Leading problem--Question

[Char-Gar]

Unless cast very soft, bevel base bullet are an abomination. Commercial casters use them because they fall from the molds of the automatic machines without hanging up like a flat base would. Some shooters think they are there to enable easy seating but that is not why they are there.

Imagine if you are a dose of hot gas and hit a bevel base bullet that was too hard to obturate, where would you go? Now throw in a lube that is designed to stay on the bullet rolling around in a box and not to form a seal at the base of the bullet or do anything else of value as the bullet slides down the barrel. The hot gas attacks the side of the bullet blasting off lead that attaches to the barrel metal.

Lots of folks seem to buy and shoot them and after a few they fall into several predictable categories;

1. They join the crowd that says all cast bullets cause leading and go back to jacketed only.
2. They dig the lead out and continue shooting until they have another lead excavation.
3. They come here and ask for help and find out what the problem is.
4. They come here an extol the greatness of bullets we know are worthless..go figure on that one.

[mroliver77]

I am always amazed when Gunwriters use factory cast and they perform flawlessly.

To get through a box of factory cast I have resorted to using grits or cream of wheat as a filler. You must work up a new load but the grits help stop blow by and scrub away any leading you pick up. It is really amazing how well they work!

I have also shot my boolits in a barrel heavily leaded from factory cast and a half dozen of them cleans most of the leading out. So I would shoot however many offenders it took before accuracy fell off. Then fire a few of my boolits to clean bore. Or load every 6th or so round with my cast and keep leading fought off.
Jay

[bobthenailer]

to get the lube off of your bullets try washing them in mineral sprits, a parts washer in a car repair shop woks excellent! i have also melted it off in a toaster oven and put the bullets in boiling water . but the solvent workes best with the least amount of mess.

[popper]

Save yourself some work. I didn't remove the green stuff, just TL with LLA/JPW and the leading went away. Accuracy was good, 1.5"@50, mostly horizontal stringing, which is ME.

[geargnasher]

[snip]

Imagine if you are a dose of hot gas and hit a bevel base bullet that was too hard to obdurate, where would you go? Now throw in a lube that is designed to stay on the bullet rolling around in a box and not to form a seal at the base of the bullet or do anything else of value as the bullet slides down the barrel. The hot gas attacks the side of the bullet blasting off lead that attaches to the barrel metal.

Lots of folks seem to buy and shoot them and after a few they fall into several predictable categories;

1. They join the crowd that says all cast bullets cause leading and go back to jacketed only.
2. They dig the lead out and continue shooting until they have another lead excavation.
3. They come here and ask for help and find out what the problem is.
4. They come here an extol the greatness of bullets we know are worthless..go figure on that one.

Listen to Char-Gar, he knows what he's talking about even if he misspells it The name of the game is OBTURATION, meaning that the boolit creates an effective gas seal with the bore from case to muzzle. Usually (not always, but usually) this is achieved with an oversized boolit made from a slighy springy alloy containing a few percent antimony. When this slightly oversized, springy alloy is swaged into the bore by the gas pressure, it is a tight fit that won't leak under reasonable, and often extreme, pressure situations. This situation won't lead in a decent barrel most of the time.

HOWEVER: Being oversized alone won't always do the trick. Since no bore is perfectly smooth or perfectly uniform (especially land width), a boolit has to be flexible and have a lube of the correct viscocity for the application (peak pressure, length of pressure curve, velocity, barrel length, etc.) in order to maintain the seal through the dimensional dynamics of a typical gun barrel. One member here in particular refers to this as "Dynamic fit", and I think the term is perfect.

Dynamic fit must be achieved from chamber to muzzle or gas leaks will occur, and where you have gas leaks, you will have leading, period.

So the load must be looked at in the larger perspective, and BALANCED to achieve this dynamic fit. If the boolit fits the gun, is launched smoothly, carries the correct lube, is accelerated at the right rate, and exits the muzzle cleanly with little or no lube clinging to it afterward and with as low a muzzle pressure as load development can yield, then accuracy and grouping will take care of themselves.

