Does Lube Seal? The test.

[Bass Ackward]

I gotta tell ya, I always like to eliminate old wives tales and me being the open minded type, this one has baffled me for decades. Then the neighbor kid gave me the way to enlightenment. I gotta warn ya, if you were traumatized when you found out about Santa, then you might not want to keep reading.

This kid is one of those types that is always asking questions. One day I am wiping off my loaded rounds to put in the box and the kids asks, WHY? I just looked at my rag. What a genius! I can save a reloading step! And no more chamber cleaning. The more I thought about it, the stronger this test actually became.

Brass gives lube every advantage that a bullet can not. Especially when we make our slugs hard enough to resist obturation. Cases never move to scratch off lube compared to a bullet. Brass has more soft bearing area exposed to pressure than a bullet that only feels it on a comparatively hard base. I am NOT asking the lube to lubricate, just to seal.

To be fair, I would use a short barreled handgun so that pressure stayed up high enough to obturate the brass well until after the bullet had exited. My Whelen was also used since it is a bottle necked case in a fixed chamber. Surely the bottle necked case would seal beyond question with those pressures. I would clean after every lube.

So for the last two weeks, I tried several different types of lubes with and without lanolin, soft lubes, hard lubes at different pressure levels and quantities far more than you would find in a bore, at different temperatures.

The results were a complete and total failure. Nothing sealed or sealed better than anything else except for dried on (glued in the gun cases) LLA. And my guns, cases, and shooting bench, glasses, hands and face paid the penalty.

Strange, but as the pressure went up, dirt increased. ( ? ) Before this test, common sense would tell you that the higher pressure, the harder the brass would push out, thus requiring less of the lube to seal. Right?

So the bad news is that we still have to wipe cases and clean chambers. Needless to say, I am not happy with lube as a seal.

Was this a good test? Is it even a fair test? Is there another way?

[dla]

Love that test!

I was always told that lube was a bad thing because it increased bolt thrust. But now I can see that it increases the "crud factor" in revolvers.

[runfiverun]

john.
you just proved that lube can blow out of a lube groove like in a throat or an undersized boolit in a bbl.
i have had super soft lubes blow back from a revolver and coat everything.
hands, brass, gun, cylinder, some even got down the bbl.
it did teach me to try softening my lube in a rifle, if it seemed the one i was using didn't quite make it to the end, before giving up on it or making other changes.

[HangFireW8]

Bass,

I love your experiments. Sorry, having trouble visualizing... did you purposefully lube the brass case on the outside? If so, how much, the neck, mid-case, whole thing?

What exactly is the object? Are you trying to avoid gas leaking and dirty cases on low pressure loads?

I have a few issues with the a priori statements:

Cases never move to scratch off lube compared to a bullet.

OK, cases don't move much compared to boolits, but they do move. They move forward under firing pin impetus, then they move (and/or stretch) backwards under pressure.

I am NOT asking the lube to lubricate, just to seal.

You may not be asking, but it may be volunteering!

So the bad news is that we still have to wipe cases and clean chambers. Needless to say, I am not happy with lube as a seal.

A clean, dry chamber is always necessary for safe shooting, excessive bolt thrust, wedged cases, bolt lug setback, jammed-up revolvers, are all consequences of lubed chambers.

Was this a good test? Is it even a fair test? Is there another way?

Please fill me in on exactly what/where you were lubing, I'd love to discuss this more...

-HF

[1bluehorse]

Boy, it sure is discouraging for me to realize just when I think I'm kinda gettin a handle on this cast bullet stuff someone comes up with something that I haven't a clue what they're talking about.

[BOOM BOOM]

HI,
Thanks Bass for doing this.
This one will require a bit more thought ,
before we try drawing conclusions.

