Now I'm confused

[biscot]

I've been thoroughly indoctrinated here to the concept that a gun should be fed a large boolit (at least .001" over bore diameter) or you get blow-by and leading.
Today, on the phone with someone who's an aftermarket barrel-maker and presumably an authority (many of his barrels are used for cast bullet shooting and he himself has shot multitudes of cast bullets) (name withheld to protect the innocent), I was told that too large a bullet causes leading, that they should be sized .001" under bore diameter so the bullet can obdurate and seal. A soft bullet is also preferable to allow it to seal effectively. Too large a bullet, and the excess lead is stripped off in the throat, resulting in leading.
Bullet diameter and hardness (or lack thereof) are the key factors - powder and lube are less important.
So, since I'm still getting leading in my 9mm Hi Power, I'm not sure if I should try a larger bullet or a smaller one, a harder one or a softer one.
I'm thinking I'll try all combinations and see what works.
:veryconfu

[docone31]

Wow, the High Power is good with cast loads.
What I do,
Since cast can equal or at least duplicate jacketed loads, I size my lead castings to .002 overbore, I water drop on casting, and I make my own lube.
My favourite load is the Lee 124 TC with home made lube. I have yet to get any leading at all with this casting. I use wheel weight, water dropped, then pan lubed and sized .357.
I do not crimp, I use the die to taper the case to the casting. I do not want to shrink down the diameter.
As far as obturation, I am not sure about that. I know BP does obturate. A 9mm?
I count on rifleing to engrave on firing. If the alloy is hard enough, skidding is minimal.
I am not sure there is resistance enough in the bore to obturate the casting. Not with smokeless anyway.
Food for thought.
Home made lube is the way to go for me.
I use Lee Push Thru Sizers also.
Has worked for years.

[bowenrd]

How is a bevel base supposed to seal? Makes no sense to me.

[docone31]

It does, and works well.
The bevel is small. More like a rounded edge.
When I have recovered the fired rounds, the bevel was still there, with no evidence of gas cutting, or skidded lands.
I have not however gotten alox lube castings to do anything at all.
There are very good lube receipes out there.
Water dropping might help, or it might not. That is just my way.

[biscot]

As an aside r.e. my Hi Power leading problems, I've finally managed (I think) to get the last vestiges of copper fouling out of my barrel (it's had several thousand jacketed rounds through it) using Outer's Foul Out III. I had noticed there was roughness in the grooves by the throat that I never could get out, but finally it's gone.
I'm hopeful that the leading (which occurred in the same area) was mostly being caused by that roughness.
I'm anxious for this blizzard we're having to be gone so I can get back out to the range and try again!

[biscot]

docone31,
Can you share your lube recipe?

[docone31]

I had a pistol that ran rough. I used some valve lapping compound, very sparingly, for sure, and fired those through the barrel.
I did hot loads with that as I wanted speed.
Matter of fact, I used the lapping compound as lube on some castings.
Now, a sweet little pistol.
I used very fine compound, hot loads, and checked frequently while lapping.
I had a Smith 586, that had an 8 3/4 barrel. In the middle of the barrel was a spot that was not that good. It would do 125gn jacketed flat nose, ok. But castings, it would be like spreading beanut butter.
That one, I fired some jacketeds to get the lead out, then took some lead. This I smeared Clover on it, and pushed it in and out of the bore. That made a difference. I then loaded 12rds, with valve compound impregnated on it. Fired them through and that was the end of jacketed loads through it. From that point on, lead only.
Aside from having a strange balance point, it got real accurate.
That was all it took.
My lube receipe is 55% Beeswax, 45% Gulf wax. From there I add Marvel Mystery oil, some Castrol Stick Wax.
Very little smoke, lots of lube spray on firing, and it smells good.
Once that bore gets polished, very little sticks to it.

