Velocity and leading?

[ShooterAZ]

I have been casting and loading for .38 Special and .45acp, with plain base TL boolits. I have been using the Recluse 45/45/10 lube with very good results for these lower velocity loads. I just ordered molds to load for my SBH .44 Mag, and I'd also like to start loading for .357 Mag in my Contender and S&W 686. The alloy is 2-6-92 Hardball. My questions are...at what velocities do I need to be concerned with barrel leading? Would Rooster Jacket be a better lube for higher velocity loads? Any other recommendations? Still learning and enjoying this forum tremendously! Thanks...

[btroj]

Within reason velocity has little to do with barrel leading.
I have had leading with loads going 1000 fps, I have had none with loads going 2000 fps.
Have a bullet that fits, good lube, and appropriate hardness and you won't have issues with leading in handguns.
You have a hard alloy, be careful with liter loads as it may well give leading. Shoot a light load thru a tight cylinder throat into a big barrel and you get lead. Thread choke will also lead more with a hard alloy and light loads.

As you can see, leading is caused by many factors beyond velocity. Handguns can lead at any velocity that is reasonable but they also can shoot very well at the same velocities. The ultimate key is to find that combination of factors that works well for your gun. The ones to look for most are bullet fit to the throat, a decent lube, and a gun with measurements that work well with cast.

[ku4hx]

My favorite alloy is hardball, or a close approximation thereof, and in my SBH I get no leading using LLA. From my gun's 7.5" barrel, my top load clocks at a hair over 1,600 fps for a 240 grain SWC. The same is true for softer stick lubes, I just no longer use them.

The causes of leading are many and varied but generally boolit fit is of prime importance. And what fits your gun may not fit others ... slug your bore and chambers.

I've never tried Rooster Jacket since I found no need to. Having no volatile solvents yet being a liquid tells me it's likely water based. Nothing inherently wrong with that, it just sounds a lot like water based paint to me.

As too velocity and leading, there are postings on this site claiming 2,000 fps with no leading. My experience tells me that's definitely possible. Threshold velocity for leading is very likely a gun-specific situation. That being said, I've fired what must be a ton of .38 Special pure lead boolits at around 750-800 fps with no leading. So that's my velocity threshold.

[geargnasher]

Like was said, within reasonable limits, velocity has squat to do with leading. Fit has the most to do with leading, particularly dynamic fit as the boolit passes through all the dimensional variances of the gun. If the dimensions get small, then large (as in past a restriction like thread choke) the dynamic fit is compromised, gas will leak past the boolit, cause erosion (gas cutting), and deposit huge amounts of lead in the barrel.

Lube has a slight effect on leading, as it's supposed to aid the gas seal (obturation) of the boolit in the bore, but if the dynamic boolit fit is too poor no lube can make up for it, gas pressure will blow the lube (and some lead particles from the boolit) out ahead of the boolit through any leaky spot it can find, and you'll get lead in the bore no matter the lube.

One important thing not mentioned yet is powder choice. Especially in a revolver, powder burn rate can have a drastic effect on whether a load leads or not, it has to do with how tighly the boolit is sealing when pressure peaks. If the boolit is in the middle of the cylinder gap when the pressure peaks, you might get leading on the cylinder face and frame. If the pressure peaks when the boolit is fully engraved in the barrel, you're good to go. If pressure peaks just as the boolit is breaking the crimp, it can lead the cylinder throats if the fit is too sloppy there. Not always in any of these instances, but probably.

The name of the game is obturation. IF IT LEAKS, IT LEADS. So the load must be balanced with maintaining boolit-bore seal in mind. That means selecting a powder and working up a charge that will work with, rather than against, boolit strength, selecting the right primer to go with it, and using a lube that has the correct lubricity and viscosity for the particular application. It also means the revolver must be at least close to dimensionally correct, and that static fit, the way the boolit fits the gun when you load it, needs to be right also.

When you build a load you need to have your ultimate goal in mind, and start with an alloy that will do that, or work within the ideal range of what you have, and select the remaining components to match. You need to realize that alloy is not a fixed quantity, though, and depending on the gun and load, a wide variety of alloys will perform a wide variety of tasks very well, or not. How do do all this? Common sense and experience gained from shooting a lot of loads that didn't work so hot. If you are very specific, we can help you a lot narrowing down what components to try and how to fit them and load them. Remember, every gun is different, so ultimately it's up to YOU to try different things and find the best answer for you and your gun yourself at the range.

If everything is right, you can shoot PB boolits with excellent accuracy, no leading, and at velocities that will amaze you. If one thing is wrong, it all goes south, and quickly. That is why we can't give you the number you were looking for.

