Boolit lube melting as ejected from gun

[michiganflyer]

Ok here is a question:

As a bullet is fired down the barrel, where does the lube come in to play.

The reason I ask, is I did some tumble lube pistol bullets (.32 acp in this case), and then sized them. The lube remains in the lube grove, yet, it no longer is on the side of the bullet.
So as the bullet is fired, does the bullet speed melt the lube in the grove, therefore lubing the barrel?

If you tumble lube the bullets again, now you have lube on the outside of the bullet as well. Does this actually give the bullet a molecule of lube for the bullet to ride on?

Just curious if anyone knows.

Thanks,.....

[noylj]

The why is not clear, otherwise we would know what lube and how to maximize efficiency.
With tumble lubes, I simply cast and tumble lube. Works very well.
Lee recommends lubing after sizing. Some use case lube on the bullet before sizing.
Alox seems to cling tenaciously to the bullet, such that it may act as a "cushion" between the barrel and bullet.
What I recommend is the caster should always try his/her cast bullets as-cast and tumble lube. If that works, why go any further.
If you get leading, analyze where it is in the barrel and find the most likely cause.
As I remember, leading at the beginning of the rifling may be due to a bullet too small or too hard of an alloy.
If the leading is just towards the front half of the barrel, you have used up the effective lube on the bullet.
I used to have a "cheat sheet," but that computer died and the one I have is a Windoze Vista that can't seem to load external HDs. It can see them and it says they are OK, but it won't access them.
Have you take up a cast bullet mold, you need to experiment and report your findings.

[462]

Search the lasc web-site for a Glen Fryxell lube article.

[geargnasher]

We think we understand how conventional, groove-filling waxy-greasy lubricants work, but I'll be danged if anyone can explain how tumble lube really works. I know that in certain cases it can work well since I tumble lube a few particular loads myself, but I couldn't begin to tell you why it works when it works or why it fails when it fails.

Gear

[lwknight]

The tumble lube is just a thang unto itself.
When it works its great. When it don't ,, who knows why.

[fredj338]

The lube can melt, it can blow off, it can stay put, depends on the lube & the application. I have recovered many bullets most of the lube still in the grooves. I think most feel it prevents gas cutting as much as actually doing any lubricating.

[Bret4207]

I don't believe the lube has enough time to "melt". The same old wives tale was told about leading being caused by the alloy melting. There simply isn't enough time for the temp to rise enough to melt. Now it may flow or be forced about, that I can see.

As to why or how this all works...we have theories and opinion and few facts. Some lubes work better than others. Mule Snot is a fair lube thats popular because it's cheap and easy to apply and it works at least up to 1400 fps in many guns if the pressure isn't too great and the boolit fits in the first place.

[singleshot]

I don't believe the lube has enough time to "melt". The same old wives tale was told about leading being caused by the alloy melting. There simply isn't enough time for the temp to rise enough to melt. Now it may flow or be forced about, that I can see.

As to why or how this all works...we have theories and opinion and few facts. Some lubes work better than others. Mule Snot is a fair lube thats popular because it's cheap and easy to apply and it works at least up to 1400 fps in many guns if the pressure isn't too great and the boolit fits in the first place.

So Bret, what do you use for high velocity/high pressure loads?

[44man]

So Bret, what do you use for high velocity/high pressure loads?
Bret is correct of course. What is important is what lube does BEHIND the boolit when subjected to powder fire. Low flash point lubes burn behind the boolit and smoke. This leaves ash in the bore for the next shot. The bore will be dry with no lube and a bunch of junk for the next shot to run over or try to push out.
I can't explain what happens to allow lube to coat a bore with a tight boolit that should just push everything out but it does, so if lube was acting as a gas seal, there would be none left behind.
Granted there is not much but all that is needed is to keep carbon from the powder softer. Don't look for a greasy bore!
The point is that even the few molecules of lube left behind a boolit should not burn. This is where Alox can fail.
I have shot Felix lube to 55,000 psi with no smoke or leading and no loss of accuracy.
Does powder burn temps affect lube performance? Someone else can figure that out! [smilie=1:
The only thing I am sure of is that one lube will work and another fail but it can be the other way too.
Since lube can not be compressed, will forward thrust of a boolit force lube along the boolit's sides? Maybe, but what you never want is gas pushing forward along the boolit.
This might be why the theory of lube gas seal came about. Maybe lube force back overcomes gas forward pressure with balance but exceed it and gas will cut the boolit. A simple powder change is enough.
I know, I sit here and think too much! :kidding:

[Fire_stick]

To answer the original question, I don't think anyone really knows for sure what is going on. However, if you have not done so already, michiganflyer, you may want to read the following article. http://www.lasc.us/FryxellLubeCastBullets.htm
It kind of puts the question into perspective and makes some sense.

