Tumble lube and grooves?

[singleshot]

I've tumble lubed all different kinds of cast boolits. Lately, as I tumble lube some boolits, I said to myself "Self, what's the purpose of the grooves? Why not design some type of 'paper patched' boolit for this since more lube will actually adhere to the boolit?" Sometimes I talk to myself while casting....
Anyway, can anybody help me with this dilemma? If you tumble lube, why have lube grooves?

[462]

Well, this is obviously a case one of not getting the right answer, or possibly no answer, when talking to oneself. Often, I've asked myself if there were others similarily afflicted. It's taken a long time to get the affirmation. Thank you, Singleshot.

I don't tumble lube, so can be of absolutely no help.

[singleshot]

Thanks for the response anyway 462. Glad to know there's more out there! Does your response voice use a different voice? :-)

[FLDad]

I do tumble lube some of my boolits, and it took me a long time to realize that I was applying way too much. Switching to 45-45-10 helped some. So I guess maybe finding new ways to add more lube might be moving in the wrong direction. Just enough to prevent leading close to the muzzle seems like the right amount to me, so maybe that should be the litmus test. Those with more experience may take another view.

[Cowboy T]

Why the lube grooves for tumble lubing? I'd imagine it's to reduce the bearing surface and thus friction, kind of like how Barnes does with their new TSX bullets. And it's true that you don't need a lot of tumble lube. A little goes a pretty long way.

[singleshot]

I do tumble lube some of my boolits, and it took me a long time to realize that I was applying way too much. Switching to 45-45-10 helped some. So I guess maybe finding new ways to add more lube might be moving in the wrong direction. Just enough to prevent leading close to the muzzle seems like the right amount to me, so maybe that should be the litmus test. Those with more experience may take another view.

Yes, I definitely agree with you. I didn't explain my thoughts regarding this.:???: I guess that happens when you converse with yourself too much.

I haven't had any leading problems with tumble lubing. I was thinking more along the lines of less complicated designs, higher BC boolits and increased bullet mass for a given length/design.

In fact, I've had such good results with tumble lubing, I was wondering if there's a better way or should I just leave well enough alone?

[singleshot]

Why the lube grooves for tumble lubing? I'd imagine it's to reduce the bearing surface and thus friction, kind of like how Barnes does with their new TSX bullets. And it's true that you don't need a lot of tumble lube. A little goes a pretty long way.

Good thoughts, Cowboy T! That may very well be the final answer. I understand the importance for a Barnes bullet to look to decrease bearing surface due to the relatively hard bullet material, but I wonder how important that is for Pb tossers?

[HARRYMPOPE]

I have used lee alox on smooth a .310 diameter 135g 30-06 load with good luck at 1200 fps.It was a RN core mold of some kind, just tried it to see if it worked.My guess is it would work with a std bullet shape smooth,but without grooves of some sort most would be scraped off the body during seating.But i have shot many bullets without lube at all at 1200-1600 fps and accuracy is better than most would think,sometimes for up to 100 or better shots.You can shoot under 2MOA in a good 30 or 35 cal this way with a GC bullet sans lube.

Somebody should have Erik Ohlen machine the lube grooves out of one cavity of a mold and do a serious comparison.

HMP

[Gohon]

most would be scraped off the body during seating.

Exactly...........when you seat a bullet that's tumble lubed, the lube is scraped off the sides and rolled into the grooves. So those grooves still serve a purpose even in tumble lubing.

[onondaga]

I tumble lube everything with 45:45:10 and read on this board a member sizing off the TL grooves. That , to me would be the time to select a different bullet mold. I think that even sized almost flat that if there is still a little groove left that helps. The increase in surface area with the shallow grooves helps hold a little extra lube. Completely flat like a paper patch bullet is something I haven't experimented with. I'm not saying it wouldn't work. I always judge my lube by the muzzle and if it isn't there in 5-10 shots and showing a star something is wrong. I haven't had that problem since I began using tumble lube. I like the stuff, I like the method. If a smooth paper patch type bullet carried the lube to the muzzle, I'd keep using it with the bullet.

The plain base bullets for rifle I tumble twice. Gas checked/sized bullets I tumble once before check/sizing and twice after. 100% satisfaction. I do think undersized bullets will lead to lube failure with tumble lube as the lube will be blown past the bullet by gas jetting. I avoid that by slugging bores and good bullet fit.

Maybe my alloys help. I don't know for sure. But I only use 2 alloys and both are with Wheelweight and Linotype mixes and BHN for them is 14 and 20 as cast. The harder alloy with gas checks and tumble lube I have taken to 2700 fps in .223 Rem. without leading. Accuracy was below average at 2 MOA at that speed but the bore stayed clean. 2550 fps peaked accuracy at 1 MOA with that bullet in a single shot heavy barrel NEF Ultra Rifle with 1:12 twist.

My tumble lube doesn't get shaved off seating bullets due to my using good practice of "M" expander dies or or size correct expander bells in sizing dies and then using an universal case mouth flair die. I also optimize avoiding that problem by using the Frankford Arsenal case mouth prep kit with caliber specific brushes and powdered mica to clean polish and dry lube inside case mouths.


Gary

[462]

"Does your response voice use a different voice?"

Different voice? It's an untranslatable language.

[HARRYMPOPE]

i often thin lee Alox with mineral spirits and the thin single coat works well up to 2100 in .30 caliber with linotype/ww mix.A clear carnauba wax product used for wood string instrument care was sent to me by a prominent benchrest gunsmith to try and it worked up to 2700 and MOA in 22 caliber.

