Had leading trouble and could use some help (my first cast boolits)

[mcooper]

Hello everybody,

I've been at this forum for a while but just started finding time to load some boolits I have cast. I have a smith and wesson model 640 that I am loading .38special plinking loads for.

I'm using a lee 358-158-RF mold, a lee .358 sizer, and used lee alox for lube this time.
I was just shooting my first workup loads (a total of 11 shots) and I only used 3.7 grains of bullseye for my max load. I noticed a few lead streaks in the grooves of the barrel in the first 1/3 of the barrel that is closest to the cylinder. It took me forever to clean it out with a brush, and I'm afraid this is too much leading in my revolver.

I'd like some help trouble shooting...
I was wondering if the .358 sizer is too large of a diameter? I calipered my boolits and got .3585ish when using little force to close the caliper. Should I get a .357 or .356 sizer die?

I only let the alox dry a couple hours before I loaded these boolits. Also I'm willing to try the paste wax/mineral spirits/alox combination if that is better; I also have some beeswax and I hear it can be a good lube.

Do you have any other suggestions? I want to avoid the heavy leading I experienced this past range session.

Thankyou for your advice and have a merry Christmas!

[RobS]

Your boolit diameter is probably not too large as they can size down if they were once they go through the cylinder throats upon firing. The question is are the cylinder throats too small for your groove diameter. Did the boolits you cast and sized go through your cylinder throats? You should slug your barrel and then see if the slug will go through each of the cylinders as a minimum to seeing if your revolver has the makeup conducive to shooting cast.

As to the boolits after casting we need more info. Are these air cooled and what was your alloy. Did you cast them and then load within a few days? If your alox was straight and you didn't give any help with drying time such as with a fan etc. then I don't think they would have dried enough, but doesn't mean they couldn't have.

More info regards to alloy, age of boolits before reloading and having info regarding your gun's cylinder throat to barrel groove diameter will help a great deal.

[mcooper]

Your boolit diameter is probably not too large as they can size down if they were as they go through the cylinder throats upon firing. The question is are the cylinder throats too small for your groove diameter. Did the boolits you casted and sized go through your cylinder throats? You should slug your barrel and then see if they slug will go through each of the cylinders as a minimum.

As to the boolits after casting we need more info. Are these air cooled and what was your alloy. Did you cast them and then load within a few days? If your alox was straight and you didn't give any help with drying time such as with a fan etc. then I don't think they would have dried enough, but doesn't mean they couldn't have.

More info regards to alloy, age of boolits before reloading and having info regarding your gun's cylinder throat to barrel groove diameter will help a great deal.

Sorry, I meant to include my alloy info and forgot. I used clip on wheel weights and air cooled them. I cast them nearly a year ago.

[noylj]

For best accuracy in a revolver, the bullets must be a slip fit in the cylinder throats and at least 0.001" over groove diameter. In an ideal world, you throat diameters will be 0.358" and your groove diameter will be 0.357".
Have you verified that the bullets are a snug fit in the cylinder throats?
Have you slugged the barrel so you know the groove diameter?
In most cases, as I remember, leading at the beginning of the barrel indicates the bullet may be too small or the alloy too hard.
Someone will correct me quickly if I am wrong.

[mcooper]

For best accuracy in a revolver, the bullets must be a slip fit in the cylinder throats and at least 0.001" over groove diameter. In an ideal world, you throat diameters will be 0.358" and your groove diameter will be 0.357".
Have you verified that the bullets are a snug fit in the cylinder throats?
Have you slugged the barrel so you know the groove diameter?
In most cases, as I remember, leading at the beginning of the barrel indicates the bullet may be too small or the alloy too hard.
Someone will correct me quickly if I am wrong.

I have yet to slug anything as I have no soft lead balls... could I cast some soft lead boolits and drive them through?

ETA: The boolits freely slip through the cylinders with no resistance.

[RobS]

I would size them bigger then. In a revolver .001 can stretch to .002 and even .003. If you can put the bullet into the cylinder and it takes just a bit of push to have them exit that is about perfect. You could cast a some bullets and then as soon as they cool (I mean as soon as they cool to handle, maybe even warm) use them to slug with as they will be soft enough for all practical purposes. Also measure the slugs directly after and not a day later as WW alloy as the tendency to grow a bit as they age harden.

