I dont give a darn if a boolit expands or not ,but with its hardness how will it be on barrel life? Got a chance at a wack, and sounds like it might be the thing for my speed freak loads. But I dont want to if I sacrafice barrels. Dont got any pure lead, would 50-50 with ww's be good enough to cut it?
It will shoot fine as is and the barrels will last longer than you will. Compare its hardness to that of copper, gilding metal, and barrel steel. If you have a lot of it, I would use it as is for target boolits and save the WW for hunting. Your rifles may prefer that you cut it for optimal accuracy, though, but the only way to find that out is to actually try it in them and see for yourself. Some pistols like really hard boolits, too, especially those with higher working pressures like 9mm, 40S&W, and 10mm.
Born OK the first time.
By all means grab it. Air cooled WWs aren't a whole lot harder than pure lead. You are in a unique position of knowing exactly what you have and can alloy it accordingly.
If it is genuine foundry type (printers use these terms rather flexibly at times), by mixing it one to one with WW the outcome is linotype that is slightly high on tin. Since there is quite a lot of alleged linotype around that is 2% tin where it should be 4%, the lino you'd make yourself would end up being better than most.
Depending on price, foundry type is a very useful item to have around - you can mix it in when you want to harden up a wide variety of alloys.
its 400 + pounds for the 15$ of fuel to go get it
Originally Posted by charger 1
Charger,
It's not the hardness, it's the antimony content that is in excess of the tin content. Antimony is a rock in nature and is EXTREMELY abrasive. I have some down stairs that has had the spines washed so it can be smelted in easier.
It's sort of funny really. Many ol'timers would not shoot a bullet with antimony in it if their life depended on it. Only pure lead and tin for them. And many of these guys pushed 2700 fps too.
Now we have come full circle to include me. Only rock hard is accurate and we need to shoot a rock if we want to go over 2000 fps. Funny how time works.
Bass, I too like the idea of keeping the antimony as low as possible while getting the required result, but I'm finding it very difficult. In my case I may have made it unnecessarily difficult for myself by wandering down a blind alley - I've been water-dropping my bullets, and have just learned that the result has been a spread of ten BHN numbers in hardness of allegedly identical bullets, cast in the same batch. Possibly my highly variable group sizes have been caused by a random mixture of bullet hardnesses within each group; I can easily investigate that by switching to air cooled bullets and using antimony content to control bullet hardness. However that still leaves me with a problem or two in trying to match your success with 14 BHN bullets at high velocities. One of these is that my 30-30 only has a 20 inch barrel, and with a slow powder I'm just not going to get much velocity before the bullet exits the barrel. The other is that the slow powders seem to be generating lots of hard carbon fouling, which is bad enough in a deeply rifled barrel, but is likely to be just plain disastrous in a microgroove barrel with its extremely shallow grooves.
Can you give me any pointers on getting out of this mess?
Geoff
This may be off topic but I am shooting a .38-55 Marlin with a .379 bore and chamber that wont allow .380 or larger bullets. Smaller bullets do bump up and shoot very well. In reading about this delima I came across several articles that said .375 jacketed bullets shoot well in these guns because they bump up and fill the bore. Huh?? Jacketed bullets run about 100 on the BHN scale and softer cast bullets that bump up run about 10-12 BHN. I must be missing something. Can anyone help me out here?
Jackets run 100 BHN. How hard are the cores?
To put it simply, condoms stretch to fit the contents.
Now I'll probably fall foul of the thought police. Oh well.
Bore rider bullets will shoot good provided there is enough engraving to hold them onto the lands. Boolits, on the other hand, must have all of the land support available, and therefore should be groove riders to do their best. And, yes, all bullets/boolits do obturate to some extent; the amount of which is dependent upon the factors you already know. Besides that, that same projectile will contract from that obturation, depending on its toughness, which is a simple way of saying elastic quality. So, to keep a "small" boolit permanently obturated, the pressure must be kept up, or change the boolit material to yield permanently at the given pressure. ... felix
felix
I'd like to try getting 20+bn by the ingredients of the alloy as opposed to the water or heat afterward
if you were in michigan wed be racing there to get it!!
Geoff,
Water dropping for me, yields bullets all over the spectrum as well. I heat treat in an oven when necessary for consistency from bullet to bullet. If done after sizing, the hardest / finest bullet of the correct diameter for HV work is created. Hardness can be controlled by temperature, time, and mix formula. HTed or hard bullets make you vulnerable to the dreaded lube flier. If you want a 15-16 BHN bullet, then mix WW 50/50 with pure lead and HT it in the oven. You can play around with temp and time and get 16-20 BHN depending on all the variables.
I believe that the secret to accuracy with ANY lead bullet is to go as soft (or hard) as necessary to produce the velocity level of interest. Or .... as Marshall said, best accuracy occurs just before leading begins. Because you have no excess lube to act as fouling at this point. Lube acts as a hydraulic fouling that will actually size down bullets. Once this occurs, you have less rifling griping diameter to maintain seal and drive contact. This flies in the face of those that believe that lube is the sealer. It's a fouling.
But realistically, as with Black, a bullet must be able to handle fouling without sizing down or deforming. Bullet design plays a key part in higher velocity work. I use a one diameter bullet with a reduced diameter nose, just enough to provide a scraper edge to act like a cow catcher on a train. Sort of a slight semi wadcutter for rifles if you will. It helps to eliminates lube as a variable in cold weather for me. Usually when my bullets fail, it is because they are not capable of handling fouling at high velocities, as lead is only so strong regardless of how wide the drive band is.
So improve barrel condition, pick a slipery lube and then go as soft as necessary or use as little lube as necessary to attain enough velocity to reach the accuracy node for your barrel.