HMP

[blackthorn]

I tried asking myself questions and didn't get an answer so I thought why not ask an expert? SO--I closed my eyes and concentrated real hard and asked my question of Elmer! I kept my eyes closed and waited---and Elmer said----Go read the stickies and then use the search function on the Cast Boolit Board!!! Have a great day!

[singleshot]

I tried asking myself questions and didn't get an answer so I thought why not ask an expert? SO--I closed my eyes and concentrated real hard and asked my question of Elmer! I kept my eyes closed and waited---and Elmer said----Go read the stickies and then use the search function on the Cast Boolit Board!!! Have a great day!

I'm really glad Elmer is able to keep up with technology, but a little perplexed (but not that surprised) that he didn't throw me a bone.

Any search on this subject results in hundred if not thousands of irrelevant threads and comments to pour through. I think I've done due diligence:

After months of research on the subject, and without experimentation of my own, here's what I've surmised, echoing quotes of other members on this forum:

"A decade or so ago we had a long thread on the how's and why's of lube grooves and their function. In the end there were a couple of good theories, but few facts. I'm afraid much of lube groove design in the "beauty in the eye of the beholder" as anything else. "
- bret4207

"If you're using an inferior lube or trying to keep fouling soft a big honkin load of lube on a bullet might be best. Use a decent lube with smokeless powder and you can get along with just a bit. A fine thread screw is stronger than a coarse thread screw because the minor diameter is larger. Why would you want to weaken a bullet by cutting a deep wide groove?"
- Pat Iffland

At the end of the day, there may not be a "researched and tested" answer, and that's ok. But before I start plunking down experimentation $$$, I want to know if there's any experience or at least what the experts think currently.

Keep in mind, some of the threads on this subject in this and other forums are years if not decades old.

[SkookumJeff]

Good discussion, although I'm confused, I'm hearing lots of voices but not sure as to exactly how many 'people' are talking here? :wink:

Begs the question, is there such a thing as 'too much lube'? I thought I read somewhere that this could happen?

[singleshot]

I'll attempt to draft a response that concisely concludes my current theories. I'm becoming more convinced that boolit lube's primary function is not lubrication. Lead is a very soft substance compared to steel. Lead is a decent lubricant itself. I've shot completely 'unlubed' lead in low pressure situations with no leading evident in the barrel. I've shot copiously lubed lead at higher pressures with leading. Without compiling a book here and now, here are my main theories to date:

1. Pressure is the main obstacle with lead boolits, not heat or lubrication
2. Boolit lube's primary function is sealing gaps created by pressure as it creates fissures in the bullet
3. The consistency of the lube should match the pressure in that it must be viscous enough at a given pressure to flow, but resistant enough to seal the fissures that form

Some other factors to consider:
Jacketed bullets have no lube.
Copper is a very poor lube compared to lead.
Gas checks help curb leading even though gas checks do nothing to lubricate.

Trying to keep this short, so fire away on these theories and factors.

[singleshot]

Ok, just found this on a totally unrelated topic, but I think it adds to the discussion:

"Recluse, I think among boolit lube experimenters there are two schools of thought. One is what most beginners think and the other is what they think after they discover through experimentation that what they thought was wrong.

The first thought is that lube works by keeping lead from sticking to the bore by forming a non-stick barrier, much like Teflon on a skillet. Veral and Dan both seem to still think this, I don't know why. Then, when the magic non-stick stuff fails and lead DOES stick to the bore, we are left wondering why. Then, maybe, eventually, we learn that boolit lube does much more than lubricate, and that lead deposits in a gun barrel get there by means other than abrasion or lack of lubrication. Lube prevents leading by helping to prevent gas-cutting and the resulting particles of lead being blown ahead of the boolit and ironed on the bore as the boolit passes over them. This is easily proven if you take the time to induce gas-cutting, recover boolits, and observe bore condition. Then, once we get boolit fit, alloy and hardness, lube type and viscosity, barrel condition (restrictions, roughness, etc.), and the correct powder, primer, case tension, crimp etc. required for a gentle LAUNCH ironed out and finally cure LEADING, then we find out that our real challenge isn't preventing leading at all, it is ACCURACY. So we hang on to our original theory, we must find the best, slipperiest, be-all end-all whizbang slickum to reduce friction and give is our beloved accuracy, right? But we try it and it doesn't work! We buy every infomercial miracle engine treatment we see, try aircraft lubes, tool and die lubes, EP grease, synthetic formulations and additives of every kind thinking it must be an improvement. Then, once in a while, we load up some of those old boolits we lubed with Lyman Alox back before we knew everything about lube, go to the range, and find it shoots better than anything we were able to concoct. *sigh*. What makes that stuff work? What are it's limits? Why does it have limits and what factors affect that? Again, we find that accuracy is dependent on as many, and often the same, factors as lead fouling, and we start our lube quest anew. Now, we find that lubricity and viscocity are probably the most important factors to accurate function. AMOUNT of lube is also paramount to consistency in rifles, as just the right type and amount is required for consistent, shot-to-shot bore condition without accumulation and the resulting "purge fliers" many of us have experienced. Change one thing slightly, and often lube has to me altered to match the condition. Boolit lube is truly a balancing act, and can be a sort of razor's edge between slickness, stiffness, temperature range, and amount. Much more than a non--stick layer.

Interestingly, and someone here has proven it, most wax/oil based boolit lubes make excellent soldering fluxes, so they certainly don't work by prevention of lead adhesion directly.