[felix]

Biscot, from your first post.... Yes, the guy told you correct stuff. However, the stuff is not an absolute. Start with the largest boolit that fits in the case such that the case can be chambered with no neck interference AND use the slowest powder for the case capacity and boolit weight. As you bring the boolit diameter down, use a faster powder speed, or add more of the existing powder if possible. The idea is to find the ideal obturation for the total load. ... felix

[1Shirt]

Can't go wrong listening to Felix. Never found what he writes to be wrong or not logical.
1Shirt!:coffeecom

[Piedmont]

Biscot, Try any decent lube that fills the grooves of the bullet (not tumble lube). Use any alloy harder than air cooled wheel weights. Size .358 and load 3.5 grains of Bullseye. I doubt it will lead. This stuff isn't complicated. You can tweak the load a bit later but see what happens with that.

BTW I wouldn't presume a barrel maker is an expert on cast bullets. Why would he be? Is he a life-long caster or something?

[nicholst55]

As an aside r.e. my Hi Power leading problems, I've finally managed (I think) to get the last vestiges of copper fouling out of my barrel (it's had several thousand jacketed rounds through it) using Outer's Foul Out III. I had noticed there was roughness in the grooves by the throat that I never could get out, but finally it's gone.
I'm hopeful that the leading (which occurred in the same area) was mostly being caused by that roughness.
I'm anxious for this blizzard we're having to be gone so I can get back out to the range and try again!

I'll bet that will make a major difference in how the gun handles lead boolits.


Biscot, Try any decent lube that fills the grooves of the bullet (not tumble lube). Use any alloy harder than air cooled wheel weights. Size .358 and load 3.5 grains of Bullseye. I doubt it will lead. This stuff isn't complicated. You can tweak the load a bit later but see what happens with that.

BTW I wouldn't presume a barrel maker is an expert on cast bullets. Why would he be? Is he a life-long caster or something?

Sound advice; with the jacket fouling gone, a boolit that's moderately hard and seals the bore, with a GOOD lube, you shouldn't have any leading. I haven't really tried any LLA yet, but I've read enough about lube failures using it to make me rather skeptical about it.

I know, I know! A lot of people use LLA religiously, and never have a problem with it! And then there's the rest, who do. JMHO.

[Pirate69]

For what it is worth. I fire a 124 grain in my 9mm Beretta. It is sized to 0.358", air cooled and tumble lubed with LLA. The bullet is loaded with 4.0 grains of Unique. The gun functions without and problems and it is not leading. It is a keeper load at this point.

[x101airborne]

Jeese, I just cant get past that puff of smoke. That LLA is not a friend of mine. I am trying another recipe called "pinko commie" lube. It is a hard lube that seems to be working well. I have no experience with the 9mm, but I have had more trouble with LLA than success.

[biscot]

Gotta get me some o' that "pinko commie" lube!

[Bret4207]

FWIW, there are 2 major schools of thought on fitting a cast boolit. #1 is like your barrel maker says- Use an undersized soft boolit and smack it really hard, mangling it into the throat and making it large as the throat will allow and then letting the barrel swage it back down to what ever size the barrel is- or so we hope. #2- Start off with a boolit that fit's the throats, or as near as the brass allows, push it far more gently out of the case, without massive obturation, and into the barrel, avoiding the inconsistent mangling/nose slumping/lube loss of the first school of thought. With theory #1 you are hoping that the boolit is force fit into the barrel. With theory #2 you start with it being much closer to fitting the barrel to begin with. I would also add that while the barrel is the final sizer, the dynamic fit of the boolit produced by the pressure of the powder charge and how it reacts on your alloy/temper will vary widely, just as barrel size vary widely. The harder your alloy the heavier/faster powder charge you'd have to use to get your obturation that would mangle the boolit into shape.

My opinion is that the undersize/obturate theory works, but it's a poor excuse for proper fitting of a boolit to a gun. If you start with a properly sized boolit you don't need super soft or super hard alloys and you can still use faster powders. You just remove another variable by using a well fitted boolit.

[44man]

Good show, Bret! :drinks:

[Bass Ackward]

I'll throw in one more thing about sizing just to give you a view from the other side and to antagonize a little.

Plain base bullet shooters must be highly knowledgeable, cast worry warts. The window of opportunity for these folks opens and closes very quickly. They must worry about things a like hardness, lube quality, powders speeds, seating bullets, and other things that in the end are applicable to " ONE " gun.

