Help With Bullet Alloy

[thedane]

I have soft lead and I have linotype. I want to make an alloy that I can use up to magnum handgun velocities (1300-1400 f.p.s.). The linotype makes beautiful bullets but it is too hard and brittle.

I don't want to add anything (i.e. tin), if possible. From what I've read, an equal mix of linotype and soft lead should give me about 2% tin, 6% antimony and 92% lead. Do you think that will work or should I decrease the amount of lead?

 

[Jstot]

The half and half, 92-6-2 alloy is wonderful stuff to cast with but it is still pretty hard. I've shot a lot of wheel weights with about 1% tin added to 1300 to 1400fps so you might stretch your linotype by mixing it 1 to 3 or 1 to 4 with the lead. You won't be disappointed casting the 92-6-2 alloy until you have to buy more linotype!

 

[Tell Sackett]

Read this article. Cast bullet alloys, characteristics of CB alloys, maintenance of CB alloys

It says that 11BHN to 30BHN was fired in a 357Mag @ 1550fps, all with no leading. Here is a quote "These were top end 357 loads with a 190 gr. bullet at 1550 fps proving (in my mind at least) that bullet fit in a properly dimensioned firearm is far more important than alloy BHN."

This has been my experience as well. It is fit, then fit, then fit and last but not least, fit, that prevents leading.

Elmer pushed his lead bullets pretty hard and they were much softer than most folks think will work well. His hardest loads were 10/1 lead to tin. No wheel weights, no Linotype, just lead and tin. His famous 44 loadings were 16/1!

I use a mix of Linotype to wheel weights for some loads. Usually 9/1 or at most 8/2 lead to Linotype.

FWIW

 

[thedane]

I used up the last of my wheel weight ingots last week. I don't really want to scrounge wheel weights anymore, but I always thought they made great handgun bullets. I have about 120 lbs. of lead and maybe 30 lbs. of linotype. Per the above article, it seems that if I mix 1 to 4 linotype to lead, I'm close to a wheel weight alloy of 1% tin, 3% antimony and 96% lead. Does this sound correct?

That may be what I'm looking for.

 

[epj]

If you want your bullets harder than they come out air cooled, try water dropping. Assuming there is some antimony in the alloy and there will be if you add linotype, the bullets will become significantly harder with water dropping. I water drop as a matter of convenience. I am using a 6 cavity mold, and I can speed up the process considerably if I don't have to wait for the bullets to cool as much. As others have indicated, proper fit trumps hardness. If casting for an autoloader, hard bullets are sometimes desirable to prevent deformation during the cycling process.

 

[Snapping Twig]

Straight WW for me too, but I'd say 1 to 4 for a lino/lead mix.

Proper sizing (.001 oversize) and a good lube go a long way.

Try White Label BAC - low smoke and good up to rifle velocity. Inexpensive too.

 

[BruceM]

I would like to know when the notion that straight linotype is too hard and brittle comes from. It may be unnecessarily hard and can be cut but too hard? I think not. IMO, a bullet is too hard and brittle when the driving bands are stripped during engraving at the velocity a particular load is achieving. That said, I mix three ingots of wheelweights with two ingots of linotype. It produces an alloy of sufficient hardness to produce bullets which will not lead up to velocities of 1400 fps when sized & lubed correctly without gaschecks.

I've never been a fan of having water around a casting furnace, especially after I nearly smoked my face off many moons ago when a very tiny droplet of sweat fell from my brow into my RCBS Promelt. I can still see it falling in slo-mo. It takes a little longer to heat treat, if needed, in an oven but it's safer.

Bruce

 

[OKFC05]

I would like to know when the notion that straight linotype is too hard and brittle comes from

It comes from shooting relatively light loads in which the bullet does not obturate, but leaks hot gas under the bullet and thus leads the forcing cone/back end of the barrel.
Not a problem with .357 magnum loads but quite common with standard .38.

 

[epj]

I've never been a fan of having water around a casting furnace, especially after I nearly smoked my face off many moons ago when a very tiny droplet of sweat fell from my brow into my RCBS Promelt. I can still see it falling in slo-mo. It takes a little longer to heat treat, if needed, in an oven but it's safer.

Bruce

I have the casting furnace on a table, and the container of water on the floor, a good two feet or more BELOW the top of the casting furnace. Don't think there is much chance of the water reaching the pot.