So what IS a balanced load? To me, it's more or less common sense, not really a formula. With the goal of obturation in mind, the alloy needs to be balanced to the pressure range to which you intend to load. You have to make up your mind in the beginning what you want to achieve with this gun, and base everything else on that when building a load for the task you chose. With ultra-hard boolits and crayon lube, it takes a LOT of pressure, and a LONG pressure curve to keep the pressure above the yield strength of the alloy so the boolit base will keep acting as a bore stopper through the peaks and whoops and restrictions and powder fouling and whatever else it meets on its trip to the muzzle. Lots of pressure means max loads, probably slow powders, maybe magnum primers, but generally things of that nature. If you load a popcorn plinking load of midrange shotgun powder behind "Hardcast" carp with stiff "lube" that has little lubricity but tons of viscocity, the boolit will remain at the smallest dimension it was swaged to in the bore for the rest of the trip. So if it hits a tight spot early, it will leak at that point the rest of the way down and leave lead streaks from the gas cutting. So, experience has shown me that medium-strength boolits (my first choice) such as air-cooled clip-on wheel weights or heat-treated low antimony alloys perform best with medium-burning powders much of the time. They also like a soft, conventional lube about like NRA 50/50 (I prefer a similar viscocity version of Felix lube myself) to match. Softer alloys usually like faster powders, lighter loads, and even softer lube IME. There are exceptions, but this is a general trend I've seen over and over. When you have a balance of static fit, burn rate, peak pressure, alloy strength, lube viscocity, lube lubricity, boolit weight, and rifling twist rate, everything is rosy. If you throw one or more of these variables out of balance, the rest of it goes to pot. Accuracy can suffer, leading can occur, powder fouling can accumulate quickly and degrade accuracy prematurely, lube can accumulate and cause periodic "Purge flyers", etc.

That's what I mean when I say a load must be "balanced", and Universal behind commercial hardcast is a fine recipe for leading, even if the static fit is fine, because the "dynamic" fit, the one that will bit you in the trousers, isn't good enough to prevent gas leaks.

Sometimes you can cheat, adding tumble lube to band-aid the issue, and be happy for a while, but I doubt accuracy and the ability to shoot long strings without cleaning will be as good as they could be. You might get by with melting off the old lube and using a good commercial lube like Carnauba Red, but you'll likely have to get out the 2400 or Lil' Gun and start flirting with Elmer Keith pull-the-trigger-with-a-string loads to make it stop leading. If you're going to do it, you might as well do it right, it isn't any more difficult or expensive.

Gear

[felix]

Excellent, and well said, Ian. ... felix

[Char-Gar]

Folks of my generation can't spell for beans. There was no such thing as phonics where we learned to read. We were taught to "sight read", that is learn by rote memory how to spell each and every word. So if we didn't take the time to commit a new word to memory, then there was a good chance we could not spell it. The result is, we are a generation of lousy spellers. My wife is not any better than I am.

This is a new computor and I am still using Internet Explorer. My old one rolled snake eyes. I have not yet downloaded Mozilla which does a spell check every time you type a word. I will have to do that someday. Until that time, you guys will just have to bear up under the burden.

[Tar Heel]

I'll save everyone a LOT of agony. Read From Ingot To Target: A Cast Bullet Guide for Handgunners.

I am AMAZED at how many times I have read of leading issues and yet very few folks (both newbies & "experts") have read any literature, older and newer, regarding leading. There are some definitive books and articles out there regarding leading, alloys & leading, obturation & leading, and of course bullet hardness and its contribution to leading.

Please go to the LASC Website and either download the .pdf version of the aforementioned document or purchase a hard copy by following the instructions there.

http://www.lasc.us/ArticleIndex.htm

[geargnasher]

Tar Heel, that's a very good resource. Listen to the good folks here also and apply it to what you observe with your own load workups, it's like having a room full of personal trainers! I learned more about what I was doing in the last three years than I did in the previous 16.

It's also amazing to me how much published information, much from long-established sources, is dead wrong.

Gear

[Tar Heel]

Tar Heel, that's a very good resource. Listen to the good folks here also and apply it to what you observe with your own load workups, it's like having a room full of personal trainers! I learned more about what I was doing in the last three years than I did in the previous 16.

It's also amazing to me how much published information, much from long-established sources, is dead wrong.

Gear

Excellent advice. If my previous post seemed abrupt (it did when I came back to it later) I'll expand.

Older casters, like me, may not be as adept a locating published material on the web. My 1983 version of the RCBS Cast Bullet Manual may be the only source of information I am aware of. (It isn't but that's my example and I'm sticking to it).

New casters (younger folks or those older folks new to casting) may not be aware of the resources (published material) which are now available on the World Wide Web (thank God) for us to read. Some of it has been vetted and unlike other material on the web, the reader can usually get a feel for that.

My advice to the new caster experiencing casting problems or leading issues is to certainly seek advice here, but to remember that casting has a modicum of "art" to it and that a quick, instant answer on a web forum can't replace diligent research, study of published material and 30 years of experience.

Regarding your last sentence.....Believe none of what you hear, half of what you see, and some of what you read. You are dead on with that statement and anyone reading this can cite examples of the same. So get casting....read, read and read some more, then go apply it.

[Char-Gar]

Tar Heel... Glen Fryxell's ebook is the best single source I know of about cast bullets and handguns. Glen is a real scientist and approaches everything with a through eye. All of his material is based on experience. There are a number of other of his articles on the same host site and all are worth your time to read.