And the more pressure a cartridge generates and how fast it generates it, and barrel length causes all the tears.

Throw on a GC and you can size where it works in several guns and load what you have on the shelf. Coarse it does cost. But Kleenex and cleaning materials aren't free either. :grin:

[Bret4207]

True, true, true! The GC makes things SOOOOOOOOOOOOOOOO much easier.

[Trifocals]

There are as many ways to get cast boolits to shoot well as flies on honey. What works well for you may not work at all for someone else. Experimenting with different techniques and methods is what makes the lore of cast boolits challenging, fun and rewarding. If you are the kind of person that tries cast boolits once or twice and does not achieve success and then bad mouths them forever after, I can guarantee they will not become your forte. Casting and shooting cast boolits is a dedicated, ongoing learning experience. The reward of satisfaction comes when you have achieved success in making a particular firearm shoot cast boolits well. Hang in there, don't be afraid to try different ideas. LOL

[44man]

There are as many ways to get cast boolits to shoot well as flies on honey. What works well for you may not work at all for someone else. Experimenting with different techniques and methods is what makes the lore of cast boolits challenging, fun and rewarding. If you are the kind of person that tries cast boolits once or twice and does not achieve success and then bad mouths them forever after, I can guarantee they will not become your forte. Casting and shooting cast boolits is a dedicated, ongoing learning experience. The reward of satisfaction comes when you have achieved success in making a particular firearm shoot cast boolits well. Hang in there, don't be afraid to try different ideas. LOL
Another hand shake is in order! [smilie=s:

[HangFireW8]

Today, on the phone with someone who's an aftermarket barrel-maker and presumably an authority..., I was told that too large a bullet causes leading, that they should be sized .001" under bore diameter so the bullet can obdurate and seal. A soft bullet is also preferable to allow it to seal effectively.


Well, I guess a soft boolit IS preferable, especially if you are counting on gas pressure to bump-up your boolit to bore size. :)



Too large a bullet, and the excess lead is stripped off in the throat, resulting in leading.

Well, yes, too large a boolit can be problematic, depending on how smooth and tapered your bore throat is, and the design of the boolit, size of nose, size of first drive band, etc. If you are counting on swaging to happen, you are counting on your equipment to do a good job.



Bullet diameter and hardness (or lack thereof) are the key factors - powder and lube are less important.

Less important until some threshold has passed, and then they become critically important.

For example, I was getting away with shooting an undersized bullet in 45ACP with one (expensive, brand name) lube in one band, and when I switched to another (expensive, brand name) lube in both bands, suddenly got leading again. The first lube was better at compensating for my other issue, sizing.

Likewise, if you are relying on gas pressure to bump-up your undersized boolit, you are relying on the initial pressure curve a great deal, so powder choice becomes important, more important than a perfect-fit boolit.

If you are relying on a very minimal amount of lube for accuracy sake (usually rifle shooting or some kind of longer range shooting), then quality of lube does become very important, too.



So, since I'm still getting leading in my 9mm Hi Power, I'm not sure if I should try a larger bullet or a smaller one, a harder one or a softer one.
I'm thinking I'll try all combinations and see what works.
:veryconfu

That's right! Try them all. You may find that more than one combination will work. Then you can come here and theorize about why!

-HF

[Bret4207]

That's right! Try them all. You may find that more than one combination will work. Then you can come here and theorize about why!

-HF

And that happens just often enough to really mess with your head!!!:killingpc

[Bass Ackward]

A lot of people worry about size. Casters just generally like to worry. It comes with the badge.

So they slug their throats. (generally just one) (and clean) But they don't interpolate that data. What does that measurement MEAN to THAT gun? Well what it means is that it changes actually. Depends on your powder and lube.

Truth is that after the first shot, you lose better than .001 in diameter off that throat measurement. That stuff is what prevents metal to metal contact. That stuff also sizes that next slug ever so slightly.

So in truth, after the first cylinder full is fired from a clean gun, if you size .001 under your throat for a slip fit, or you size to throat, or .002 over your throat, it don't matter except for pressure. The bullets will be the same size with that size getting smaller as heat toughens that fouling.