 

[thedane]

I have "read" that linotype is too brittle and that it can shatter on impact with a hard object. My personal experience is in trying to size it. I found it very difficult to get through my Lyman 450 sizer. Wheel weights are no problem.

I have been using a .429 sizer for 44 mag/special and .451 sizer for 45 Colt. The Lyman casting manual states that you should size as close to bore size as possible or a little more. This seems to work for me. However, most commercial castings for 44 mag are .430 and .452 for Colt 45/.45 ACP. That makes me wonder...

Also, based upon the alloy, the bullet size varies after sizing. The harder the alloy the greater the before and after sizing diameter.

 

[BruceM]

"It comes from shooting relatively light loads in which the bullet does not obturate,"

If the bullet is sized properly, there is no need for an soft, undersized bullet to "obturate" in order to seal the bore. If the bore is sealed by a correctly sized bullet, it's sealed.

"I have "read" that linotype is too brittle and that it can shatter on impact with a hard object. My personal experience is in trying to size it. I found it very difficult to get through my Lyman 450 sizer. Wheel weights are no problem."

Unless you are making armor piercing ammo or heavily into metallic silhouette, bullet shattering is a non-issue. To be honest with you, the only shattering problems I'm familiar with are those encountered by silhouette shooter using heat treated bullets are very high velocities. If you have to "reef" to get your bullets through your sizer/lubricator, odds are overwhelming that the as-cast diameter is already way too large to begin with. Sizing through a sizer/lubricator is used to make bullets concentric, not swage oversized bullet down to a required diameter. This is because the process of swagging destroys the hard surface of the driving bands. The bullets are not of equal hardness through and through. People who water drop or oven heat treat bullets know this or should.

"Also, based upon the alloy, the bullet size varies after sizing. The harder the alloy the greater the before and after sizing diameter."

Actually, the harder the alloy, the larger the as-cast diameter is from the same mold.

These concepts are covered in detail in both the NRA's Cast Bullets Handbook by Col. E.H. Harrison and Lyman's Cast Bullet Handbook.


Bruce

 

[GypsmJim]

I started casting in 1975. Back then my Father was a printer and I had a friend that was a plumber so I was golden...LOL.

I'm fuzzy on the source, but I read that a 3:2 lead:linotype blend was equivalent to Lyman's classic #2 lead formula. I used that mix for 20 years until my Dad retired and I couldn't get linotype any more.

I experimentred wit 100% type in rifle bullets and frankly couldn't see much difference. I went back to the 3:2 blend to conserve the type.

About 15 years ago I switched to 100% wheel weights and have had equally good success. That's my staple now. When I heard that lead WW would eventually be outlawed I stocked up from local tire shops and right now I should have about a 30 year supply of lead.

Anyway, short story long, I would suggest 3 parts to 2.

 

[Tell Sackett]

Linotype brittle? Well, maybe. Harder than wheel weights? Oh yeah.

Like Bruce says, if a bullet fits, it fits. What I have had happen though when purchasing cast bullets is I get a bullet that I want to drive @700fps and it is .001" too small for the bore of my gun and is harder than Linotype(figuratively speaking).

When you have those three things line up, look out, you are going to get leading, period. Get the size up to .001" over cylinder throat size, which should be bigger than bore size, and it should work fine. It may not because of some other situation, such as rough bore, bulged barrel or a thousand other things, bad lube may be one.

What you will get with a bullet that is too hard for the task your loads are designed for is this: Cost. The cost of the bullet is much more expensive than one that is designed to shoot at lower velocities. The reason? The cost of the additives in the alloy.

Why use Linotype when a straight (nearly) lead bullet will shoot fine at 650fps to 800fps? Does the paper or steel target know it got hit with something soft? No. Why waste the harder material then? Save it for the hunting/self defense rounds you are going to make up. Save them for the auto that will not feed bullets that are too soft. Save it for those types of loads.

As for size and hardness, that nail has been hit firmly on it's head. If you have a mold that is casting too small, make a harder bullet and shoot at as cast size. You may be surprised to find that the alloy will work just fine then!

As for the size being the only thing that matters though, it isn't. Alloy still matters. Take for instance the swaged bullet. Softer than soft can be. It may fit your barrel and all like a proverbial glove. Drive that baby too hard and you aren't going to like what you find in your barrel.

Maybe what Bruce is trying to say is this. A bullet can be too soft to work even when sized correctly but one sized correctly cannot be too hard. I hate to speak for him but thought I would paraphrase it like that.