[steg]

I know I've read in the manuals to keep them clean to cut down on bolt thrust................steg

[geargnasher]

Bass, sounds like your test turned into more of an excercise of the laws of hydraulics and human endurance rather than testing a seal! It seems apparent that the lube is going to squirt out everywhere under those circumstances, there's not enough to hold it in place. Also, if your boolits had as much clearance to the grooves as your brass cases had to your chamber walls, (several thousanths, for sure), you know all the lube would blow out of the grooves and out the muzzle way before the boolit does, leaving the boolit dry, and allowing lots of wonderful gas cutting and leading.

Imagine taking a pea-sized lump of boolit lube, placing it on an anvil, and smacking it squarely with a sledgehammer. The lube will splatter in all directions, right?

I think conventional, groove-filling lubes do act as a sealing agent, but only on a very, very microscopic level. I think this is an essential function to aid obturation, but the boolit must accomplish 99% or probably more of the actual seal by itself, and any tiny gaps in the dynamic fit that may occur as the boolit makes its way down a less-than-perfect barrel must be within the limits of the lube's resistance to squirt through them. This is where I postulate that balancing viscocity with pressure is key. Too thin for the boolit/barrel/pressure in question, lube blows out any of the inevitable tiny leak points. Too thick, it doesn't flow to the front edge of the groove to seal and those tiny leak points can become big ones as the high-pressure gas jets through them and opens them up, laying down boolit dust ahead of the boolit to be ironed on and cussed by the shooter at cleaning time. How many boolits have you recovered that looked like you never shot them except for the rifling marks? I've recovered quite a few that still had the grooves completely full, even had perfect rifling marks in the lube. That lube was too hard, in my opinion, even though the seal was good enough to prevent gas cutting. Personally, I like the lube to be gone about an inch after muzzle exit so it has no chance to come off in chunks and cause balance/accuracy issues downrange.

I've pondered this quite a bit too, and this is the first test I know of that anyone else has conducted to actually test the potential sealing ability of lube, although I think that it isn't exactly relative to what happens to a lubed boolit being squeezed down a gunbarrel.

Even 5W30 engine oil can seal piston rings in an engine, ever do a cylinder leakdown test and add a teaspoon of oil? It can reduce the leakage by 90% unless the piston rings are broken, and even then it will make a difference for a few minutes. That may be an apples-to-oranges comparison, too, but I think it's a little closer to what happens to a boolit. I can force cold grease through a Zerk fitting that has only a .020" hole in it, but not very fast. That's where viscosity comes into play. When a boolit gets smacked by the powder and booted out of the gun licketey-split the relatively stiff lube doesn't just blast out of the grooves unless there is a huge boolit/barrel clearance (by huge, I mean a thousandth or two initial clearance), and I bet the stiffness vs. time factor has a lot to do with that.

One test I did do last year was with a bolt action .308, trying to figure out why I was getting leading above a certain point with MML on hot days. I switched back to Felix lube (much stiffer at the same ambient temps) and got rid of the leading. I fired a series of these good loads through it, observed the lack of leading and clean bore, and ran a clean dry patch through it to be sure. I made a primitive breech-seating punch with a brass rod and a fired case, and breech seated a sized boolit without lube and fired it with the same charge of powder, it leaded like crazy with one shot and the recovered boolit was bore size, having stripped all the groove-sized portion off. It also went through the trap sideways at 25 yards. I cleaned the barrel and fired a few more known good rounds through it to good effect, patched, and breech seated a sized boolit that had been liberally doused with 30 weight oil. That boolit leaded the barrel almost as badly as the first one, but it had some traces of engraves left on it although it was gas cut to beat all heck. I cleaned and fired a string as previously, breech seated a normally lubed/sized boolit, and no problems. Recovered boolit was devoid of gas cutting and all but trace lube which was in the corner bases of the grooves, bore was in good condition, and the shot was on target just like the normally loaded ammo.