I would size them bigger then. In a revolver .001 can stretch to .002 and even .003 over groove diameter and I prefer to fill my cylinder throats for best accuracy. If you can put the boolit into the cylinder and it takes just a bit of push to have them exit that is about perfect IMO. You could cast some boolits and then as soon as they cool (I mean as soon as they cool to handle, maybe even warm) use them to slug with as they will be soft enough for all practical purposes. Also measure the slugs directly after and not a day later as WW alloy as the tendency to grow a bit as they age harden.

Your boolits are probably hard enough since they were cast a year ago to more than likely not swag down in the sized case upon seating, but pulling a one will verify wouldn't hurt.

[mcooper]

Thankyou all for the suggestions, I'll try slugging the barrel this weekend.

So what do you guys think was causing my leading?
Also is there any reason that this revolver may have trouble shooting cast boolits, or shooting them accurately? It will drive nails with jacketed bullets, I didn't accuracy check the cast boolits I made as I was just shooting the 11 workup loads I had.

[runfiverun]

lube again.
two light coats that are dry are better than one globbed on coat.

you definately want oversized.
did you clean all the copper from the bbl?
and sometimes just a powder change will do it.

[mcooper]

lube again.
two light coats that are dry are better than one globbed on coat.

you definately want oversized.
did you clean all the copper from the bbl?
and sometimes just a powder change will do it.


Just to be sure...I want bigger than .358" diameter? what if my barrel slugs at less?
I didn't clean all the copper before I shot the cast boolits from the revolver...but I think I did in removing the lead. I'll also use a copper solvent cleaner this weekend.


I guess I should get a cast boolit reloading guide....any recommendations?:?:

[rbstern]

First of all, reduce the powder load by approximately 0.5 grains. 3.7 grains of Bullseye is a 38 special +P load when shooting that weight of lead boolit. No need to go there (yet).

Clean the barrel as thoroughly as you can so your next test starts as clean as possible. For the next batch of boolits, use a lot more lube. more than you think you need. It'll be smokey, and the revolver will get a bit messy from extra lube. But that's ok because when you find the right amount of lube, the cleanup will be much easier to deal with than scraping lead from the barrel.

If that works, you can start cutting down on the lube in the next batch until you find the sweet spot.

If that doesn't work, then you can start to look more closely at mismatched dimensions between bullets and bore, which is a more complicated issue to solve.

I suggest this approach because you are using one of the easiest-to-get-it-working-right combos...38 special and wheel weight boolits in a quality revolver.

Recommended book: http://www.midwayusa.com/viewproduct/?productnumber=796528

[RobS]

If that doesn't work, then you can start to look more closely at mismatched dimensions between bullets and bore, which is a more complicated issue to solve.


Boolit fit is the most effective way to stop leading. Putting more lube on is only a Band-Aid and accuracy will be harder to find with a boolit that does not fit the gun right. That is proof in the pudding.

What are your boolits as cast diameter? If they are bigger and will chamber try them. You may not need to size them at all, just lube them.

As to if your barrel’s groove diameter being larger than your cylinder throat diameters then you'll have a tougher time getting cast boolits to work in your revolver. You'll have to rely on obturation of a soft bullet to fill the bore. The other option would be to have the cylinder throats reamed .001 over the groove diameter. I however don't believe your revolver is like this as your chamber throats already take a .3585 sized boolit and the barrel would really have to be out of spec. I'm not saying it can't happen though.

[mcooper]

Boolit fit is the most effective way to stop leading. Putting more lube on is only a Band-Aid and accuracy will be harder to find with a boolit that does not fit the gun right. That is proof in the pudding.

What are your boolits as cast diameter? If they are bigger and will chamber try them. You may not need to size them at all, just lube them.

As to if your barrel’s groove diameter being larger than your cylinder throat diameters then you'll have a tougher time getting cast boolits to work in your revolver. You'll have to rely on obturation of a soft bullet to fill the bore. The other option would be to have the cylinder throats reamed .001 over the groove diameter. I however don't believe your revolver is like this as your chamber throats already take a .3585 sized boolit and the barrel would really have to be out of spec. I'm not saying it can't happen though.

The sized boolits literally dropped through my cylinder throats, so I can go bigger and be fine there.

[runfiverun]

yep it's your cylinder throats you wanna fill not the bbl.
if yer leading is way down the bbl either your lube is giving out, or you need to try another [usually softer] alloy.
if yer in +p territory you are working in a narrow window with fast powders.

[RobS]

Good, then try some unsized, as cast. Make sure they are hard enough by the time you load them though. Aging of WW bullets takes about a week and a half to be hard enough for reloading.