Does that help?
Bass, that is even more complicated than where my thoughts were previously. I want to get a reasonable MV from my 20" 30-30, without torturing the rifle and with consistent and decent accuracy. So far, the best velocity with reasonable group size came from Varget and Lee C308-170-F, but the group wasn't that small (1.2" at 55 yards) and the powder charge limit seemed to be 30 grains, which from other people's data seems to give 2000 FPS. Options for getting to 2100 FPS seemed to be a harder bullet plus more Varget, or a slightly slower powder. Since my bullets already averaged 19 BHN, I'd mostly be hoping to tighten the group by reducing hardness variability rather than increasing the average hardness. Maybe by shooting pure linotype - mine tests at 19.6 BHN - I could add a few more grains of Varget and reach my objective. I think I need to give that a try, anyway.
The slower powder route would have me shooting W760, but experiments to date have given poor accuracy if I use enough powder to get reasonable burning. Looks to me as if I'm running out of bullet strength again - this time because W760 won't burn well unless pressures are high. There is one trick I haven't tried: using AR2209, which has the same burning rate as W760 but as far as I know doesn't have its requirement for high pressures. That might let me get just a bit higher in velocity than Varget, with the same bullet hardness. However I still think I'd be needing considerably more than 15 BHN to get say 2100 FPS with the C308-170-F bullet.
Hence I'm not seeing an opening here that has me using the soft bullets you prefer. The reasons may relate to the short barrel and shallow rifling that my 30-30 happens to have. The problem does not seem to be bullet design at this stage, since I'm trying to get more velocity without the bullet collapsing, rather than improving the group size. Once I've got the velocity, with a bullet hardness that only just supports that pressure level, I'll be at the point where I need to focus on improving group size - and from what you've just told me, lube management will become crucial.
Once I know what bullet hardness I need, I have a choice of achieving it with antimony or with heat treatment. I have objections to both, but as a former Australian prime minister famously said, "Life wasn't meant to be easy."
I dont know . when I fire those 480's outta the lott the cloud of lyman moly lube dispersing out the muzzle temporarily fogs everything out of view like a BP on a cold day. And never flier one...But I will agree with one thing. I have found with my limited experience that things work better if pounded to the upper limit of pressure as opposed to the min. I've become a firm believer of the 1432X bnh as an absolute min pressure. Calculating the RPM of that lott also makes it a looser at close to 140 G's, but apparently that formula doesnt take into effect the near perfect concentricity of some custom molds
NRA cast bullet supplement says that mixing 1 part foundry type to 2 parts wheel weights equals linotype. I have a good supply of FT, and the only downside to it is the copper content. It tends to clog up the pour spout. The remedy is to heat the pot to 750 and then drop it back to 600 for 15 minutes. The copper will seperate and can be skimmed off.
First, using the US specification of foundry type (http://www.apa-letterpress.org/T%20&...0castings.html) that 2:1 alloy would only have 10.5% antimony, while linotype is 12%. As you say, US foundry type sometimes contains copper, which can be a problem.
The Australian trade definition of foundry type was 10% tin, 20% antimony, no copper, and was way more convenient for bullet alloying. However when I hardness test the large pile of ingots of the stuff I have, the result is all over the place. It was supposed to be 33 BHN, but is anywhere from 18 on upward, so it appears the printers used whatever alloy fell to hand. It all appears to be good stuff, and makes lovely castings, but if you want to get any specific outcome you need to hardness test the ingots and mix them to give the alloy you happen to want. No big deal I guess.
You may find that American foundry type turns out to vary just as much as Australian foundry type. I recall 454PB said he had a huge batch of the stuff, and found that each piece was a different hardness from each other piece.
Yes, I tested a hand full of linotype still in letter form and found a wide variation in hardness. I'm beginning to think that printers took more liberties with alloys than casters do.
I may not be as picky as some, but I want the linotype for it's tin content first, and it's hardness next. I use 75% WW and 25% linotype for my magnum pistol boolits with good results. While I've used straight linotype for rifle boolits, I've more recently been using a 50/50 mix of WW and lino, and even 50/50 pure lead and lino. The pure lead and lino hardness tests up around 18 BHN, and cast a very nice boolit. I'm in the strange position of having more pure lead and linotype than wheelweights.
I'm kind of in the opposite position - I hardness tested ten ingots of the local WW a couple of days ago, and found an average hardness of 14.9 BHN (standard deviation 1.7, probably because I throw in the stick-on weights unless they are awfully soft), minimum 11.0, maximum 17.2. My current explanation is that the local Australian WW must still be 6% antimony, as it was in the US until a few years ago. So, I have to go out of my way to produce an alloy of less than 15 BHN air cooled. Lucky I'm not into muzzle loading - I'd have to go out and buy lead.
Right now I can't understand how you'd get 18 BHN from a 50-50 mix of lead (5 BHN) and lino (22 BHN). Sounds as if you've slipped in some of your foundry type.
Geoff
Posting Permissions
| BP | Bronze Point | IMR | Improved Military Rifle | PTD | Pointed |
| BR | Bench Rest | M | Magnum | RN | Round Nose |
| BT | Boat Tail | PL | Power-Lokt | SP | Soft Point |
| C | Compressed Charge | PR | Primer | SPCL | Soft Point "Core-Lokt" |
| HP | Hollow Point | PSPCL | Pointed Soft Point "Core Lokt" | C.O.L. | Cartridge Overall Length |
| PSP | Pointed Soft Point | Spz | Spitzer Point | SBT | Spitzer Boat Tail |
| LRN | Lead Round Nose | LWC | Lead Wad Cutter | LSWC | Lead Semi Wad Cutter |
| GC | Gas Check |
Reply With Quote