He is a first rate human being to boot. His co-author Rob Applegate is a very knowledgeable cast bullet shooter, high end gunsmith and used to make the best bullet molds on this planet. He no longer makes molds. Rob is a great guy as well. Put the two together and you having a winning combination.

There are indeed published resources that are dead wrong, but Glen and Rob's ebook is not among that number.

You spotted an excellent resource and is well worth passing it along. Those of us who have been around a while are familiar with it, but there are always new folks coming on board, who can use the information.

Also look into joining the Cast Bullet Association. They also have some good information available. They put out a publication called "The Fouling Shot", which is also a good resource. They have a web site.

This is an excellent site with quite a few very knowledgeable folks here with great experience and knowledge. There is also an equal, if not greater number of folks, who are just repeating what they heard or read somewhere, with no experience to back it up. Often they parrot sources that are dead wrong also. For the new person to this site, it is often difficult to know which is which.

[Tar Heel]

Tar Heel... Glen Fryxell's ebook is the best single source I know of about cast bullets and handguns. Glen is a real scientist and approaches everything with a through eye. All of his material is based on experience. There are a number of other of his articles on the same host site and all are worth your time to read.

Should be on the Top 10 List of "Must Read".

[geargnasher]

I hope he doesn't mind, but I'm going to quote Bwana here once again:

"Being able to separate the wheat from the chaff has always been a valuble skill in all of life's activities."

I would add, " but especially so when making ammunition".

Gear

[Brick85]

I am always amazed when Gunwriters use factory cast and they perform flawlessly.

To get through a box of factory cast I have resorted to using grits or cream of wheat as a filler. You must work up a new load but the grits help stop blow by and scrub away any leading you pick up. It is really amazing how well they work!

I have also shot my boolits in a barrel heavily leaded from factory cast and a half dozen of them cleans most of the leading out. So I would shoot however many offenders it took before accuracy fell off. Then fire a few of my boolits to clean bore. Or load every 6th or so round with my cast and keep leading fought off.
Jay

Does the cream of wheat actually scrub the barrel like an abrasive? I don't picture cream of wheat being terribly abrasive, but at bullet velocities I guess it could be. This wouldn't wear the bore any faster than shooting lead or J-word bullets, right?

How much cream of wheat or grits would you use? Enough to put maybe a 1/16" layer on top of the powder? I'm guessing at least that much, up to however much it'd be to fill the case and prevent it from mixing with the powder. You'd want a slightly compressed load, right? Again, to keep it from mixing over time.

I've got an HK in .40 S&W that was leading with some factory cast I tried, and I'm hoping to use boolits from Missouri Casting Company as an IDPA load, since they're so cheap it makes casting this kind of "blasting" load not worthwhile. But I'm pretty sure they're going to lead the barrel and I don't want to take the time to change the lube and anneal them.

[geargnasher]

COW in that application is a band-aid that functions by creating the obturation (gas seal) that the boolit and lube were, for whatever reason, unable to do properly on their own. Usually the culprit is too light of a load with too hard of a boolit, too fast of a powder, too SMALL of a boolit, and lousy crayon lube. A few people have commented from time to time about adding COW and reworking the load around the filler for some situations with revolvers, not sure there's enough space left in the .40 case to get enough in there to do the same job, but it might help. Shoot some first and see what happens. If the boolit is anywhere near big enough, it should work provided you balance the load (assuming "hardcast"-type boolit alloy of around 16 bhn) with a powder like HS6 or Longshot, and plan on making them peppy. I've had good luck with several .40s using powders like that with harder alloys, but they needed to be pushed pretty hard (1K fps or more with 175-grain boolits) before I got a clean burn and no leading. The hard boolits didn't work well with faster powders and lower velocities in the three guns I was working with when I did the testing, but your milage may vary as they say.

Gear

[FirstBrit]

Does the cream of wheat actually scrub the barrel like an abrasive? I don't picture cream of wheat being terribly abrasive, but at bullet velocities I guess it could be. This wouldn't wear the bore any faster than shooting lead or J-word bullets, right?

How much cream of wheat or grits would you use? Enough to put maybe a 1/16" layer on top of the powder? I'm guessing at least that much, up to however much it'd be to fill the case and prevent it from mixing with the powder. You'd want a slightly compressed load, right? Again, to keep it from mixing over time.

I've got an HK in .40 S&W that was leading with some factory cast I tried, and I'm hoping to use boolits from Missouri Casting Company as an IDPA load, since they're so cheap it makes casting this kind of "blasting" load not worthwhile. But I'm pretty sure they're going to lead the barrel and I don't want to take the time to change the lube and anneal them.

Case fillers have only limited applications in handgun loads in my opinion, although I use them regularly in rifle loads with plain based hard cast bullets.

There are some very important issues which are often neglected or the implications of which are not fully realised.