Then I tried MML again, breech seating this time. Not so much leading as before with them seated in the cases, but still some near the muzzle, so I cleaned and backed off the powder charge a bit, re-conditioned the bore and fired a string of MML breech seated boolits with no leading. Upped the powder charge to the Felix-lubed load and breech-seated a string of MML-lubed boolits with no leading. Tried one seated in the case with the reduced powder charge, got some leading in the throat area only this time. The boolits that leaded in each of these last three cases were all devoid of lube, and the boolits from the first and last that leaded both showed gas cutting and had zero traces of lube. Looking back, I wish I'd put paper in front of the muzzle to observe the lube jettison pattern, I've since learned that if the lube is concentrated in the center around the boolit hole it's getting blown out ahead of the boolit, but if it's a larger, doughnut pattern it's ejecting properly from the grooves at muzzle exit. My conclusion? The MML was too thin so seal in the throat on a really hot day, and I got throat leading. It was also too thin to seal the boolit with a heavier charge of powder compared to a different lube. It was enough to handle a slightly reduced charge of powder, but a stiffer (more viscous lube) did fine even seated in the case with more powder. Someday I'll do more tests directly comparing lube jettison patterns to recovered boolits along with observations of resulting bore condition, but digging a single boolit out of 200 lbs of crumb rubber gets old after about the second time.

I don't know if these few shots proved anything, but they were indicators at least in that situation.

Gear

[cavalrymedic]

What in the world are we talking about here? What's getting lubed? What's being sealed. I think that my IQ is slipping away.

[Bass Ackward]

Actually, this was a multifaceted investigation because I normally lose velocity as a clean barrel fouls and I wasn't lately. My cold weather loads were in a state of not performing well in this transition climate. 40-50 degrees causes me the most trouble. I am good above, I am good below.

The title was an emotional attempt to stimulate thought. I just didn't anticipate doing it at 3:46 AM for somebody. You guys can be diehards.

I was investigating chamber fouling's part in the equation AND did I need a harder lube. Or do I need to dry patch the chamber when I am finished.

In some situations velocity went up and in others it declined. In the situations that it went up, the cases miced smaller and not round compared to a clean chamber that was tied to hydraulics, but the chambers were still dirty and dry. A smaller chamber would add to pressure and change load.

The test served nothing to answer a seal question that I thought that in a way, it might. But it did give me incite in to lube flow / waste. Just how persistent is a lube or does the next slug have to carry it all? Can this test give a visual for what a lube can eventually do without a trial?

Lube going everywhere helped me to visualize lube flow under pressure in a fixed bore and in revolver. In a rifle, the lube flow is virtually nil till the bullet exits when compared to a revolver that has lube flowing back toward the gap once the bullet passes and the muzzle exit. Why a short barrel handgun runs out of lube faster than a longer barreled gun.

How a rifle or a fixed breach has a better chance of maintaining some lube in a bore to help the next slug. Why leading is generally started with a wash at the muzzle as a lube is failing. Why a lube is more or less persistent and it wasn't what I always expected. Lube isn't always used, it can be wasted.

Why a revolver bore can be wet (for lack of a better term) with lube and then dry immediately as the next level powder charge is increased or a 10 degree in temperature change takes place. And the leading generally begins in the cone. Why I might .... want to change my handgun lube appraisal with temperature for different purposes. Essentially make the load work with the lube instead of just developing a load until lube fails.

I guess that I lost focus on lube considering it a necessary evil and this was an epiphany that brought me back. Call it another tool. But it brings on more questions for which I don't have answers. What I am most interested in is: can this thought / testing process be used in a way to predict a revolver lube before shooting? Would save me a lot of time and money.

[Bret4207]

Well Bass, as usual, you lost me. Does lube help seal? To an extent, I think yes. Lube in a decent barrel with a fitted boolit should, in theory, help support the boolit. It should help support the groove walls from collapse from pressure as long as the pressure isn't too high or the barrel/boolit interface to large or rough. So in that sense I think the lube contributes to a seal. But it's not a "seal" like a piston ring or O ring on a ram.

[btroj]

Ok Gear, you have made me rethink a situation I have been fighting.
My 1911 leads with a certain bullet and load with carnuba red. I tried Felix lube and MML. No leading with same load. CR leaded with even higher and lower loads, the other two do not.
Could this be a sign that CR is stiff enough that it doesn't get in front of the bullet and this gives the throat leading? The other lubes are softer and may be getting "squished" in front of the bullet which is preventing the throat leading.