Then, a monkey wrench in the lead-free = best accuracy theory. Has the following ever happened to you?: "Wow! I just shot the best group ever with this (insert your experience) gun, but to my horror found it leaded the bore! I went ahead and and continued shooting, getting many more groups just as good, the leading didn't get worse or better, and the gun still shoots like a laser!. Later I cleaned it and it took three boxes of shells to get it shooting straight again, but this contradics everything I thought I new about accuracy, lube, and leading!" So now we start to accept the possiblity that keeping lead fouling to a minimum might not be a requirement to THE most accurate load possible.

This is the short version of the experiences that have brought me to what little understanding that I do have of lube and its function. I learn something every time I go to the range, and add it to my list of observations to be mulled over on rainy days, trying to distill the most important attributes of lube down to just a few things, and dreaming of the perfect subtances that would fill those attributes at any velocity, pressure or temperature. So far, I've tried just about ever commercial concoction out there, and the only thing that meets ALL of my needs is Felix lube, although slight tweaks are necessary to cover the gamut. At least I understand it well enough to know what tweak to make and when.

Now, let's look at bore coatings. I tried using a coat of Bullplate on bone-dry, freshly cleaned and stripped bores, letting it soak overnight and patching out before shooting to give the bore a fighting chance on not leading, what I found is that if the load is good, it does nothing except fling the fouling shot even higher. With undersized boolits nothing I have ever tried for bore coatings or lube will prevent leading from the resulting gas cutting. This leads me to believe that bore coatings won't prevent leading only by the action my making it non-stick, but that there are other factors at work. I aim to discover what they are.

Gear"

[stubshaft]

You are taking one component and asking how or why it will cure all ills. It is like baking a cake and asking why should we add vanilla extract.

There is no easy asnwer because ALL components interact with each other. Yes you can have great accuracy with a boolit that leads. You can also have crappy accuracy with a boolit that leaves the bore shiney and has a SD of 1.

The only TL boolits I own are RD's. I have tumble lubed conventional boolits and have gotten results on either side of the spectrum as well as lubing and sizing TL boolits.

I personally subscribe to Veral's theories because they work for me, and I can understand the interaction of components with them. I have used his components and considered him a friend for over 28 years.

But theories being what they are, every one has one. They develop them by experimenting to see what works in their gun, with their alloy, using their powder and preferred primers.

There is no one answer to what creates the best accuracy for you.

[462]

Singleshot,
I don't have the answer, but here's an article to ponder: http://www.lasc.us/FryxellLubeCastBullets.htm

Gear's comments -- thank you, sir -- will require a second or third reading.

[singleshot]

Singleshot,
I don't have the answer, but here's an article to ponder: http://www.lasc.us/FryxellLubeCastBullets.htm

Gear's comments -- thank you, sir -- will require a second or third reading.

462, thank you for your time and research. I've read fryxell's article on cast bullets along with just about everything else he's written. In fact, this is the precise article that caused me to start experimenting and pondering even though I blindly stumbled into something that worked fine when I first started casting about 4 years ago.

That being said, I think this is an outstanding article and is worth re-reading and bringing up in this thread!

[singleshot]

Roger that, stubshaft. We're on the same page...sort of. I'm familiar with Veral's theories and have no arguement that using his methodology will produce good results.

Do we have to keep cast boolits below 1600 fps? If so, why? We know bullet material plays a factor, but what factor does bullet structure play? Do cast boolits at higher velocities have trouble engaging the rifling? If so, does the presence of lube grooves help or hurt that situation?

I'm certainly not suggesting that independent of all variables, no lube grooves is better than lube grooves. I can't even quantify what all the variables are, and there are many. My question is not "is this the holy grail of cast boolit shooting?" But rather, "can we improve bullet designs for casters, and optimize the other variables?" As you may well know, lube grooves (like bicycle seats) are a holdover from a previous age and technology. In other words, they weren't invented to deal with modern fire arms, with smokeless powder, precise machining, etc. (Much like bicycle seats came directly from horse saddles. In fact, we still call them saddles.)

My question has been "why lube grooves?" (And yes, lube grooves dictate a certain way of dealing with the rest of the variables.) I've not gotten a satisfactory answer anywhere. In fact, many of the attributes of lube grooves seem to be negative, the main ones being a structurally weaker bullet, lower SD, lower BC, increased machining complexity for the molds, decreased contact with rifling (good or bad?) and there may be others.

I guess the bottom line is: I still got questions

[kirb]

It's ok to talk to your self. It is ok to answer; the only problem is if you say huh that might be a problem. Now talking about tumble lube I want to try it again with the 45-45-10, but in small town Idaho can't find any JPW. Next time to Pocatello I will get some. Locally we have a paste wax called Trewax clear paste wax it has some solvents and carnauba in it. Will this work. Sorry to still you thread it’s the other voice still talking from early casting session.

Kirb

[evan price]

I would think a deep lube groove towards the base would encourage obturation- the base would push forward, collapsing the narrow neck in the middle of the lube groove, forcing the lube outwards towards the surface of the bore. This would seal the bore and lubricate. Probably the Keith style deep, square grooves would be better in this application I would think, but I'm no ballistician.

Anyone got any thoughts on this?

[stubshaft]

Roger that, stubshaft. We're on the same page...sort of. I'm familiar with Veral's theories and have no arguement that using his methodology will produce good results.

Do we have to keep cast boolits below 1600 fps? Cast bullets can be pushed in excess of 3000fpsIf so, why? We know bullet material plays a factor, but what factor does bullet structure play? By bullet structure are you referring to the alloy? or the general characteristics? Do cast boolits at higher velocities have trouble engaging the rifling? The ability of a bullet to be engraved by the rifling is dependent on the strength of the alloy in relation to its ability to maintain an elastic state. Long heavy bullets usually show a wider groove on the front band because the alloy must overcome inertia in order to spin. If so, does the presence of lube grooves help or hurt that situation?It would be dependent on the alloy used and the width/depth of the groove.

