Brinell hardness of wheel weights and linotype mixture?

[dgang]

Prepping to get into casting bullets. I have two bars of lynotype and a couple of hundred pounds of fluxed wheel weight ingots from years ago when I was making shot on a Littleton shot maker. I'm planning to make a 50/50 mixture. Anybody knowledgable as to the Brinell hardness I can expect?
Thanks in advance and good shooting' to ya'.

 

[oley55]

did you try looking here: http://www.lasc.us/CastBulletNotes.htm

I did a quick glance and didn't see you question/answer pop out at me, but there is so much info I may have glossed over it.

 

[BBarn]

Hardness of that mix would be about 16 BHN. With the level of antimony being fairly high from the linotype, bullets will cast a bit lighter and will shrink a bit less than those cast from straight WWs.

 

[dgang]

Thanks for the link. I was told a little more tin would help with shrinkage. Will try the 50/50 as BH 16 is what I'm looking for, pretty fast (1200-1250 fps) and little leading.

 

[FrankenMauser]

You don't need BHN 16 for that velocity, just a bullet properly sized for the firearm(s).
Don't waste the Linotype unless you have to. It's a precious commodity.

 

[dgang]

I will keep that in mind. May start with 50/50, then drop to 40/60 and so on until leading appears and then back off. Thanks for the input.

 

[Unclenick]

Keep in mind that Elmer Keith came up with the 44 Magnum loads using 16:1 lead:tin, which is about BHN 11 or 12. As FrankenMauser said, you want something that fits your chamber(s).

There is a spreadsheet calculator for alloy hardness you can download from the Cast Boolits site.

 

[dgang]

Didn't know that Keiths load was that hardness. Maybe just start with the 40/60 mix and work down according to results. I've looked at that link and it is useful for developing mixtures but doesn't help in determining how the alloy will react with different pressures I'll be using. Lyman's cast bullet data shows linotype and #2 alloy, which I understand is pretty close to a 50/50 mix, in loads for different velocities. Just something I'll have to experiment with along with lubes, temperatures, mold material, etc. Thanks for the heads up.

 

[USSR]

Didn't know that Keiths load was that hardness.

Yep, the commercial casters have done a good job of convincing guys they need an overly hard bullet.

Don

 

[dgang]

Talked to Frank at Oregon Trail Bullets and he said just about the same thing. Laser Cast use to state their bullets were 21-24 BH. When he took it over he found they were about 12-14 BH. That is what they claim now. He might be an exception to the rule. Take everything with a grain of salt.

 

[Unclenick]

Dgang,

Well, if you have a revolver with the bore constriction that is common where the barrel screws into the frame, you may find you get better accuracy from softer bullets that do upset some. Upsetting back up to bore diameter under pressure after passing through a constriction cuts down on the gas cutting that causes leading. If you are shooting about anything else, hardness offers a means of resisting pressure deformation. That becomes important with rifle or other higher accuracy loads. The problem is that for 9mm at 33,000 psi, observing this limit already has you shooting Linotype. You can try doing that, just to see what it does to accuracy for you, but for lower pressure pistol loads you find BHN 16 handles about 20,000 psi. Super light 45 Auto target loads at 14,000 psi will work with BHN 11 without deformation. For magnum revolver loads, it just doesn't seem cost effective, and you are not shooting sub-moa groups with them, for the most part.

The late Richard Lee's book, Modern Reloading, 2nd Ed, on page 134 has a table of BHN vs. firing peak pressure. He set that firing pressure -10% lower than the alloy deformation pressure to provide a margin that allows for shot-to-shot pressure variation. It turns out to be a simple linear equation. To satisfy the zero deformation condition, your alloy needs to be:

BHN = psi/1280

or

psi = 1280×BHN

Edit:remove the irrelevant decimals.

 

[dgang]

I am looking to load 158gr. and 170gr. .358" bullets @ 1200-1250 fps from a 4" GP100. Lyman puts that at 40,000 CUP. Not sure how that equates to PSI but would think it is close to max pressure, around 34,000 PSI. If I follow what you are saying and what I have read, the bullets requires a higher BHN than 12 but not close to linotype. Maybe 15-16 BHN to allow swelling to fill the the lands and grooves but not too soft to produce leading by smearing, if that is a proper term? I will look at Lee's book. Thanks.

