open mind and willingness to believe them, and then proving it to my own satisfaction.

Boy, there are countless applications/scenarios/theories/real-life observations involving handgun bullets. "Big blunt and slow vs. Big and fast vs. light and faster vs. you name it". It's all good, and makes for fun/interesting debates and reading. It boils down to whatever fits one's personal parameters/needs.

Dang too simplistic of an answer, but definitely true. 👍

You fellas ought to pay attention to gggnoah's teachings.

BHN is nowhere near as important as bullet fit. I shoot 30:1 alloy from a number of guns w/zero leading. I shoot a home brew alloy that approximates wheel weight hardness in the 2100-2200 fps range from a .30-30....no leading. Hardcast is a marketing term, and has little to do with reality.

Spend a little time and dive into this pile of info: http://www.lasc.us/CastBulletNotes.htm

Fit is it.

Frankly you can run them pretty soft or 30 plus BHN if you get the fit and finish down. The harder stuff is generally safer as PSI's go up.

I also believe strongly in the fit of the bullet to throat chambers, both in terms of accuracy and avoiding leading.

Many years ago - 1970s - I had a superbly accurate S&W 29-2, which was superbly accurate with bullets made from pure linotype in a Lyman 429421 mold, with 22 gr/2400 (the older, somewhat slower 2400…don’t try this load with modern 2400). Bullets sizes to the throats at .432”, no leading. I attribute this more to the sizing of the bullet than the hardness.

The gun loosened up and accuracy degraded at about 15,000 rounds of these loads and I sold the gun. Wish I had it back. As an aside, if somebody knows the whereabouts of #N403663, I’d pay a premium to get it back!

DD, read your link which was interesting. In no way was I trying to diss Gnoahhh on fit as it is important as is lube. My statement was that it’s this. “It boils down to whatever fits one's personal parameters/needs.”
I have absolutely no need to shoot popcorn fart 38 Special loads in a 40-44 ounce GP100 or to shoot popcorn fart 41 special in a 41 mag. Doing that doesn’t do me a damn bit of good all it does is waste components.
Your link even stated when operating upwards of 32K psi a 15-22 was justified.
So why 18 HC, because I can practice at almost exactly the velocity and pressures of 32-35.5K psi with no gas check as I would with a JHP, difference being I am practicing at 6-8 cents per bullet instead of 25-35 cents per bullet with no leading or other ill effects, that’s my parameters.
I could maybe get by with a 12 for 45ACP but what I am using works.
So that’s the skinny. Whatever works for your needs, and only the OP can decide who’s bullet and what hardness works for him.

I've noticed that there is a grand misunderstanding about "hardness" in cast bullets. Pure lead is very soft and malleable. When other metals are added, the alloy takes on different properties, one of which being "hardness". But all alloys of same "hardness" are not equal in their suitability to being shot from guns.

Elmer Keith and his cohorts who did the legwork on the development of magnum handguns only used tin as a "hardener."
But that is a misnomer, because tin, and antimony, and sulphur, copper, silver, and several other metals that will alloy with lead don't just make the resulting alloy harder. They change the properties of the alloy in varying ways. They are grain refiners, and each creates a slightly different grain structure in the resulting alloy.

Antimony is commonly used as a "hardener" now because it is cheaper than tin. It actually makes the alloy more brittle and thus likely to fracture than tin. "Hardcast" alloys contain antimony as a standard, at 6% and up by weight, and tin, usually at 2%. This makes a hard alloy, but it has drawbacks, because it lacks the malleability of an alloy that contains less antimony and more tin. Again, Keith didn't use antimony at all in his alloys in the 357 and 44 Mag. From what I've read, he saw 10% tin, balance lead, as the perfect alloy for magnum handguns.

Lyman went with 90/5/5 lead/antimony/tin in their #2 alloy, meant to be similar to 90/10 but cheaper, and the typical "hardball" alloy, with 6% antimony, was meant to mimic the hardness of it, which it basically does, but it doesn't mimic the other properties of Lyman #2, or of 90/10. People miss this point. Hardness is not a good way to define alloys. There are a lot of hardeners, and each makes an alloy harder, but that doesn't actually translate to how they shoot.