This is an aspect of lubes I had not considered before. Very interesting.

Brad

[44man]

Does this means Bass has finally reached the truth that lube does not seal??? OH MY, I have to send him a hat.
Now Bass, please wipe the brass and leave the boolit alone. That is to reduce back pressure with brass that can't grip chamber walls. I don't want recoil plates or bolts slammed from slippery brass.
Now if you take a compression test with an engine, one dry and the next with oil squirted in, the oiled one will raise compression. That only means there is too much wear on the cylinder and rings and the oil is filling gaps. But it is only around 100 PSI. Does anyone think the oil will seal at 40,000 psi?
Funny that the oil in the cylinder only changes the compression a few pounds!
Now look at a hydraulic piston, what seals? The rubber seal of course and if it fails, fluid will pour out. The rubber seal is the boolit base. If lube sealed why do we need seals?

[Larry Gibson]

Bass

You keep huntin' seals them PITA folks gonna be all over you, especially if your huntin' the onew with big brown eyes and white fur.........

Larry Gibson

[deltaenterprizes]

Lube does not seal, that is why it is called lube and not seal!

[geargnasher]

Lube does not seal, that is why it is called lube and not seal!

How and why you can make a totally unsupported statement like that is beyond me.

44man, you are right to a certain extent, and I've proven that oil won't help seal a boolit against gas blowby much at all, but Felix lube will seal and not blow past the boolit under the same set of circumstances. as the oil alone. My evidence was the appearance of severe gas erosion of the oiled boolit after recovery compared to a perfectly engraved and undamaged boolit lubed with Felix lube. Watery lubes fail at higher pressures, both as a lube and as a "sealer". If you don't believe that, use engine oil for boolit lube one time. You will be hard pressed to find a better high-pressure film lubricant than engine oil, but it won't work by itself in a gun.

Why not?

Because lube does more than lube, it has to be stiff enough to contain itself in the grooves, if for no other reason than so it can hang around at the point it needs to be to provide lubrication of the boolit/bore interface without being blown out the muzzle. The only way it can stay in the grooves when thin engine oil won't has to have something to do with plugging up microscopic leaks that the oil alone can't. The stiff lube either plugs the holes or is too thick to all squeeze out before the boolit leaves the muzzle. Just the way I see it, but I'm going to say that's the way it is unless someone can do some tests to prove otherwise.

Gear

[runfiverun]

gear your idea of the paper is one i have been thinking on lately.
i have been considering an open topped tube with a piece of paper lining it so i can change it out.

any ways lube does seal it is a flexible, flowing, gasket [piston ring if you will]
the groove gives displace metal somewhere to go as the rifling is pressed into the boolit, the lube moves out of the way allowing this to happen and seals the edges of the rifling.
it may leave some behind to help the next boolit along.
but if lube was not more than that, every first shot from a clean bbl would leave a lead streak behind.
can you not use lube?
yep, you need a dead smooth bbl to pull it off though.

as part of my last tests i took some lyman 375449 g/c boolits and lubed two of the grooves.
then swaged them up to 430 and run them through my 445 super mag and two 44 leverguns
my browning 92 and win 94 trapper.
with 8.5 grs unique [cause thats what the dillon was set up for] these are two that didn't get the canellure rolled on them yet.
the lube grooves are on the order of .002 deep and hold just a ring of lube, surely not enough to lube all the way down a 22" bbl.
yet no leading in the shallow grooved rifling on any of the three guns.
so was it sealing or was it lubing?

[runfiveslittlegirl]

I was told to put these up for runfiverun

[runfiveslittlegirl]

sorry about the huge pics. the last is kind of blurry but uts the closest i got

[Catshooter]

Bass,

I'm sorry to be so dense, but are you talking about case lube or boolit lube?


Cat