I'm certainly not suggesting that independent of all variables, no lube grooves is better than lube grooves. I can't even quantify what all the variables are, and there are many. My question is not "is this the holy grail of cast boolit shooting?" But rather, "can we improve bullet designs for casters, and optimize the other variables?" As you may well know, lube grooves (like bicycle seats) are a holdover from a previous age and technology. In other words, they weren't invented to deal with modern fire arms, with smokeless powder, precise machining, etc. (Much like bicycle seats came directly from horse saddles. In fact, we still call them saddles.)I would have to disagree with you there as lead bullets were still in use when smokeless powder was loaded by ammunition manufacturers.

My question has been "why lube grooves?" (And yes, lube grooves dictate a certain way of dealing with the rest of the variables.) I've not gotten a satisfactory answer anywhere. In fact, many of the attributes of lube grooves seem to be negative, the main ones being a structurally weaker bullet, lower SD, lower BC, increased machining complexity for the molds, decreased contact with rifling (good or bad?) and there may be others.In saying that the bullet is structurally weaker are you referring to the bearing surface? Because in the late 70"s when silhouette shooting was on the rise Elgin Gates did extensive tests on cast and jacketed bullets to determine what it would take to bring down a steel target. The upshot of the tests were that cast bullets had a longer dwell time on the targets. As far as grooved bullets being negative. One of Noslers first jacketed bullets were their Zipedo line. They were solid based bullets with grooves resembliing TL grooves in the solid copper base. Another case in point. When Barnes came out with their copper solids they were inaccurate and caused pressure spikes. They (Barnes) redesigned their bullet and grooved it in order to lessen the bearing surface of the bullet. The TSX looks like a copper bullet with lube grooves. WWII naval guns had copper driving bands to limit the bearing surface of the round.

I guess the bottom line is: I still got questions

I don't have all of the answers in fact I probably have as many questions as you do if not more. Ballistics is not an exact science.

[Bret4207]

I would think a deep lube groove towards the base would encourage obturation- the base would push forward, collapsing the narrow neck in the middle of the lube groove, forcing the lube outwards towards the surface of the bore. This would seal the bore and lubricate. Probably the Keith style deep, square grooves would be better in this application I would think, but I'm no ballistician.

Anyone got any thoughts on this?

Okay, this is part of what we went over in that long thread I mentioned in another post. We discussed how lube reacts within the grooves, what we thought was happening on ignition and why we thought things worked as they did. IIRC the upshot was that lube, no matter how soft or hard becomes liquid (for lack of a better term) under the pressure of firing. It will flow to an extent. But it also becomes part of the driving mechanism, that is it contributes to getting the boolit to grip the rifling because the pressure works like it does in hyrdaulics and lube grips the boolit to an extent. It also becomes part of the seal, being in a liquid state it helps fill imperfections in the barrel/boolit juncture as the boolit moves up the barrel. Then there was talk of the radial speed of the boolit rising and forcing the lube outward too. We also discussed the lube groove shape and capacity and what would be best in theory.

Myself, I came away slightly dazed (about normal for me) and even more mystified than when I started. As to what lubes work best, HAR! your guess is as good as mine. I've used plain old 50/50 alox/beeswax up over 2200 fps with great results and never been able to get past 13-1400 at other times. I've used Lymans old "Black Magic" and had it fail terribly at 38 Special speeds. I've had Mule Snot up over 2K with a clean barrel but I've had it fail at 1600 or so far more often than that. I can't find a relationship between boolit shape or design and lube failure in what I've seen. Why does a seemingly well fitted boolit with TL grooves work great at 1500 from a 357 Mag revolver but fail miserably in a 35 Whelen at the same speed with the same great fit using the same lube? Why does a 311316 shot from 32-20 rifle at 1600+ make leetle teensie tiny groups at 100 yards and leave a spotless barrel, and yet when shot from a 30-30 rifle with a shorter barrel at 1200 lead the muzzle area and give open center groups? My answer is to blame it on dynamic fit issues- the boolit fit/size/lube/alloy/load/gun combo lacks something that I can't quite put my finger on. Sometimes I figure out the issue (most often a pressure curve/fit issue IME) and sometimes I just accept what I get and don't worry about that last 1/2 or 3/4" that I know the gun should do. Sometimes you just discover a gun HATES a particular boolit design. Sometimes you figure out it's an alignment issue. Sometimes you get the idea certain designs work better at higher speeds/pressures than other designs, for instance, I "think" Loverin designs work better across the board as speeds rise than say spire points with more traditional lube grooves like the 311414 or 257418.

I do know this much, as a very general rule (I have been burnt too many times to make hard and fast statements) most guns used with commercial lubes and low to mid range loads will give satisfactory results with common alloys. The smaller the boolit diameter and larger the case the harder it seems to be avoid leading with accuracy as speed/pressure rises. The classic examples of the ends of that spectrum would be something like a 30 Carbine or 45/70 and the 6.5 Swede or 257 Roberts or 22-250. You can bring the 30 Carbine or 45/70 up to full power loads relatively simply with little mucking about. Try and take a large cased, smaller diameter boolit up to factory speeds...that's masters or doctorate level work with cast no matter what the lube grooves look like or what space age lube you use. And for darn sure, using a harder alloy isn't the cure all some would have you believe. [smilie=b:Fortunately 35 Bhn lead alloy comes out of a barrel with 4/0 steel wool and a little solvent almost as easily as 15 Bhn alloy.