Gear

[ShooterAZ]

Thanks for all the replies. I have a LOT of different powders to try. I am an experienced reloader, but casting is quite new to me. For me, reloading and load development has been half the fun, so I will get to work on experimenting. From many thing I have read, 2400 might be a good place to start for magnum loads with cast lead boolits. I have 296 and H110 also. My .44 mold is the Lee 240 gr TL SWC, and I bought the .430 Lee sizing kit...will be here today! I have Recluse lube, LLA, and Rooster Jacket lubes to try. The weather is supposed to crappy this weekend here...so if I can't shoot, I will cast and load!

[beagle]

It's good that you plan to test sevearl powders. I have found that different powders, especially the fast burners like the Dot powders and Unique tend to enhance leading over some of the slower powders. I have not tested many of the new powders so there may be some gems among them as well./beagle

[geargnasher]

ShooterAZ, congratulations on taking the plunge in to casting. I have to warn you though, it's a one-way road to addiction with no cure!

have you fired any commercial cast boolits before, or just those copper J-bullet thingies?

If you don't have much experience shooting lead through your revolver, you might take a look at the "sticky" thread that discusses the topic of revolver accuracy in our classics/stickies section, there are some good hints about dimensional hickeys that many revolvers have that degrade accuracy and promote leading. If you're used to copper-jacketed bullets, there are a few things you should know about cast that you need to consider that aren't much of a factor with the other kind of projectile. Copper doesn't gas-cut, needs to be slighly smaller than groove dimension and cylinder throats to work right, and doesn't have to have any special attention paid to too much case tension. Cast boolits generally need to be just a shade larger than groove dimension, and just under, at, or over cylinder throat dimension (opinions and results vary), and you might want to pay particular attention to any squeezing that the case does on the boolit when you seat it, some brass is tough enough and some boolits soft enough that they can be easily swaged down smaller than you sized them, and this can cause leading. Just seat and crimp a dummy, pull the boolit, and measure it to make sure your expander is expanding the brass enough for the oversize lead boolit.

Hope this helps some,

Gear

[1Shirt]

Have never had leading from a cast blt that is oversize for bore blt, ( that chambers) in either rifle or hand gun, providing I had adequate and appropriate lube. As to vol and leading, have become somewhat a believer in Richard Lee's theory regarding hardness and vol, again providing an oversize (bore riding) blt with appropriate lube. Recommend the Lee reloading manual #2, and if you are going to rifle vols, or for that matter even for hi vol hand gun, a good hardness tester like a Cabin Tree. Good luck.
1Shirt!:coffeecom

[ShooterAZ]

have you fired any commercial cast boolits before, or just those copper J-bullet thingies?
Gear

Yes, I have loaded & fired many, many thousand commercial cast bullets, but mainly only in .45ACP & .38 Special...low velocity. I have never tried loading anything high velocity (beyond 1000 fps) yet...hence all the questions. And yes casting is becoming an addiction...:-D

[Shiloh]

Proper sizing and good lube is what prevents leading.

I've run some near max loads in .357 without leading. Boolit fit is king!!

Shiloh

[fredj338]

AS alreadynoted, velocity is rarely if ever the leading culprit. It's fit then alloy then lube & powder tpe are tied IMO. I've run AC WW alloy to 1700fps in my 45-70 w/ no leading.

[cbrick]

Yep, diddo, I run my 308, 30-30, 7-08 etc with air cooled WW to 2,000 fps without leading. Fit first but another thing I usually do is use the slowest powder that will get me to my velocity goal. If the powder is too slow to reach the velocity try a slightly faster powder till you get there with good accuracy.

Rick

[Iron Mike Golf]

From all I have read by experienced guys here, coupled with some mechanical engineering studies from decades ago, we use hardness and velocity as proxies for alloy strength and chamber pressure respectively. We do that because both are easy and inexpensive to measure.

As noted above, the most important factor is boolit fit. Where the boolit is when pressure peaks would be next, IMO. I am not sure what comes next: lube or alloy strength. It probably depends on the amount of pressure you are putting on the boolit.

Put enough pressure behind a boolit and it will deform where the lands are engraving because, for a little while, the boolit is forced down the barrel and doesn't turn fast enough. The lands cut a groove in the boolit wider than the land itself. Now you have several channels gor gas to blow by and I bet it sucks a lot, if not all, the lube away, too.

If your boolit fits well and you use any of many lubes suitlable for high pressure, you can shoot full house 357 and 44 mag loads using air cooled 92-6-2 alloy. I shoot 92-4-4 and use either BAC or Carnauba Red and both lube work great for me with mag loads in both calibers. Same alloy and lubes also work great for me in 44 Spl, 45 Colt, 9mm, and 45 ACP shooting cast.