Like Dan and Gnoahhh above, as well as Elmer Keith, I like alloys with tin. The last half a dozen years, I've played a lot with alloys using less antimony and more tin. My favorite alloys have more tin than antimony, in a 2:1 to 3:1 ratio, because they seem to shoot well at many velocities and pressures while not fracturing as much when striking hard things. I can see it when shooting dirt and gongs. Some of my favorite 45 Colt Ruger loads use 94-6 lead-tin using 325-340 gr bullets at 1100 fps.

So the first thing I do with hardball alloy is cut it with pure lead, and then I add tin. 2% antimony and 4% tin, balance lead, shoots well in bottlenecked cartridges like 243, 270, 280, 30-06 at 2000-2300 fps. And by that, I mean half-inch groups are common.

All that said, if you don't want to figure all this stuff out for yourself, and you just want to buy commercial cast, powder coated bullets are your friend!

That’s exactly what he was asking isn’t it? He wasn’t asking about casting he wanted to buy from a good supplier.

But y’all carry on lots of good info but still took the train off the track.

Somebody might find value in all that babbling. I spent several thousand hours reading, researching, experimenting, casting, shooting, re-evaluating, etc. Which is a fraction of what guys like Dan and gnoahhh have spent, timewise. This site is for posterity, not just for those of us who are currently posting questions and answers.

Well sorry, but to me posterity has absolutely nothing to do with it. And unlike you I feel an honest question deserves an honest answer.
Any commercial caster SASS or otherwise offer 2 choices
1. 8-12 BNH for velocities under 1K
2. 15-22 BNH for velocities up to 1400 fps.
That’s their parameters, no in between.
Most so called HC for 357 have all been between choice 2 with 18 being the norm. Meister, Magnus, lasercast or MBC and others that are no longer around. Missouri Bullet has all the options including coated, good product and really good folks to deal with.

Now, carry on for posterity and feel safe and secure knowing that anyone that wades through this thread, the question was at least answered.

Swifty, a point you might have missed in the LASC site was that a balance between pressure and hardness is a rational objective. It requires a certain amount of pressure to obdurate any given alloy hardness, yet at the same time there are limits to the peak pressure that any alloy will tolerate. If one uses hard cast with a proper fit at modest velocity there won't likely be much problem, but on the other hand, hard cast with low pressures and a wee bit of bad fit will lead like the dickens.

I shoot cast .22, .30, .35, .40, .45, and .50. The hardest alloy I use is ~12 BHN and all of my BP guns use 30:1 or pure lead if they are ML Velocity ranges from 700-2,900 fps to date and leading is not a part of my life.

.30 caliber at about 1050 fps, BHN 9.


Simple solution? Start casting your own.

Mr Shortcut man sees a target like Dan's, and he thinks, damn these cast bullet guys are onto something here, I want to do that too. So out comes the catalog, yup, there they are, I'll order up a bunch and do what Dan does. Mr Shortcut resizes his brass with the same dies as jacketed, randomly picks a powder charge, seats the bullet, crimps the bejasus out of it. Never pound casts his throat or measures grooves. And it all goes wrong, the dream lays shattered. Old Betsy leaded to the gills. Random holes on target.
Moral to my simple ass story, if you are in a hurry, don't want to invest the time and effort to learn the ropes, buy PC bullets and use them. Please Mr Shortcut, don't trash the people who are trying to impart knowledge and skills for your benefit. If you buy a bunch of 'hardcast' bullets and they work for you right out of the gate...hurry and buy some powerball tickets too, cause brother you're on a roll.

DD I didn’t miss it, that coincides with my findings since 85. Casting was tried, didn’t want it or enjoy it. Thanks.



You sir are a prick, in my 35 year quest to find a consistent supplier of HC that suited my needs and worked, did I ever take a shortcut. I didn’t want to use GC on softer alloys which was my question to Gnoahhh which he precisely answered. This to any handgun loaders should have brought the thought, gee if I put a GC on a 12 just maybe I can push the velocity up to meet my needs. Naw, stupid thought.