Try slugging dirty throats for a change. Especially when the gun quits shooting, the information you get can be really interesting. :grin: Might give you incite why certain designs or lubes or hardness tend to work better for that gun.

[felix]

Excellent! ... felix

[geargnasher]

Bass, our experiences disagree. While I do get some powder fouling in my revolver throats, I don't see the same thing happening in my bottleneck-cased rifles, and I actually have slugged the throats of two of them after being shot quite bit without cleaning. I have no doubt that the powder fouling can accumulate under the right conditions, but I just don't see it in guns with good, balanced loads. Oh, and the Felix lube eliminated the need to clean the bores of my guns except for long periods of storage and is very good at maintaining consistent bore conditions.

Gear

[Bass Ackward]

I was speaking mostly of revolver throats. Straight cases.

Bottle necked cases enhance powder burn even at the same pressure levels so you get less tagamet. Cases are generally longer so the throat is farther away from the heat. What is in the revolver throat builds up inside your case. People say not to use the same cases for jacketed that you use for cast because of head space. But case capacity can also be altered throwing surprise pressure.

You can get a lead / lube donut in the throat too if a rifle is shot enough. And it will harden with time. Sometimes it has to be broken up by a brush to bring you back.

[MakeMineA10mm]

There's lots of right and divergent opinions being expressed here, which is probably confusing, and I think a big part of that is because we're all talking about different things. Some are talking about rifles, some about auto-pistols, and still others about revolvers...

In a rifle, particularly a bottle-neck cartridge, and especially if going for high velocity, it's said that exact diameter of the throat/groove is ideal. (And those numbers may vary, depending on the barrel & chamber, so you makes your choice and youse takes your chances...) I agree with Brett's comments about nose slumpings, etc., when applied to the long, sleek, slender rifle boolits. I'm not sure it's that big of a deal with pistol bullets, depending on the nose design or length of the boolit...

In a revolver, it's well-accepted that you size to throat diameter, regardless of the barrel's groove diameter. Of course, it's always better if your throats are all the same size, and that that size is the same or larger (but not more than a couple thousandths) than the groove diameter. If you're shooting Keith boolits or any other bullet with a drive-band that sticks out of the case into the throat, you'll have to go .001" smaller than throat, or you'll have difficulty seating your loaded rounds when you go to load/reload.

In an auto-pistol, which is what I think you're really asking about, we have several variables. Does your barrel have an abrupt throat? (Many do - in fact I've got a Walther P88 that has no throat at all - at the end of the chamber the dang rifling starts! It's so bad I have to shoot ammo that is loaded only with bullets that have no significant nose diameter outside the case... Of course, that's also the most accurate pistol I've ever shot or ever seen shot. It will fire 25 rounds into 1-1/2" at 25 yards, so I'm not "fixing" the throat!) Does your barrel have polygonal rifling? (Those throats are different sometimes.) There's a lot of variables with auto-pistols, not the least of which is groove diameter, since a lot of them were emergency war-production. My WWII P-38 likes fatter bullets than does my Hi-Power...

The following applies to handguns and straight-walled rifles at low velocities, like light loads in the 444 Marlin or 45-70.

As far as what boolits work, I must confess I've had very good luck with good ol' air-cooled WWs. I've casted tens of thousands of bullets out of this, and unless you're loading them over 1600fps, they won't lead because of the alloy. (Rough bore, prior leading, wrong sizing dia., poor/no lube, etc. and they will, but it's NOT the alloy's fault.) Nowadays I add 2% tin (or so) just to improve their looks, but hardness-wise, they work the same as straight WWs.

Since joining here, I've intended to make Felix lube or buy Lars BAC, but I got 50 sticks of NRA lube already made up from a buddy who quit casting, so I continue to lube everything with it, just as I did before joining here, in fact, from when I first started casting & reloading 30 years ago. It's a great lube, but pretty smokey. If you use Felix', Lars, or NRA-formula lube, you won't get leading because of the lube, again sticking to under 1600fps without a gas check or up to 2000+fps with one.