[sag]

im getting some leading and im not sure if its the powder or the lube.

I know its not the alloy 20BHN is plenty hard.

Im shooting a .451 212-215grain boolit in my .45LC using 5.7 grain of clays.

velocity should not be an issue should be in the 890-900fps area

I also tried other charges but still get lead. the lube is old phelps lube that came with the phelps lubersizer. im getting lead only in the first 1/2" and throut area...

[waksupi]

im getting some leading and im not sure if its the powder or the lube.

I know its not the alloy 20BHN is plenty hard.

Im shooting a .451 212-215grain boolit in my .45LC using 5.7 grain of clays.

velocity should not be an issue should be in the 890-900fps area

I also tried other charges but still get lead. the lube is old phelps lube that came with the phelps lubersizer. im getting lead only in the first 1/2" and throut area...


Right off hand, I would say your bullets are way too hard. The velocity you are shooting, 11 Bn is about where it should be, maybe even softer. Hard is not the way to go, regardless of what you may have heard or read elsewhere.

Don't be fooled by what you "know"! This is the graduate school. :drinks:

[geargnasher]

im getting some leading and im not sure if its the powder or the lube.

I know its not the alloy 20BHN is plenty hard.

Im shooting a .451 212-215grain boolit in my .45LC using 5.7 grain of clays.

velocity should not be an issue should be in the 890-900fps area

I also tried other charges but still get lead. the lube is old phelps lube that came with the phelps lubersizer. im getting lead only in the first 1/2" and throut area...

Super-hard boolits + really fast powder = unbalanced load. If you're loading to SAA pressures, use Unique and 9-13 bhn boolits. If loading to +P pressures, use 296 or similar with boolits that hard.

Gear

[Jkallen83]

im not new to reloading, but new to casting lead bullets. i am getting leading with a crappy homemade lube i made until my order arrives with lee alox.

but i actually used a different faster burning powder and got less leading...so according to the leading, it says my lube sucks, but when i changed powders to a faster burning powder i got less leading...

im still reading and researching this...so if u got different powders give them a try if u know ur lube is good.

[stubshaft]

The faster powders are helping the boolit to obturate better. It is entirely possible to have a boolit that is too hard and have it lead on you.

[MtGun44]

Start with a known good lube like NRA 50-50 or LBT soft blue. I have no idea what Rooster
jacket is, but if it is one of the hard crayola lubes, don't waste your time, they are marginal
and primarily used by commercial casters who's most important goal is not melting in
handling and shipping heat in the summer.

FIT is the most important thing. You want a boolit to be .001 or .002 larger than the groove
diameter. Harder is NOT necessarily better, and often too hard and too small causes leading.

Bill

[waksupi]

im not new to reloading, but new to casting lead bullets. i am getting leading with a crappy homemade lube i made until my order arrives with lee alox.

but i actually used a different faster burning powder and got less leading...so according to the leading, it says my lube sucks, but when i changed powders to a faster burning powder i got less leading...

im still reading and researching this...so if u got different powders give them a try if u know ur lube is good.

That may be telling you that your alloy is too hard. The faster powder may be bumping up the bullet, as it should, closer to the point of origin. Your bullet may also be undersized. For pistol loads, you can use melted crayons, and probably have a good enough lube. Try softer bullets and size them .001 larger, and I bet the leading goes away.

[Jkallen83]

That may be telling you that your alloy is too hard. The faster powder may be bumping up the bullet, as it should, closer to the point of origin. Your bullet may also be undersized. For pistol loads, you can use melted crayons, and probably have a good enough lube. Try softer bullets and size them .001 larger, and I bet the leading goes away.

yeah, my first attempt to cast was with PURE lead. it shrunk down too small and leaded. someone recommended a harder lead. i went to local scrap yard and someone already had some lead in ingots so i bought it....its REALLY hard lead. i want a softer lead, but ive only had my mold for about a week...i am now getting really beautiful casts, and they measure perfect.

i was too soft the first time, this time maybe too hard...but im learning...i was just stating to the OP my experience in my first week of casting.

im pretty sure its my lube and possibly too hard of lead right now...but i was amazed that changing powders affected it also.