[RobS]

runfiverun:

The leading is in the first 1/3rd of the barrel as stated in the original post.

[RobS]

mcopper: Which S&W 640 do you have; the 357 or the 38 special?

[EDK]

Don't forget that you can put some choreboy on a used bore brush and clean the lead out easily. Make sure it is the copper version rather than copper plated steel. I have occasional problems from a bunch of VAQUEROS that get a bit of lead right at the end of the forcing cone...probably due to problems caused when the barrels were installed...see threads on fire lapping.

:cbpour::redneck::Fire:

[mcooper]

mcopper: Which S&W 640 do you have; the 357 or the 38 special?

I forgot that there are .38 640's. I have a 640-1 chambered in .357 magnum. I just wanted to start with .38 loads to cut my teeth on.

[RobS]

Are you using 38 special brass or 357?

[mcooper]

.38 special brass for these loads, but I have .357...just less of it.

[RobS]

I was just wondering as reference to your load data; more pressures with 38 special brass vs your 357 brass in relation to the charge weight of bullseye you are using. Never the less you're only .3 tenths heavy from a 158 grain cast load in the Lyman Reloading book which is a 16,600 pressure load so you're still in under 20,000 CUP's and is very doable with air cooled WW alloy providing the bullet fit is good. Do you know what the as cast diameter is of those slugs you're using?

[rbstern]

I forgot that there are .38 640's. I have a 640-1 chambered in .357 magnum. I just wanted to start with .38 loads to cut my teeth on.

Which is smart.

In the meantime, less powder, more lube.

[mcooper]

I was just wondering as reference to your load data; more pressures with 38 special brass vs your 357 brass in relation to the charge weight of bullseye you are using. Never the less you're only .3 tenths heavy from a 158 grain cast load in the Lyman Reloading book which is a 16,600 pressure load so you're still in under 20,000 CUP's and is very doable with air cooled WW alloy providing the bullet fit is good. Do you know what the as cast diameter is of those slugs you're using?

I'll cast some bullets this weekend and run my calipers over them. I was using .38 special data from the Hornady 7th edition manual, it had a max load of 3.7 grains bullseye, but lists no pressures associated with that max load.

[RobS]

Your load is fine, not a whole lot of worries there as to gun strength. runfiverun does have good advise with using a bit slower powder though. A quick powder such as BE has high energy and creates pressures quickly. This is harder on boolits and especially in revolvers where it has to go from the cylinder then jump cylinder and work into the forcing cone/barrels throat before finally taking its trip down the bore. A slower powder reaches peak pressures later on in the chain say in the barrel and is easier on the boolits launch. Never the less we are talking less than 20,000 cup's.

[RobS]

I'll cast some bullets this weekend and run my calipers over them. I was using .38 special data from the Hornady 7th edition manual, it had a max load of 3.7 grains bullseye, but lists no pressures associated with that max load.

Very good and if you are interested in learning how to speed up the aging process let me know as it can be done in 24 hours with a oven.

[rbstern]

I'll cast some bullets this weekend and run my calipers over them. I was using .38 special data from the Hornady 7th edition manual, it had a max load of 3.7 grains bullseye, but lists no pressures associated with that max load.

Not concerned about you overloading the gun. Moderating the pressure a bit will place less stress on the base of the boolit. Bullseye develops peak pressure very quickly. If you ask 38 special plinkers using Bullseye with typical 148 to 160 grain cast boolits what they use for a charge, you'll generally hear 2.5 to 3.5 grains, with 3.0 grains being the popular load.

My cast boolits have seen the insides of eight or nine different S&W 38 and 357 revolvers. I've never had to go to a larger size boolit to solve leading in a S&W. I have had leading problems in some of those revolvers that were solved by changes in lube or pressure levels. Lee Liquid Alox can be a tricky issue for a new caster, and my own experience, and what I've seen and read from others, is that we tend to spread the lube too thin, probably because of the way Lee makes the stuff seem magically effective in their instructions.

You may well have a boolit size issue. You've got several easy variables to manipulate. You'll figure it out.

[Bret4207]

If I understand correctly, you're shooing a max load with an undersized boolit. That's a recipe for leading, which BTW removes easily with 4/0 steel wool on an worn bore brush and some solvent. I'd try the boolits unsized, cut my charge back to the 3.0 BE level and see if I could get an inexpensive micrometer because your typical dial calipers aren't real good for measuring stuff like this.

[357shooter]

You could just try lubing some unsized bullets and see how they work. When you get done measuring everything that's all you'll do anyway. Just a thought.