The major one is never add COW as an after thought to a load which has been giving problems like leading! For the simple reason one should be fully aware of what happens when using fillers in this manner. Basically and simply put the volume of the case or the volume for powder burning will be reduced some times significantly! This can have a dramatic effect on chamber pressure. Anyone with a ballistic programme like QuickLoad can simulate the situation to get a fairly good idea of how dramatic the outcome could be. Fillers should never be used in combination with fast powders, whereby fast is relative and must be taken in context with the caliber in question. Fast für handguns loads would be like Bullseye or Titegroup whereas rifle it would be like Hodgdon H-110 or Alliant 2400.

The next issue is enough filler is used so that the empty space between powder and bullet base is filled completely Better still when the powder and filler are slightly compressed. This way there is hardly any mixing of powder and filler even in transport or on storage. The filler provides a reliable gas seal and gas cutting problems are elminated. The steel qualities of today mean there is hardly any chance of unwanted barrel errosion. Although, there is a theoretical risk if the COW might be contaminated with mineral silicates which might arise from the harvesting processes. Anyone with these concerns can easily switch to a synthetic buffer type like those offered by Ballistic Products Inc.

Just as an example with your 40 S&W. A load of 5.0 gr. Hodgdon Universal behind a 175 gr. bullet with OAL of 1.100" according to QuickLoad would generate approx. 1,000 fps ( 5" barrel) with about 24 k. psi. Case fill would be about 83%. A reasonable load in terms of pressure and velocity. Adding a case filler like COW as an after thought would cause the chamber pressure to jump from 24 to 31 k. psi dangerously near max. permitted pressure! However with just 4,5 gr. of Universal and case filler the chamber pressure would come in at about 28 k. psi while maintaining a similar velocity of about 1,000 fps.

Best regards,

Adrian - Germany.

[Brick85]

I thought you'd want it slower rather than faster to help with leading? Bullets too small going too fast being the problem?

I'd prefer a lighter load, because I'll easily be shooting 2-300 rounds of this per month and I'd rather put less wear on the gun if possible. That's the purpose of a practice load after all, and the "P" in IDPA is "practice".

I've got a 170 gr LSWC with what looks like that crayola lube, claimed to be at a brinell hardness of 18. I figured on a COAL of 1.120, so I might have a little more room for the COW. These bullets are a little shorter than the JHP's I've been using, so that means even more room. And I'd be working up a new load, of course, not just dumping it in after the fact (and I'd weigh how much, to try and keep things consistent).

Maybe I should try Blue Dot intead of 700-x, since it's way further down on the burn chart, even slower than Unique. Perhaps I'm more concerned than I need to be about leading because this gun is supposed to have a polygonal bore.

[fecmech]

Two suggestions:
1. Why not try some of Missouri bullets 180 gr RNFP's for the 38-40? They are sized .401 and BHN of 12. They might be better suited to your "light" loads.
2. If you are going to spend all the additional time and effort to load COW for 300 practice loads a week why not just start casting your own?? A few hours over a weekend or two will supply a lot of trouble free bullets.

[Brick85]

Not hundreds per week, hundreds per month. It just seems like too much trouble to cast all those boolits every month when I can buy them for $20. Adding in COW is just a few minutes compared to a few hours.

Good suggestion on the softer bullets. I'll have to try them on the next round. Still have to see how well these work, maybe they'll be great.

[Brick85]

Well, range report. I couldn't have gotten more lead in the barrel if I'd poured it in with a ladle. Loads were all 170 gr Missouri LSWC as I'd mentioned before, using 4.5, 4.7, and 4.9 gr of 700-x with a COAL of about 1.123 average. I don't trim my cases so it varies by maybe +/-.003. No COW filler.

I was able to get the leading out by shooting a few plated bullets through with a load I'd previously worked up. Five rounds cleared out the lead real well after each group of 4 of my lead bullets.

I'm trying to figure out a load using Blue Dot with a filler of Quaker hominy grits (because they taste better than COW so I don't mind having them around). But I don't have Quickload or any ballistic calculator other than what Wiljen has in the Reloader's Reference.

What I'd like to do is figure this out using some 155 gr "hard-cast" lead bullets I've got floating around, that also leaded the barrel last time I tried them, but not so bad. The Speer Manual says 10.0 grains of Blue Dot should give me 1113 fps with their 155 grain TMJ or JHP at a length of 1.120. I only need it around 1065 fps. That's their starting load, and their max load is 11.0 grains at 1221 fps. Much faster than I need.

Now, can anyone run this through their copy of Quickload? Keeping COAL around 1.120 should be fine. About how much Blue Dot should I use with about how much grits as filler to keep the pressures safe and achieve at least 1065 fps? I'm guessing about 8.5-9gr. I'd feel better knowing that someone's software says I'm not going to blow up my gun, even if the software is wrong!