[geargnasher]

Reference my post #4 to the OP who's thread has now been hopelessly hijacked (sorry!). Also, here's a copy/paste from a post I made on another recent thread. Much of the same information applies to your issues, although what I said about case swage may or may not apply to your particular situation:

Here's the truth on leading: Leading is caused primarily by explosive powder gas leaking around the sides of the boolit and abrading it (gas cutting, we call it) and the resulting lead dust gets smeared into the barrel. Lead sticks to lead, so if any lead sticks it often snowballs the more you shoot. Lead also rubs off and sticks to COPPER FOULING like crazy, and also snowballs quickly. Did you remove ALL traces of copper jacket fouling from your barrels before shooting cast boolits through them? If you didn't, that alone could be your problem. Since most leading caused by gas-cutting is due to boolits that simply don't fit the gun, the thing to do is figure out where the leaks could be first. Obturation is the term for achieving a leakproof boolit/barrel seal that won't lead unless the barrel is copper fouled or has dimensional problems like rust pits or uneven rifling, restriction, bulges, sharp-edged throats, etc.. First rule of achieving obturation is to make sure that the boolit starts life larger than the groove diameter of the barrel, usually one thousandth or so. The next rule is to make sure that the boolit actually remains an interference fit all the way to the muzzle. One of the biggest offenders in automatic pistol calibers is case swage, the effect of the brass case squeezing an otherwise properly sized boolit down until it's a tad smaller than groove diameter, allowing gas-cutting and severe leading. The way to determine if you have this issue is to pull a seated/crimped boolit and measure it. Don't skip this step, you need to know what size the boolits will actually be when they are fired out of the case, and often they might be smaller than the were just before you seated them. I think this is much of your problem, because your water-quenched boolits didn't lead as badly. Going to a "relatively" harder boolit can work better sometimes through several mechanisms, and it's important to know the differences. For one, harder boolits resist case swage, so sometimes going harder makes them FIT better when fired. Another mechanisme is sometimes being a bit harder helps the boolit resist slight skid in the rifling, which can open up trailing edge leaks just enough to gas cut.

Ultimately the challenge is to balance the load and make sure the boolits fit dynamically from case to muzzle exit. Balancing the load means using about the right powder burn rate and charge to work within the operating range of your particular alloy choice and the temper of that alloy, use a compatible lube and primer. Making sure the dynamic fit is right to achieve obturation is a matter of knowing the groove dimension, making boolits a bit larger than that, and checking to make sure that they are still oversized when they exit the case, a simple matter of measuring.

Gear

[waksupi]

yeah, my first attempt to cast was with PURE lead. it shrunk down too small and leaded. someone recommended a harder lead. i went to local scrap yard and someone already had some lead in ingots so i bought it....its REALLY hard lead. i want a softer lead, but ive only had my mold for about a week...i am now getting really beautiful casts, and they measure perfect.

i was too soft the first time, this time maybe too hard...but im learning...i was just stating to the OP my experience in my first week of casting.

im pretty sure its my lube and possibly too hard of lead right now...but i was amazed that changing powders affected it also.


I really doubt the lube is your problem. You have a hardness and fit problem, not lube.

[Jkallen83]

ShooterAZ...i cant find the article, maybe someone here knows where to find it....but i read an article that breaks down leading....mine was leading ONLY toward the muzzle which represents a lube problem...but it also diagnosed leading in the other parts of the barrel and give possible reasons...

try to look it up. it was a really good article.

[sag]

ok thanks im going to try adding pure lead to soften up the alloy. Is clays a good powder to shoot with in a 45lc if i get the boolit hardnes lowered? or should i just go with a diffrent powder also...

is there any good rule on boolit hardness for gas checked rifles?

[Larry Gibson]

sag

"the lube is old phelps lube that came with the phelps lubersizer"

I would disagree with those who think it may not be the lube. A poor lube can definateyl cause leading at low velocities let alone high velocities. I've shot many a commercial hard cast .451 - .452 bullet in my 45 Colt revolver with .454 throats in the 800 -900 fps range. Invariable there was leading. A simple tuble lube with LLA many times cured the leading but washing the hard wax commercial lube off and relubing with Javelina always meant no leading, all with the same loads.

I've also shot thousands of .429 sized 44 loads in a magnum revolver with .434 throats with no leading what so ever when using a good soft lube. Use comercial cast with the usual hard wax lube and leading occurs.

A plug for a couple of our sponsors; Lazer Cast bullets have a softer wax lube and generally do not lead even though the bullets are very hard, 22 - 24 BHN. I've recently shot several hundred of the Lazer Cast 200 gr FPs sized at .452 with my own loads and a couple hundred PRCC Evil Roy factory 45 Colt loads through the same Uberti SAA with .454 thoats with no leading.

I suggest you try a softer lube like BAC or Javelina with your bullets.