As far as plain-base boolits, I've shot them made of Air Cooled WW & with NRA-formula lube up to 1600fps, with no leading, great accuracy, and no problems, other than some smoke from the lube. There's no NEED for gas checks at low velocity, except as a crutch for not doing something else right. Size the boolits correctly, use the right lube, make them from the right alloy, and load them right and you don't need GCs. Size them wrong, and GCs will reduce or eliminate the leading that the mistake should produce, but it's not ideal.

I have a half-dozen 44 Magnums, probably 15 9mms, four 38/357s, and 10 45s, and I do not load specialized ammo for each gun. I want my ammo to be safe and functional in all of my guns. As OCD as I am, it would still be too big a hassle to keep them all straight, if I had unique loads for each individual gun in the safe. Not to mention, when I want to shoot THAT gun, all I'll have loaded up on the shelf is ammo for THIS OTHER gun... And, if the factories can make good ammo that meets a certain spec and works in almost every gun out there in that caliber, why can't I??

So, for pistols (which sounds like what you're asking about) I use air-cooled WW and NRA lube and plain-based or bevel-based boolits (for the most part). I load them at or under 1200fps. (My 45s and 38s go about 800fps at the slow end, and my 44s & 357s go 1200fps at the high end. [Although the 44s do reach close to 1600fps in the carbines.]) My 9mm and 10mm loads go about 1150fps, so they're near the high-end. I load all these pistol loads with W231, except the high-velocity magnums, which get AA#9. With the W231, I tend to run near the max-end of loads, while with the AA#9, I tend to run towards the starting-load or mid-load level, not max-end...

For sizing, I've found the following to work for me in all my guns. You may have to adjust, if you have something that is particularly tight or loose:

9mm - .357"
10mm - .401"
38/357 - .359"
44 - .432"
45 - .452"

I've found little to no leading in any of my pistols following these practices. If there's a pistol with a generous bore (like my WWII P38) and I shoot .357" bullets in it (when .358" are more to it's liking), I still find I have little leading, probably because I'm at the max-end of a faster pistol powder, so before the bullet moves any appreciable amount, it's probably slugging-up and obturating. Shoot that same .357" 9mm boolit in my P88 with the tight barrel/throat, and it gets swaged down, but with no area to blow-by the gases, there's still no leading. Obviously, if one sizes to extremes, there will be problems at the opposite end. I wouldn't want to shoot .355" boolits in my WWII P38, nor would .358" boolits even fit in my P88. In the middle, and with the right alloy and load (to ensure obturation), there's no problem at either end or the middle...

Now, another factor which can't be overlooked is bullet design. In the revolver, it's handy to have a boolit that has a front driving band that sticks out of the case and engages the throat. This keeps the cartridge from laying on the bottom of the chamber and some of the bullet getting shaved at the bottom while there's a gap at the top. (And, again, in a revolver, you want to size .001" smaller than throat, so the bullets will slip into the chambers, so there's no issues here whatsoever, as long as all your throats are the same size.)

However, in an auto-pistol, I've found that it's handy to have a bullet that has little to no full-diameter section sticking out of the front of the case. I seat my TC-nosed bullets so the ogive/front driving band junction is just barely visible outside the mouth of the case. On my RN-nosed boolits, I find the same point on them, and seat as close to that point as possible. On SWC-nosed (the only one I have for the auto-pistol is the H&G 68 copy I ran), I try to put just the least little bit of the front driving band peaking out of the case mouth, perhaps .004" or less. This keeps me from having feeding problems and more-importantly, seating in the chamber problems. Nothing worse than having to bang on the back of the slide to get it to go into battery that last .005"-.010"... These techniques allow one to load a bullet with a sized-diameter above the throat diameter without having any functioning problems.

Whew! I gotta get a cold drink and take a break now! :mrgreen:

[MT Gianni]

With the perfect barrel you would have no variation in bore from the throat to the muzzle. In theory starting undersize and slapping it up to bore size would give you a smooth path. In the real world that isn't going to happen. Bullets need to be tough enough to hold onto the rifling changes and small variations in bore diameter without tearing and being disformed. If his bbl are perfect I would like to know which brand they are but until then I'll start mine oversize.