I'll see if I can locate that old thread. But it may have been on Aimoo or even Shooters.

[Bass Ackward]

People should have to make lube once in their lives. As soon as they do, then some of the old theories would go out the window.

Lube does two things.

A: It cools the bullet. Lube melts WAY before lead. Liquids cool metal. So as long as there is lube on a bullet or the surface, gas cutting is impossible in the short time a bullet is in the bore. Is gas cutting possible? Oh yes, just that you have to have been something terribly wrong to cause total lube loss which also shows you it doesn't seal anything.

B: Lube prevents the ONLY real form of leading which is galling by providing a film that prevents metal to metal contact.

Boom, that's it. There are two theories for lubing. Surface lubes that lube the bullet it's on basically. And lube in the grooves, that leave more lube behind for the next slug. Having a lube groove deeper than the height of the rifling allows lube to flow 360 degrees around the bullet to where it is needed. A surface lube is trapped between two rifling means that you can have plenty on the bottom of the bore but can't get it to the top where it (gravity pulls down and heat rises) will be needed even though plenty of lube may be available elsewhere. So a surface lube tends to fail sooner or have a smaller useful window.

If lube were going to seal, it would not be left behind. Being lighter and liquid long before the slug, it would flow forward under pressure and the slug would remove any trace of it having ever been there. Every shot would be a lube purge. No, the slug seals so that lube can be left in a film behind. And so if you use too hard of a lube and you are sealed already, then it never heats enough so it doesn't flow to the bore at all. Same as no lube. If you aren't sealed, then it melts slower with the idea that it lasts longer or is better in fast shooting situations such as autos.

Lubes work within a pressure and velocity range established by "THAT GUN'S" bore condition which changes with the ONLY REAL enemy of lube, temperature. Cold temps require less and hot more.

If lube sealed, then all lubes would all work the same in all guns as long as that seal was maintained and temperature would not be a factor. Anybody working with cast long enough soon realizes this is a falsehood. For some a lube works to higher velocity with softer slugs than somebody else. That's only because of bore condition or temperature.

Why is this simple out look important? Because if you look at lube in any other way, you will make decisions in choosing a lube or bullet that will be wrong. And you will not understand why it failed when it fails thus making you a prisoner of it. That will run you in circles looking for the perfect lube or ultra hard bullets instead of learning how to adjust to make anything work. This is why some people have trouble with surface lubes.

It will also have you theorizing about lube groove shapes and changing bullet (molds) designs and on and on.. When lube is sealed, it has hydraulic properties meaning that it CAN NOT be compressed unless it is used. When it is used, it is gone, and you foul. (gall) Now you will lose seal unless pressure is high enough for hardness to cause the slug to deform and reseal. If lube performed the seal, then seal would be permanently lost.

The strongest part of the bullet is the lube groove unless seal is lost. Lube left in a bore will cause a bullet to size at higher and higher velocities just as a tire will eventually hydroplane at some speed. Hydraulic pressure sizes bullets as bullets increase in speed. So lube is actually a fouling. Then it causes the bullet to be undersized and seal is lost. Air blows past the slug and removes the lube from the bore and you have a purge flier.

The best accuracy is achieved just when lube quantity is sufficient to prevent leading. Bore fouling cause bullets to deform and break seal which is when you really get gas cutting. If lube was a reason for seal, then more would ALWAYS be better.

Understanding lube function at it's basic level is what allows you to take full advantage of what you are using and do things that others have problems with. It allows for either longer, accurate shot strings or higher velocities before fouling puts the bite on you and your combo foul / fails.

Why am I pounding on the seal theory? You are free to believe what you want. but if you do believe in it, you won't understand the why these things happened and correct for it. Lube is a necessary fouling to a point and then it causes bad things to happen. And bore condition establishes how TEMPERATURE, hardness, velocity and pressure govern everything.

[prs]

There are boolits for smokeless propellants and no paper patch that do not have grooves, per se. Consider the swaged Hornady lead boolit that is lubed with some variant of tumble lube or alox/wax combo. That boolit is provided with a cross hatched pattern, like checkering to help hold the lube. If their lube is as effective as tumble lube concoctions we use, then ther checkering is probably over done, but true to the American idology, more is better ;-). At least in 45 Colt revolvers their 454 pill over Unique is a very shootable projectile that gave me no problem with leading. Not sure how such a checkered exterior would cast or drop from a mold. I fear it would be problematic.

EvenPrice said: "I would think a deep lube groove towards the base would encourage obturation- the base would push forward, collapsing the narrow neck in the middle of the lube groove, forcing the lube outwards towards the surface of the bore. This would seal the bore and lubricate. Probably the Keith style deep, square grooves would be better in this application I would think, but I'm no ballistician.

Anyone got any thoughts on this?"