[steg]

try them unsized, within reason, I was getting good results shooting boolits at my bore size, .358, and my mold was dropping at .360, so it was a what the heck try it out, the difference was amazing accuracy went way up, and the leading was just about eliminated. the only problem, if its a problem is that you can see the outline of the loaded boolit, in the casing by the oversize boolit expanding the case when the boolit is seated, it seems only cosmetic to me, but I'm wondering if it will shorten case life or not?................................steg

[243winxb]

3.7 grains of bullseye with a 158gr in 38spec is to HOT. I would also guess your finished bullet is not 158gr,but more heavy. You need a harder alloy, lube again after sizing. The .358 diameter is OK.

[RobS]

NO the diameter is NOT OK as it not optimal for the best possible scenario and especially for accuracy. I'm not saying that it can't be done with an undersized boolit, but why would a person want to go there knowingly to only have to return to boolit fit, a very simple principle to shooting cast in revolvers.

Boolits that are snug in the cylinder throats are going to provide the best possible outcome for accuracy and more times than not is a contributing factor to correcting leading. All mold makers suggest that a person slugs their cylinder throats so they can cut a mold to those specs or larger so the boolit is the correct cylinder throat diameter. Gas cutting can happen just as easily coming from the cylinder throats that are sloppy/too big. Also when the boolits fill the cylinder throats there is a better chance that the boolit will not slump or misalign slightly off center during its flight from the cylinder throats to the bore. More lube as a fix is not going to provide the best results and is not the greatest advice either, period.

Boolit fit, Boolit fit, Boolit fit and then load development/lube etc. Get it right from the start, or as best as one can, as a boolit that doesn't lead can still be an inaccurate load that makes the shooter less than happy.

[243winxb]

Boolits that are snug in the cylinder throats are going to provide the best possible outcome for accuracyShooting a hot 38 load in a 357 chamber is the same as having oversized cylinder throats. Load hot in 357mag brass, then you will not have all that "free bore" in the cylinder. :)

[RobS]

243winxb:

yes and no depending on the boolit design's front drive band and another reason why mold makers want to know those dimensions as well so they can make the boolit fit the gun. I personally would use 357 mag brass vs 38 special for such reasons stated on all loads (plinkers to max), but if I were to use 38 special brass and had the chamber gap between the front drive band and the cylinder throats (free bore as you call it) then I would look at seating the boolit further out into the cylinder throats if possible. If not, then I would be looking into finding a different design that could such as the TL designs as a person can crimp on the TL's for plinker rounds. I am stating though, this is probably not a good idea for 357 magnum maximum loads as boolit jump would be likely.

I don't see the point in using a bullet that doesn't meet the dimensions of a gun as a person then is fighting an uphill battle so to speak.

[357shooter]

243winxb:

I personally would use 357 mag brass vs 38 special for such reasons stated on all loads (plinkers to max),

+1. I didn't realize it is a 357, so using the longer brass can help with leading as well as accuracy. Of course using a fatter boolit too.

[mcooper]

RobS, yes I'd love to learn how to speed up the aging process.

Also, if I water drop my boolits I'll get them harder right?

I'll also load up the .357 cases and see how that works. I was hoping to make this load one that I could fire in a couple of other .38's that I have, but I shoot the 640 the most, so I better optimize for it.

[RobS]

post #12

http://castboolits.gunloads.com/showthread.php?p=1047587#post1047587

Your boolits will be harder if you water drop since you are using WW alloy (it has antimony in it) and to what degree depends on the temp of the boolit, the hotter it leaves the mold the harder they will be once quenched. For plinking rounds in the 38 as well as full 357 mag loads many people have success with plain old air cooled WW.

[357shooter]

For accuracy the best results I've had are with softer lead in my 357. Actually almost pure lead. I'm casting lead with 2% and less tin. The groups open up a bit with WW and open up more with water dropped WW and even more with heated treated WW.

I don't shoot many full magnum loads, I just haven't found the magnum powders to be that accurate.

I mention this just to say that going harder may not get the results you are looking for. Not everyone seems to get the same results as me with their 357 though.

The Lee 158 SWC TL at BHN 7-8 crimped into the second groove, 360 diameter in 357 brass is tough to beat for accuracy. At least in my gun. The 158 RF didn't work out so well though. Maybe it will work for you mcooper.

