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Discussion Starter #1
I am casting using recycled plummers sheet lead. I already know this is soft for bullets. I don't know the hardness or have anything to check it with. I am wanting to know how fast I can push these before they start leading or coming apart. I have .460 285gr. fn for my 1895CB Marlin. I have only used Unique so far and my most accurate load chronoed at 1290 fps. I also have a 405 HP mold that a friend of mine is boring out .003". I had some of those that I had loaded using Rx-7. These chronoed 1711 fps with extremely heavy leading. I also have some .310 fn I won't to try in my .30-30 using Unique to keep the speed down. I guess my main question is how fast can I run this soft lead before I have problems. I've been thinking of getting some more Rx-7 to try and raise the velocities but, using Unique I only have to buy 1 powder for all my loading. Thanks for your time, JTT/NC
 

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The Hog Whisperer (Administrator)
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You would probably make life a lot easier for yourself if you would scrounge up some wheelweights, or even a bag of hard shot (find an oddball size on clearance) and mix about half and half.

I don't do much casting but that stuff sounds real soft, and I'd be surprised if you could go over 1,000fps without considerable leading.

What are you using for lube?
 

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I use a lot of soft lead for my shootin. Velocity is a measure of balance between hardness and good bullet lube.

I shoot 45/70 and 40/65 with almost pure lead up to 1240fps(chronographed) in my sharps rifles with black powder. I use a 4;3;1 mix of beeswax copha and pure olive oil which lubes the whole 32' barrel by using a grease cookie over the powder charge. I haven't tried it yet but the same might just work over a slow and bulky smokeless powder.

I have shot pure lead bullets with smokeless powder at 2100fps by using paper patching. I have a 220gr 310cal bullet which can be patched to 323 for use in a 8mm. Sinilarly a 410 can be patched up to 423 to use in a 404 Jeffery. These loads are deadly on game giving rapid expansion upon hitting solid bone. For these loads I lube the paper with the same lube as for black powder.
 

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JTT/NC

As long as your bullets fit the throat in the chamber they are used in you can get surprising velocity with soft lead and little or no leading The importan thing is the initial seal in the chamber/throat area.
This said, with Unique in the .30-30 you can make minimum power hunting loads that will prove satisfactory. Lyman lists many in both of their manuals.
I shoot a lot of soft lead also. Below 2000 fps almost any lubricant will perform fine. Heat of the day and rapidity of fire will have some affect on leading. I have shot a lot of Lymans 311291 in various .30 cal. rifles using Lee's tumble lube with good results.
Remember that for hunting (where you may only fire one round) and for shooting on the range where you have access to cleaning equipment light leading is easily brushed out.
If your grooved bullets are undersize for your throat they can be easily paper patched to increase diameter. For starters use any typing paper. For soft lead and high velocities, paper patching is the way to get good results quickly. Reloader 7 and lead bullets, greased or paper patch, is a very good combination for both the .45-70 and the .30-30.
 

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Discussion Starter #5 (Edited)
Thanks for the replies guys. I use Lee's liquid alox. I forgot to mention that I'm not using gas checks and won't. I don't have anything against them, I would just rather use wads. I also forgot to mention the .310's I've got are from a Lee mold that a friend of mine worked on for me. They were 113gr. fngc and he cut just enough off to get rid of the gas check. They are 100gr. now but he is now opening up the bands to pour .310, it was pouring .309. The 285gr. fn bullets are coming from a Lee 340gr. fn mold that he opened up from .457 to .460 and also cut down to take off a band or 2 I can't remember which. I am loading these over .45 cal Ox Yoke lubed wads. As I mentioned before he is opening my 405gr. hp mold up to .460 and I have a .456 220gr. rn mold (for ruger cap-n-ball) he is opening up to .460 to try in my .45-70 also. Thanks again guys, JTT/NC
 

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Get wheelweights, and sell this pure lead to someone shooting muzzle loader with patched round balls. they can't use anything harder, and pure lead is often hard to come by.
Humpty
 

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Soft lead will make satisfactory loads if you do not exceed a chamber pressure equal to the Brinnell Hardness Number (BHN) multipled by the constant 1440. This makes it real easy.

Pure lead is 5 BHN x 1440 = 7,200 psi - OK for Black powder loads only under most cirsumstances, but if bullets fit well and are properly lubricated you can increase the pressure limits by about 25%, which gets you to 9000 psi, which is in the range of most .38 Special midrange, indoor wadcutter loads and Cowboy Action light target loads.