Yes. I designed a black powder cartridge boolit with just that feature as one of the main design theories. The PRE 454-250-RF is currently viewable at Dick Dastardly's Big Lube Bullets site and is the original in that series. The lube canyon is only .707 of the nominal boolit diameter, or .32" in the case of this .454" boolit. I had straight WW alloy in mind when choosing to use the approximante "root mean square" as the inner diameter; but the boolit shoots remarkably well even witn cast with "dead soft" lead. The volume of black powder lube is HUGE in that resulting reservoir and proper black powder lubes do indeed tend to act as liquids or hydrualic fluids as the set back pressures act upon them. In the Marlin lever rifle the lube star seems to be a galaxy unto itself. Now, does it actually compress and liquify the lube in diesel fashion? I dunno, I can't observe that in any way. It will shoot even poor quality ffg black powder for as many shots as you care to fire without losing accuracy, fouling-out or even over-heating the barrel. Using quality real BP such as Swiss, the barrel stays so clean you would think you were using Unique. Now, with common modern design revolver type boolits or even some of the old BP era ones such as 454190, the lube seems to exit the barrel still solid in the grooves and black powder in a rifle barrel will foul-out PDQ (although in a revolver barrel, the 454190 holds-up well IF one uses excellent quality black powder). I also use that same boolit (PRS 454-250-RF) with smokeless propellant and it seems to shoot just as well with Unique or TrailBoss regardless the use of BP type lube or LLA cut with 10% mineral spirits. When I designed that boolit, I was out to get a rounds that could be shoot adinfinitum with out blowing moist breath, moist swabbing, or cleaning at all. That was goal #1. Accuracy and tumblng were not really considered as most Cowboy Action targets are inside of 50 yards, shot off hand really fast, and the targest are relatively HUGE. Well, turns out, I am told by some folks who are talented shooter that it shoots very well and does not tumble (I am a rather good shot for a blind man, but relativity must be consdered).

http://www.biglube.com/BulletMolds.aspx?ItemID=5f0e63f2-27c8-40c9-bfa1-b2e167b680e5

prs

[44man]

People should have to make lube once in their lives. As soon as they do, then some of the old theories would go out the window.

Lube does two things.

A: It cools the bullet. Lube melts WAY before lead. Liquids cool metal. So as long as there is lube on a bullet or the surface, gas cutting is impossible in the short time a bullet is in the bore. Is gas cutting possible? Oh yes, just that you have to have been something terribly wrong to cause total lube loss which also shows you it doesn't seal anything.

B: Lube prevents the ONLY real form of leading which is galling by providing a film that prevents metal to metal contact.

Boom, that's it. There are two theories for lubing. Surface lubes that lube the bullet it's on basically. And lube in the grooves, that leave more lube behind for the next slug. Having a lube groove deeper than the height of the rifling allows lube to flow 360 degrees around the bullet to where it is needed. A surface lube is trapped between two rifling means that you can have plenty on the bottom of the bore but can't get it to the top where it (gravity pulls down and heat rises) will be needed even though plenty of lube may be available elsewhere. So a surface lube tends to fail sooner or have a smaller useful window.

If lube were going to seal, it would not be left behind. Being lighter and liquid long before the slug, it would flow forward under pressure and the slug would remove any trace of it having ever been there. Every shot would be a lube purge. No, the slug seals so that lube can be left in a film behind. And so if you use too hard of a lube and you are sealed already, then it never heats enough so it doesn't flow to the bore at all. Same as no lube. If you aren't sealed, then it melts slower with the idea that it lasts longer or is better in fast shooting situations such as autos.

Lubes work within a pressure and velocity range established by "THAT GUN'S" bore condition which changes with the ONLY REAL enemy of lube, temperature. Cold temps require less and hot more.

If lube sealed, then all lubes would all work the same in all guns as long as that seal was maintained and temperature would not be a factor. Anybody working with cast long enough soon realizes this is a falsehood. For some a lube works to higher velocity with softer slugs than somebody else. That's only because of bore condition or temperature.

Why is this simple out look important? Because if you look at lube in any other way, you will make decisions in choosing a lube or bullet that will be wrong. And you will not understand why it failed when it fails thus making you a prisoner of it. That will run you in circles looking for the perfect lube or ultra hard bullets instead of learning how to adjust to make anything work. This is why some people have trouble with surface lubes.

It will also have you theorizing about lube groove shapes and changing bullet (molds) designs and on and on.. When lube is sealed, it has hydraulic properties meaning that it CAN NOT be compressed unless it is used. When it is used, it is gone, and you foul. (gall) Now you will lose seal unless pressure is high enough for hardness to cause the slug to deform and reseal. If lube performed the seal, then seal would be permanently lost.

The strongest part of the bullet is the lube groove unless seal is lost. Lube left in a bore will cause a bullet to size at higher and higher velocities just as a tire will eventually hydroplane at some speed. Hydraulic pressure sizes bullets as bullets increase in speed. So lube is actually a fouling. Then it causes the bullet to be undersized and seal is lost. Air blows past the slug and removes the lube from the bore and you have a purge flier.

The best accuracy is achieved just when lube quantity is sufficient to prevent leading. Bore fouling cause bullets to deform and break seal which is when you really get gas cutting. If lube was a reason for seal, then more would ALWAYS be better.

Understanding lube function at it's basic level is what allows you to take full advantage of what you are using and do things that others have problems with. It allows for either longer, accurate shot strings or higher velocities before fouling puts the bite on you and your combo foul / fails.

Why am I pounding on the seal theory? You are free to believe what you want. but if you do believe in it, you won't understand the why these things happened and correct for it. Lube is a necessary fouling to a point and then it causes bad things to happen. And bore condition establishes how TEMPERATURE, hardness, velocity and pressure govern everything.
Bass, have you ever read my post on lubes? EVERY SINGLE BOOLIT LUBE is a wonderful flux to tin metal for soldering. Thankfully we do not reach that temp in the bore. What is left? FOULING and ASH.
Ash can scrub off lead from a boolit. Alox can leave ash.
No lube makes a seal, only the boolit seals.
Some powders leave more fouling so the lube must be better to keep it soft and allow the next boolit to remove all fouling so the boolit does not run it over and compress it.
If leading starts with the first boolit, it will continue to build.
The thought of grooves compressing to force out lube is also funny because the most accurate boolits will have no groove distortion and will not lead a bore.
It all comes down to what is left in the bore for the next shot. If it is lead or ash that will not move out in front of the next shot, it is a problem. Nothing should ever be run over with a boolit except a good lube that does not build up between shots. Lube film should be the same from one to 10,000 shots.