[243winxb]

Lyman - Heat Treatment of Cast Bullets to Harden Them


Quote:
Q: Is there anything I can do to make the bullets harder?
A: Cast bullets can be heat treated to increase their hardness providing your alloy has some antimony present. To heat treat your bullets: Cast your bullets in the normal manner, saving several scrap bullets. Size your bullets but do not lubricate them. Place several scrap bullets on a pan in your oven at 450 degrees and increase the temperature until the bullets start to melt or slump. Be sure to use an accurate oven thermometer and a pan that will not be used again for food. Once the bullets start to melt or slump, back off the temperature about 5 to 10 degrees and slide in your first batch of good bullets. Leave these in the oven for a half hour. Remove the bullets from the oven and plunge them into cool water. Allow them to cool thoroughly. When you are ready to lubricate, install a sizing die .001" larger than the one used to initially size them. This will prevent the sides of the bullets from work-softening from contact with the sizing die. Next apply gas checks if required and lubricate. These are now ready for loading.

[NSP64]

Slugging the barrel is going to be hard since s&w uses 5 land/goove set up. You need to clean the barrel good and pound a slug through , then pound one just into the barrel and pull it back out. Now compare the two slugs. The slug that was pounded through SHOULD NOT be smaller than the one that was pulled back out. If it is , you have a constriction where the barrel was screwed into the frame.
The boolits should be bigger then the cylinder throats, which should be biggger than the barrel.

[Charlie Two Tracks]

When I first started casting (not that long ago), I ran into the same problem of leading. It turned out that it was not just one issue. The boolits that I was casting were not filling out correctly. The bottom bands were rounded and not squared off. The diameter was reading .359 but when I seated the boolits, they were sized down. I pulled a loaded round and measured the boolit. It was not correct and would fall through the cylinder. I had to find out what a good boolit was supposed to look like from my mould,I used an "M" die for case expansion and made sure I wasn't using too much crimp on my .38 round. There was a lot of stuff for me to learn, just to get started. I've got a couple of calibers and loads that work good now (thanks to these guys here) and if I pay attention, I will learn more about this hobby. Have fun. That's what it's about! IMO

[mcooper]

I'll switch from bullseye once I use up the 3/4's of a pound that I have. Any powder recommendations, maybe unique?

[RobS]

Unique is a good all around powder for 38 special to mid 357 loads. I use Herco quite a bit as a substitute to Unique, but it's a bit slower which works out well for better mid house loads in the magnums. Winchester 231/Hodgdon HP38 is also another one well suited for 38 special/mid 357 loads and is easy metering for powder measures. If you are looking for a powder to foot the bill for only low end 357 and 38 plinker then Alliant PROMO is the best deal going at 80 some dollars per 8 lbs. The only thing with PROMO is it only comes in 8lbs containers.

[Bret4207]

Around 5.0 gr Unique with a 150-160 gr boolit in 38 brass is a pretty standard and effective loading.

I'd also like to mention that HARDER alloy isn't going to cure a fit issue. I don't understand why this keeps coming up time after time but HARDER isn't better if the fit is off from the start.

[tuckerdog]

if boolit is too soft for charge/pressure u will get flame cutting = leading
if boolit is too hard u will get leading, sounds odd i know but its true
slug bore
light target loads 1-20 to 1-18 will be about right
heavy +p loads 1-16

[RobS]

if boolit is too hard u will get leading, sounds odd i know but its true


If a plain base boolit is undersized the only hopes for it to not lead is for obturation to happen (where the boolit bumps ups and expands to fill the bore). Having an undersized hard boolit that can't obturate under the working pressures of the load can cause gas cutting. However, if the bullet fit is good, meaning the diameter of the boolit is properly sized for the cylinder throats and bore, a harder boolit can work. Is it necessary???? It depends on the situation. Can a softer air cooled WW bullet work and in particular to this situation? Yes, and is what many people use. Regardless, fit is the most efficient way to make a revolver work at its best ability.

Should a revolver have undersized cylinder throats to barrel groove diameter the only hopes for such a situation is to rely on obturation of softer boolits or possibly use gas check designs. If I happened to own a revolver as such the first thing I would do is ream the cylinder throats over the groove diameter. As it is though mcooper I doubt has a mismatched revolver in regards to cylinder throats to groove diameter and once he slugs is bore he'll be able to verify this.

[fryboy]

i may of missed it but in case i did it would bear repeating , have you pulled a loaded boolit and checked to make sure after sizing/loading that it's not being swaged down by either the case or crimping die ? ie; is it the same size after loading as before ?