So shortcut, no fugging way. In no way did I diss anyone until bringing posterity into it. You wanna ramble go ahead, but at least put some meat in with the potatoes

Relax. Just a misunderstanding, I apologize Swifty, in no way did I intend to assign you personally the role of Mr Shortcut ...strictly intended as a generic term to the seemingly endless fellows who want to buy bulk bullets and expect top notch results. Cast Boolits web answer men are especially besieged with requests, why didn't X, Y or Z work in my gun? And then the cadre of guys that know why, try to explain, slugging and pound casting the throat? Hardness, pressure, lubes etc....Crickets, the man asking the original question doesn't want to dig that deep...and that's great, jobs, family, everything demanding precious time, not everybody wants to delve deep into the hobby. They just want to shoot with ammo that realizes the potential of their gun. I probably am a prick, judging by my fan mail, but I am honest to a fault, and if I had intended insult to you, there would have been no doubt who exactly I was addressing.

I, for one, found value in that post bringing up things I'd not considered regarding hardness. And I appreciate it.

Awesome! Thanks, and a Happy Thanksgiving to you and yours!

There are a lot of words in response to your post, but to sum it up, basically any commercially cast bullet you buy should be fine; they'll all be slightly harder than you need.

The crucial thing is measure your throats with a pin gauge (or fishing lure) as matching the bullets to throat size is going to have more of an impact on leading than hardness will (not to mention the positive effects on accuracy).

It's also possible that the powder that works well for the lower powered loads might start to lead in the hotter loads. I occasionally have problems with unique doing this.

I appreciate the reference to unique - it kept me from making a mistake.
What powder would you use in hotter loads in 38spl?

Unique.

Lots of good ones on the market now. Longshot, HS-6, Power Pistol, BE-86, Blue Dot, Unique, Universal, Herco, CFE Pistol, Acc #5, and the list goes on. I really like Longshot for metering, accuracy, and speed.

Power Pistol, Longshot, CFE Pistol, Blue Dot. 2400 works well too but begins to get on the "cracky" side. Unique isn't a bad choice either.

My standard +P 38 is the 173 Keith and 5.5 grs. of Longshot, from K frames to N frames and I frame Colts.

Back at you, sir.

You mentioned good metering with Longshot...I think I'll try it in 10mm even though I poopooed it on account of what I thought I remembered when I loaded up some 3-1/2" 12-Guage several years ago. It was probably another shotshell powder that was fairly troublesome...my memory is pretty clogged thee days. I suppose Longshot truly is the choice for the 10 since there seems to be a fairly strong consensus.

I think Unique or Universal would be winners in the .38 Special, but there are probably a dozen or more choices that would work well.

Can't find Unique (my all around favorite), want to find some alternatives, and save what Unique I still have, for other purposes than the 38.

Mark, if you have Universal on your shelf, that's what I'd try (assuming you're looking at using a cast 158-grain bullet) if you're wanting to conserve a stash of Unique.

BE-86 is also a good alternative. It does meter a bit more smoothly than Unique, 'lest yer ponderin'.

RR, Universal is just scarce around here as Unique!
I'll check with oldest grandson - he works part-time at Sportsmans Warehouse in ABQ. maybe they're starting to see some trickle in.

trplem, I'm unfamiliar with BE 86, who is the maker/carrier?
Around here, I can't even find Ramshot powders reliably - so don't use them, for example.

It's an Alliant powder. Great stuff. Does really well for top-end loads in 9 and 38.

Beat me to it. Most of mine is burned up in 38 special loads.

Following the Unique-substitute discussion with interest.

Up until a few years ago I shot a lot of shotgun sports and reloaded all my ammo, buying my powder in 4-5 pound jugs. As a result I find myself sitting on a ton of Clays, Universal Clays, Red Dot, Green Dot, and Unique that now only gets consumed in tiny amounts for .32, .38, and .45ACP. It should last me 'til the end. But what if it doesn't, and I then need to consider alternatives? Knowledge is a good thing. What I really should do is convert my stash of shotshell primers into pistol primers or it'll all be a moot point.

I have been having good results with BE-86 as well as Shooters World Ultimate Pistol. The SW powder seems to work great in 38 spc loads and meters like a ball powder. I need to test it in 357 loads.