[45 2.1]

We discussed how lube reacts within the grooves, what we thought was happening on ignition and why we thought things worked as they did. IIRC the upshot was that lube, no matter how soft or hard becomes liquid (for lack of a better term) under the pressure of firing. It will flow to an extent. But it also becomes part of the driving mechanism, that is it contributes to getting the boolit to grip the rifling because the pressure works like it does in hyrdaulics and lube grips the boolit to an extent. It also becomes part of the seal, being in a liquid state it helps fill imperfections in the barrel/boolit juncture as the boolit moves up the barrel. Then there was talk of the radial speed of the boolit rising and forcing the lube outward too. We also discussed the lube groove shape and capacity and what would be best in theory.

Lots of different lubes out there...Huhhh? Some do and a lot don't. The hard lube used on commercial boolits can be seen with rifling marks matching the bands when dug out of a backstop. Undamaged and full lube grooves suitable to be shot again except for the rifling marks. That lube doesn't do much of anything i'd say.

[Doby45]

I have seen what 45 2.1 is talking about. I have seen lube on shot boolits that looks and acts more like rubber or cured RTV sealant.

[kelbro]

It's ok to talk to your self. It is ok to answer; the only problem is if you say huh that might be a problem. Now talking about tumble lube I want to try it again with the 45-45-10, but in small town Idaho can't find any JPW. Next time to Pocatello I will get some. Locally we have a paste wax called Trewax clear paste wax it has some solvents and carnauba in it. Will this work. Sorry to still you thread it’s the other voice still talking from early casting session.

Kirb

That wax works well in 45/45/10.

[Gohon]

No lube makes a seal, only the boolit seals.


Seems Glen Fryxell doesn't agree with you. http://www.lasc.usFryxellLubeCastBullets.htm


Gas pressure rises much faster than the bullet is accelerated, so therefore as the bullet’s surface is ravaged by the lands and gas leaks past the base band, the lube reservoir becomes pressurized, with the gases entering from the rear and pushing forward. This rapid pressurization forces the lube to flow into the defect channels in the engraved driving band in front of the lube groove, sealing off the gas flow and limiting the damage due to gas cutting. If the cast bullet is appropriately sized, then this controlled injection forms a floating pool of lubricant that follows the bullet down the barrel, lubricating the bullet/barrel interface and sealing the high-pressure gases. Kind of a ballistic stop-leak, if you will.

[Bret4207]

Lots of different lubes out there...Huhhh? Some do and a lot don't. The hard lube used on commercial boolits can be seen with rifling marks matching the bands when g out of a backstop. Undamaged and full lube grooves suitable to be shot again except for the rifling marks. That lube doesn't do much of anything i'd say.

As I said, "liquid" for lack of a better term. It moves, or does to an extent. Or at least that's the theory, that between radial forces, boolit compression, acceleration, etc. it becomes "liquid" enough to move. I'm going from memory here, so cut me some slack.

Maybe those hard, crayon lubes simply don't move enough and that's why we find them ineffective?

[Bass Ackward]

Seems Glen Fryxell doesn't agree with you. http://www.lasc.usFryxellLubeCastBullets.htm



Yea, Glenn used to be here quite frequently and we did go round and round on the "seal" element of lube. And he wrote that piece.

Bad thing about print for a writer is that it is there for ever. Elmer found that out as he changed his mind on many things that he wrote over his lifetime such as there was no use in going over 280 grain bullets in 44 caliber. A couple of decades later, he admitted that he missed the boat on that one.

I think of leading as the engine in my car. When that engine is set up properly, then the only thing I need to do is maintain that mechanical balance. I do this with lubricant's with additives to promote cleanliness and prevent wear. If I run that engine hard / hot, I break that lubricant down and I get wear. When something gets materially WRONG with that engine over time, then I have to worry about sealing ONLY SO I DON"T LOSE the lubricants that perform the work.

Nothing I can put in that engine will ever bring it back as well as rebuilding it to have metal again perform the seal.

99% of leading is still galling from shooting an under lubricated slug as lube is the first thing to go from heat and pressure.

So "the seal" is there to maintain the lube. Not the other way around.

[44man]

I agree with Bass. By the time gas is acting on the lube, it has already gas cut the base and sides of the boolit. If lead can't seal in that case, how can some wax and oil stay in place?
It is like worn piston rings and a smoky engine. We are talking maybe 100# of compression there or way less with a worn engine and up to over 50,000# in some guns.
Gas should never go alongside your boolits.
Maybe boolit lube came from Harry Potter! :drinks:

[prs]

Among other things, Bass noted; " When lube is sealed, it has hydraulic properties meaning that it CAN NOT be compressed unless it is used. When it is used, it is gone, and you foul. (gall) Now you will lose seal unless pressure is high enough for hardness to cause the slug to deform and reseal. If lube performed the seal, then seal would be permanently lost.