Larry Gibson

[geargnasher]

ShooterAZ...i cant find the article, maybe someone here knows where to find it....but i read an article that breaks down leading....mine was leading ONLY toward the muzzle which represents a lube problem...but it also diagnosed leading in the other parts of the barrel and give possible reasons...

try to look it up. it was a really good article.

I've read it, and totally disagree with any assessment that leading is caused by "running out of lube". Leading is caused by gas abrasion, metal-to-metal abrasion, or both. If you have gas abrasion (usually because the boolit doesn't fit), lube won't keep the debris from sticking. If you have metal-to-metal abrasion, like a rough forcing cone, rusty bore, or really bad bore or rifling job, lube won't prevent lead being scraped off the boolit.

Boolit lube makes an excellent solder flux, so anyone that claims lube prevents lead from sticking to a gun barrel doesn't know what they're talking about or is using a substance in their lube that I've never heard of.

Gear

[Reload3006]

I kind of disagree about the lube "not preventing" leading. I do agree leading is caused by gas abrasion or metal to metal abrasion. Where the lube comes in is it hopefully prevents adhesion.

Put this way all machinist/tool makers know that you don't Need Coolant to machine some metals.. Aluminum being a classic example. But Coolant is used to prevent adhesion of aluminum to the cutting tools. Obviously metal is being abraded off but its not forming deposits on the cutting tool. I believe this is what our lube is hopefully doing. Preventing adhesion. Yep metal is still being abraded but hopefully not deposited.

[geargnasher]

Here's my take on it, but I'm not an expert, only an experimenter and observer, which is of course quite subjective: Lead, especially with a bit of tin to "wet" it, will solder to steel. It solders better with a wax based flux. If lube prevented this action, a light coat of oil on the barrel would be sufficient, but it is not. Most gun barrels in normal slow fire never get hot enough to melt solder, but the surfaces might for an instant be hot enough to solder lead dust. Graphite from powder fouling mixed with lube might be a better inhibitor than lube alone. For S&G's, do what I did one time: Take a piece of high-carbon tool steel and polish it. Heat it with a low-oxygen flame and try to get a speck of boolit metal to stick to it. Then, add a small bit of boolit lube to it and see what happens. Maybe it's a simulation of what can happen in a gun barrel, or maybe not at all the same, I don't know. But it IS interesting what happens. Maybe lead dust is just ironed on like you say with machine tools, pressure makes it stick, like applying gold leaf to wood (maybe a bad example). Whether it heat solders or just gets stuck, I have yet see a lube that will make up for poor boolit fit, except maybe a few iinstances of adding liquid Alox to coat a pre-lubed commercial boolit. But I don't really refer to liquid Alox as a lube, but an obturation-enhancing conformal coating.

My concept of how lube helps prevent leading is that it seals little gaps, like engine oil on piston rings raises compression. Lube makes a dynamic "fluid gasket" as Fryxell puts it which completes and perfects a good seal made by a well-fitting boolit. Since no barrel bore is absolutely perfect, lube flexes and moves as it needs to under pressure to fill small gaps as they come and go while the boolit is traveling down an imperfect bore. If the boolit/barrel fit isn't good enough, no lube will prevent gas-cutting and it will get blown out the muzzle, or if it's really hard, brittle lube, might just stay stuck on the boolit and gas cut along with it. Only gilding metal or bronze/brass etc. is stout enough not to gas-cut without the assistance of lube, paper jacket, or sealing filler wad. We have to formulate lube so that it has the correct flow characteristics AND stop-leak characteristics, which is why we play with it so much. Some lubes are certainly better for different situations than others, and the fouling that lube leaves behind after every shot is an important factor in maintaining accuracy through long strings and changing barrel temperature, and also for dealing with cold-barrel flyers.

Gear

[sag]

I ended up making some "Bens Red" lube and no longer am having any leading issues. It actually seams to leave a nice lube coating in the barrel. This is using .451 and .452 sized boolits with the clays powder. I also used the bens red in my 7.35 carcano with no problems and great accuracy(4-5" groups at 100 with open sites). I would recomend making some bens red to anyone. Its truly good stuff.

thanks to all

SG

[runfiverun]

elmer called it tinning.
he went so far as to talk about the gas cutting,blowing ahead and that's where the leading was coming from.
he might have mentioned something about tin melting at a lower temp than the lead.
it went on to talk about a square lube groove and how lube could help fix [seal] the base.
i recall him also discussing situations where the 20-1 or 10-1 alloy would be a better choice than his 16-1.
it had something to do with fitting the throats and a bunch of other stuff....
but it was kind of weird to read stuff [written in 1957] that i had kinda figured out myself.