Wheelweights vary from 12-14 BHN. So, taking the "worst case" for new wheelweights 12 BHN x 1440 = 17,280 psi, ideal for smokeless powder, standard velocity loads in .38 Special, .45 Colt, etc. If bullet "fit" and lubrication are just right, you can fudge this a bit to maybe 20,000 for Trapdoor Springfield loads and .38 +P

Old wheelweights or wheelweights with 2% tin, fully aged, in the "best case" = 14 BHN x 1440 = 20,160 psi, ideal for .45 ACP and .38 Spl. +P. Again, if "everything" is "just right" you can "fudge" this up to a maximum of about 25% to about 25,000, which gets you firmly into .32-40, .38-55 and .45-70 territory.

Lyman No. 2 or TaraCorp Magnum = 16 BHN x 1440 = 23,040 psi, which if everything is "just right" may work to almost 29,000 with the fudge favor, if you really know what you are doing...

Linotype is 22 BHN x 1440 = 31,680 psi, "maybe" up to 40,000 with the fudge factor, but you are really pushing it here.

Wheelweights run hot and cast so that bullets are well filled, but uniformly frosted, then immediately quenched in water, bagged while still wet and immediately put into the freezer and artificially "aged" at 0 degs. F for 28 days will ultimately attain 32 BHN x 1440 = 46,080 psi. Here is your full-up .357 and .44 mag stuff, and they will out-penetate lead core FMJ!

However, if you size a precipitation-hardened bullet, you will smear metal on and slightly below the surface, which will eventually soften due to recrystallization caused by the plastic deformation. SO once you size and load them, shoot them up right way.

Or...if the bullet cannot be shot as-cast without sizing, cast them frosty, do a good job of inspection and sorting, do your sizing, then heat treat them after sizing in a 450 degree oven for 30 minutes and water quench.

You must apply and crimp gaschecks AFTER heat treatment, because if you seat gaschecks before heat treating them you will pop the bullet bases off due to hoop stress where the edge of the GC is crimped into the heel of the bullet.

The slight softening you get around the gascheck heel due to recrystallization caused by slight deformation where the GC is crimped into the heel of the bullet seems to do no harm in my experience and may actually helps obturation in worn or oversized throats.

All of this is a really nice lab exercise for freshman engineering students in the strength of materials and in the crystalline structure of ternary lead alloys given various heat treatment. Research Dennis Marshall's articles in bacxk issues of American Rifleman in the 1980s, or in the RCBS Cast Bullet Handbook.
 

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Ed,

How does adding a gas-check to the bullet affect these calculations?
 

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soft lead bullets

JTT,
I get good results with soft lead at velocities up to about 1400 FPS.
Of course,with the paper jacket,I shoot soft lead bullets at 2150 FPS,for hunting in my 30/30 carbine.
In most cases,soft bullets will shoot more accurately then hard bullets at these lower velocities.
Frank
 

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Adding a gas check doesn't affect the calculations.

With a plain-based bullet with no GC you are limited to about 1350-1450 f.p.s. in any circumstance, regardless of alloy hardness.

The slight softening and recrystallization which is caused by crimping the GC onto the heel of the bullet seems to do no real harm in the overall scheme of things. It may actually help a little by enabling a very hard heat treated bullet to obturate a little at the base, to seal the powder gases behind it at the moment of discharge.

Most cast bullet leading is not caused by lack of material strength, but is due to improper bullet fit, and most of the time, excessive alloy hardness for the pressure level. Many commercially cast bullets use harder alloys, such as Taracorp Magnum or even linotype, which cast easily in automatic machines, and make nice looking bullets which ship well and resist damage in handling by UPS, etc.

However, most commercially-cast bullets also must be sold to nominal diameter which is a compromise in most guns, so they "may" be a bit undersided in yours. If you have an S&W .45 Colt Model 25 with .455" cylinder throats and you shoot hard-cast .452 bullets in it with light target loads, it's doing to lead, because the hard bullets can't seal the large throats, and the hot powder gases will race past the bullet, washing lead residue into the forcing cone and barrel.

You must either use a larger bullet, such as .454", or use a softer bullet of about 10 BHN which will maybe upset the amount needed.

As a general rule you can't count on bullets upsetting more than about 0.001" in a revolver, unless the pressure of the load substantially exceeds the elastic and compressive limits of the alloy, which then introduces other problems.

Similarly in rifles and autopistols, bullets should be sized to enter the forcing cone at the origin of rifling, without damage. Forget the old Lyman nonsense abotu sizing to groove diameter. Most .30 cal. sporting rifles will shoot best with cast bullets of .309-.310" whereas older rifles with worn throats may need .311-.312"

Always measure the diameter of a loaded dummy round to ensure that the maximum diameter of the loaded cartridge doesn't exceed SAAMI max. cartridge dimensions. If it does, then you need to compare against a chamber cast of your gun, ensuring that the neck if the loaded cartridge is at least 0.0015" smaller than the chamber neck, to provide safe radial clearance for the brass to expand and release the bullet. Otherwise you may inadvertently shoot a jacketed round as it yanks the neck off the cartridge case sending it all downrange and substantially raising chamber pressure in the bargain...
 
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