 

[Unclenick]

34,000/1,280 = BHN 26.5

So you're not going to directly prevent pressure deformation unless you spend a lot on alloy. Fortunately (and I was remiss in failing to mention this) there is another out: gas checks. If you put copper gas checks on the bases of your bullets, their copper hardness is about BHN 60, IIRC, and you won't be deforming that, as it should withstand:

1280×60 = 76,800 psi

 

[dgang]

I'm guesstimating the pressure would be 34,000 PSI from data that I have read, really don't know. I do want some deformation as to make a seal for the gas. Will have to experiment. I have thought of gas checks but really just wanted to start gathering the necessary equipment and now and get ready for warmer weather since I will be working in an unheated garage. It is 15 degrees here, only reload inside. So, rather than get too carried away I thought to keep it simple until I can produce some boolits, load some up, shoot the rounds, see the results, and go from there. Thank you for your input.

 

[Dufus]

IMO, how snug the bullets fit the cylinder throats is more important than hardness. For best results, size your bullets to fit snug into the throats.

Second in importance is bullet lube. Use one made for the velocities that you intend on shooting. I know a lot of people use their homemade gunk, but it is inexpensive enough that I buy it from White Label at www.lsstuff.com

Then bullet hardness comes into play.

I use nothing harder than wheel weights and most of my handgun bullets range from 8-12 depending on caliber.

 

[USSR]

IMO, how snug the bullets fit the cylinder throats is more important than hardness. For best results, size your bullets to fit snug into the throats.

Yep. I regularly shoot .38 Special +P loads (940fps) with bullets with a BHN of 7 - 8 BHN, and .357 Magnum loads with 11 BHN bullets. Fit is King!

Don

 

[Unclenick]

We still don't know what kind or caliber of gun these bullets are going in.

For revolvers, fit the bullet to the throats even if that means going +0.005" over groove diameter. Don't be surprised if the chamber throats aren't all the same diameter. Reaming them to a uniform diameter is standard revolver accurizing practice. Those throats must be larger than your barrel groove diameter by at least +0.001" and preferably +0.002" for cast bullets. My best shooting 44 has chambers +0.0035" over its barrel groove diameter, and that's the size I make the bullets. If you have a bore without constrictions, harder bullets that are a thousandth or two oversize will work fine. You can firelap constrictions out. If you have constrictions, soft bullets often shoot best, but nothing beats a constriction-free bore. The caveat: many oldtimers felt tapered bores that gradually narrowed half a thousandth to a thousandth tighter going from breech to muzzle were the very best for accuracy. It is constrictions that are narrower than the muzzle before the bullet arrives at the muzzle that are the troublemakers.

For a conventional semi-auto pistol barrel, load lead bullets into the cartridges long enough that the full bullet diameter gets into the throat when chambered. Occasionally you find a bullet design long enough that you can't do that and still have the finished rounds fit into and feed from a magazine. But as long as they fit and feed, you can load them out to make contact with the lands when chambered, and for lead bullets, that practice seems to produce the best accuracy and the least leading. But it also means you don't want the bullets sized wider than about -0.001" under the throat so they fit in during feeding. You may need to slug the throat with a soft lead ball to measure that diameter.

 

[reddog81]

How big are the two Linotype bars? You’ll run out of Linotype pretty quickly if you’ve got hundreds of pounds wheel weights to mix with.


FWIW wheel weights do not have a consistent hardness. I’d had a source of wheel weights that had 1, 2, and 4 ounce weights for semi tires. These large weights were dead soft and probably close to per lead. Some of the little 1/4 ounces weights are made so hard they can be difficult to distinguish from steel.

 

[Sure Shot Mc Gee]

I've never heard anyone deliberately mixing a \\50/50// W/W lead and lino together I have seen a W/W lead and lino mix stating a much smaller amount of lino used. Maybe a call to a Caster {manufacture of ball or bullets} or Roto Metals might have a confirmed answer to your question/s.

 

[Road_Clam]

And then there is the variable factor of how are you actually measuring your BHN ? I have the Cabin Tree lead hardness tester and while it works very well in theory it can be a challenge to come up with a consisteient BHN number within a single ingot. I purposely bought certified 99.9 % pure lead, and certified 20:1 alloy from BACO soley for testing BHN with my Cabin Tree tester. This way i have an accurate and consistient comparative baseline measuement to test my other purchased unknown hardness lead.