Your forgot about the heat in this context. Heat is among the factors that will cause substances to expand. Also, a solid becoming a liquid typically expands, as do most liquids becoming gasseous. In your above scenerio, you are NOT out of lube when SOME lube is used, only when the lube supply is mostly depleated. I agree with your excellent posting in general and particularly how it appleis to modern propellants and skimpy lube grooved boolits that do not allow lube to contact the lands. In my PRS design, there is a huge reservoir of lube with excellent "communication" and with the intent for the lube to be soft as black powder lube tends to be (high moisture content also). Expansion by compression of the boolits. I dunno. Expansion due to heat and liquification and gassification, probably to some extent. Jetting past the base seat into the reservoir might not result in jetting past the upper drive band, but not sure. I can't see these things and it would not be a good place to be to witness directly.

prs

[Gohon]

By the time gas is acting on the lube, it has already gas cut the base and sides of the boolit.

They way I read Fryxell's statement, the above quote is what he was saying. Note where he says "as the bullet’s surface is ravaged by the lands and gas leaks past the base band". I read that as him saying due to improper bullet seal from the beginning, gas has already leaked past the bullet base and up to the lube groove. Then he goes on to say "This rapid pressurization forces the lube to flow into the defect channels in the engraved driving band in front of the lube groove, sealing off the gas flow and limiting the damage due to gas cutting". Here he saying gas cutting has already started for what ever reason, but the pressurizing of the lube can/will limit the damage. I don't see where he is saying lube is what seals the bore but that proper lube can aid other factors in sealing the bore and reduce the cutting that is taking place. With this in mind I don't see how one can make a blanket statement that lube will not aid in reducing leading by gas cutting.

Anyway, the way I read his statement is he is not saying the lube is there to maintain the seal but that if the seal is broken, the the lube will limit the damage. At this time I'm not sure Fryxell is really that far if any off point and the comment "no lube makes a seal" may not be factually correct..

[Bass Ackward]

Your forgot about the heat in this context. Heat is among the factors that will cause substances to expand. prs



OK, I'll bite, what heat?

I have shot bullets with air holes in the base. (good grand kid fodder) These holes fill with lube during the sizing / lube process. When I recover the bullets, the lube is still in the base of the slug when I have sealed. It's gone when I haven't.

So if heat was ALWAYS a problem, the lube would never remain on the base.


Lead melts at 465 degrees and up. Lube melts closer to 200 degrees. Just as when you poor water on a piece of steel, you can only heat that steel so hot until the water boils away.

For lead to gas cut every bit of it has to be blown entirely away or evaporated first as it will cool the bullet surface that is moving away and leaving it behind unless I am missing something. If a single portion of a bullet maintains seal, gas cutting is impossible as the lube test above shows.

So again, you have to fear gas cutting to fight an enemy that doesn't exist in 99% of bore situations today unless guys don't clean when necessary. Gas cutting (for mechanical reasons) in today's bores is not what it once was.

[44man]

You can't limit gas cutting damage and the base must never be cut or skid to open channels for gas. The base is your piston ring and nothing must get past it.
It is OK for some skid at the front bands but it never must get to the base. You need a 100% gas seal there.
Boolits recovered with full lube in grooves proves it does not melt.
Even Felix does not melt but is soft enough to spin out of the grooves when it clears the muzzle.
Have you ever caught a fired case from a gun? It is hot, but not really that hot, just finger hot without harming your skin. Just how hot is a boolit that has not stayed behind to absorb heat?
Forget heat, even a paper wad at the base will not burn.
Gas cutting and leading is a mechanical problem.
Sure, lube can melt with hot gas but that gas should not be there.

[singleshot]

Ok, I couldn't find the info I sought through research so....

I sized down some TL-452-230-FN in my .430 Lee push through sizer. They came out with no lube grooves. I loaded and shot them in my Ruger Super Blackhawk 44mag along with some as-cast TL-430-240's. It was difficult to size the bullets down in my little $25 Lee press, so I only did 2.

I cleaned and inspected the barrel prior to the test, fired the boolits sans lube grooves, cleaned and inspected the barrel and fired the as-cast 44 mag boolits.
LLA was the lube used for both tests. Both bullets were fired over a "full load" of H4227. (This last info was included to show these were not pip-squeek loads.)

Other than higher velocity from the 452's mushed down to 430 (expected from lighter weight) I detected no difference in accuracy or leading. (No leading.)

The range was short, only 15 yards. All rounds were shot into logs of about 18" diameter and exhibited full penetration. (The logs were salt cedars for anyone who cares.)

Yes, it was a very limited "test" but my suspicions, some of them anyway, have been satisfied.

One: yes, you can significantly squish boolits with no ill effects.
Two: lube grooves my not be necessary.

YMMV, as always! :grin:

[kynardsj]

I talk to myself all the time, and answer too. Good thing is I know exactly what I'm talking about without having to explain.

[44man]

Just what does lube do? Why does lead need lube? Maybe it doesn't but what about the **** left in the bore from powder? Can one lube work better with fouling from another powder?
Who the heck knows?
Notice a lube groove is BEHIND the front drive band. That means lead is in contact BEFORE lube.
Tell me lube seals and I will tell you you are out of your mind.
My opinion is that it keeps fouling in a state that it will be shot out ahead of the next shot.
Does lube melt from friction, get real, it is like rubbing two sticks for a thousandths of a second rather then many minutes.
How can anyone say the lube is liquid when the boolit is shot.
Pipe dreams!
Why do boolits with zero distortion shoot more accurate then slumped boolits?
I have proven to myself that one lube works better then another. One lube will "RUN OUT" and lead towards the muzzle but recovered boolits show the grooves are still full. Another lube burns and leaves more fouling that will scrape off lead.
Then the boolit that leads the start of the rifling is not good but skid and gas channels are not considered. Funny the lube did not "SEAL".
Did your lube coat the bore and soften fouling AFTER boolit passage to aid the next shot? Or did it all shoot out with the boolit or did it burn behind the boolit?