 

[leas327]

I try to thin out the mix and use a little lino as possible. With all these new fangled computers and lazer printers we will be competing with museums and antique dealers for the lino and mono pretty soon. Proper bullet fit is the biggest part of velocity and not leading the barrel. I am new to casting but have followed this advice and it has served me well. You can mess around with water dropping. It works but some people don't like it because of the water near molten lead. If you keep the bucket on the floor and make a little carboard chute that leads to it you can eliminate the risk. It looks like you are going to have to experiment and find what works for your application. That is part of the fun.

 

[OKFC05]

A bullet can be too soft to work even when sized correctly but one sized correctly cannot be too hard.

if and only if the cylinder throats are at least .001 over the bore size

I love absolute statements, but I fear we are doing the neophyte lead loader a disservice by leaving out the part about the cylinder throats.
If someone has a revolver with throats the same size or smaller than the bore, he cannot solve his problem with "correctly sizing hard bullets," and we should not leave the impression that he is incompetent if he can't.

For some people who have this mismatch and just want to shoot some lead bullets at 750fps, they can get by using softer bullets that will obturate sufficiently.

Ideal? No, but it is cheaper than recutting cylinder throats just for some plinking rounds.

 

[mack1]

I,m just a novis caster but like others have stated fit is far more important than hardness. I can push 1/2 ww 1/2 lead to 1250 fps in a 4" 686 with no leading SPG lube. I also think softer lubes work better at this pressure level. I've had a lot of trouble with leading with commercial cast bullets in 38 sp loads I think because they are to hard. Look at cast boolets forum there is a welth of good info on any casting question you can think of.

 

[Tell Sackett]

I think we agree

if and only if the cylinder throats are at least .001 over the bore size

I love absolute statements,

OK,
Read my entire post above. Here is what it had in it.

Get the size up to .001" over cylinder throat size, which should be bigger than bore size, and it should work fine.

I guess I already qualified mine and Bruce's statement. You raise a good point to use swaged HBWC for those kinds of firearms. The softer skirt will size down and then back up to get accuracy and eliminate leading. I could be wrong but I don't think you could get a good cast bullet with lead that soft. You need some tin to get good fill out, and something soft enough to do as we are talking about wouldn't fill out too good. I know there are exceptions. Hot moulds and all, maybe.

Anyway, we have given the OP plenty to think about and we can all agree on a couple of things.

As for having leading with undersized cast bullets. I have several rifles that I try to get higher than normal velocity out of. I succeeded on a bunch of occasions, failed on others. 1900fps from a 45Colt or 44Mag would seem to be pretty impressive in my book. Maybe not yours, my book is small!

The only thing I changed to get that kind of velocity was size. Oh, I tried a lot of other things, all the things we have talked about as a matter of fact. Then, in the end, it all came down to size. Well, size and bearing surface, I guess. Bigger bullet with more bearing surface. Same powder, same charge, same lube, SAME ALLOY, wheel weights & Linotype, 8lbs clip on/2lbs type metal.

FWIW

 

[BruceM]

I would like to add one thing about cylinder throat matching.

If there is a significant mismatch between the bore diameter and the cylinder throat diameter, it will be very difficult to get accurate cast bullet loads at high velocity. Leading problems in this instance are usually unavoidable regardless of how much messing around you do with the alloy. Also, it's pretty impractical to be varying alloy when load velocities rise or drop a couple hundred FPS. It's far easier to control the size and keep everything else the same. If you do run into a gun with major dimensional mismatches, you will probably need to relegate it to jacketed bullets, invest in some minor gunsmithing or trade it off for one which will provide better results.

Bruce

 

[thedane]

There is always good information to be had on this and other forums.

As far as brittleness of linotype, I have read this in many places. T. Sackett referred me to an article on the L.A. Silhoutte Club Website. If you go to this link on the same website: Cast bullet Handgun Hunting in Africa you can read about experiences with linotype brittleness. There are other articles that document this.

We can all continue to learn...

 

[whelenshooter]

The L.A. Silhouette web site has a lot of cast bullet articles by Glen Fryxell. That guy really knows his stuff when it comes to cast bullets! His articles are well worth the time it takes to read them! I'm surprised he doesn't write for some of the better firearms magazines. I haven't seen any of them publish stuff as good as his about cast bullets.