But, I have used the "mule snot" (Lee Liquid Alox) with 308 Marlin Express cartridge and a cast ranch dog bullet. Per Hodgdon, the velocity for the particular load is 2200 fps and the pressure 34,300 psi. But reading Glen Fryxell's article above, maybe it should not have worked so well.

It is an interesting subject for friendly debate.

[44man]

I will not agree with the theory that gas enters the lube grooves because you have already gas cut the boolit and sloughed off lead. If gas is entering all the grooves, what are gas checks for? What about a boolit with a lot of GG's? Does that mean gas has reached almost the front of a boolit.
No, Glenn reads other ideas and sits and thinks about it to come up with theories the same as I do. Is he right, am I right?
I leave that up to all of you but some ideas just can't work.
Gas should never, ever pass the boolit base.
Here are two boolits. The left one is perfect and will shoot almost one hole at 50. The right one shows skid but not at the base band so it sealed off the gas. It has done under 1" at 100.
Notice there is no lube left in recovered boolits. It did the job in the bore and left at the muzzle.
If you think I want gas pressure to go alongside my boolits to pressure lube, you should think about it more. :veryconfu

[Bret4207]

So Bret, what do you use for high velocity/high pressure loads?

HAR! First off, define high velocity/pressure! It varies from gun to gun and person to person. Plain of 50/50 alox/beeswax commercial lube has worked fine in some guns up over 2200fps in 30-30, 308, 35 Whelen, 35 Rem using fairly fast powders like 2400 and Red Dot. That would be pretty high pressure for me. Same for the 357 up into the high 1300's. Mule Snot, for me, runs out around 1400 in many guns, but I have a couple very cast friendly 308's and 8mm's that like it fine up over 1800 fps. I've used Lymans old Black Magic and uniformly poor results in rifles like the 32-20 and 7.65 Argie and in the 44 Special. Why? I don't know. It was quite popular at one time. I've used the old RCBS green and it's preformed well, but that was prior to my becoming enlightened about fit, the boolit hardness myth, etc. I haven't played with the high dollar super lubes like Paco sells. That defeats the purpose of casting in the first place IMO.

I don't believe there is a "magic" lube. I think there are many that do an excellent job. Some homemade lubes like Uncle Felixs Elixir are just as good or better than many commercial magic lubes. Same for Johnsons Paste Wax and it's mixtures. Too many guys report good results for it to be a fluke. Since so many do a good job I have a sort of half baked opinion that maybe lube isn't really lube at all, but something else. What exactly I'm not sure, but not a lube as we think of it. If it was really a lube, then why wouldn't hi-temp greases, teflons and stiff oils work better?

I'm also of the opinion that some boolit designs are more prone to retaining some lube after exiting the muzzle than others. I think this changes with speed, pressure and twist. IOW- I think a slow twist rifle shooting a slower powder at moderate speeds will be more likely to be found in the backstop with lube in the grooves than a fast twist rifle shooting at higher speeds with a higher pressure powder using the same lube. And even that theory might change depending on just what the muzzle pressure is. That is, the more blast surrounding the boolit as it exits the muzzle, it would seem more likely the lube would be blown off, if you follow that convoluted idea.

[44man]

True there is no perfect lube and it can be made from all kinds of stuff. I made a good lube with Safflower oil and Speed Green is good.
I don't think slippery is good at all and consider lube flow more important. A sticky, soft lube works better in revolvers and I have never found a boolit with lube in the grooves with a decent lube but I have found commercial hard lubes with half missing from the grooves or chunks gone here and there. Makes nice balance points doesn't it?
Might as well try to cast air pockets! [smilie=l:
I agree LLA works for many as does the 50-50 stuff and I have used a ton of it over the years. However testing for years has shown a lube will have a great affect on accuracy even if it never leads the bore. Is it because one is either too hard, too slippery?
Does Felix work so good for me because of my lubing techniques? I force it into grooves with my fingers and the boolits have lube all over like LLA tumble lubed. I have to wipe bases and peel off excess lube from noses with my thumbnail but I never wipe boolits, only the brass. Pushing through a Lee die just removes the excess and leaves the sides coated with lube. Yes, it mucks my seating dies.
I have to wonder if making boolits too clean is bad! Nice, shiny boolits with lube only in the groove might not be so good and might be why LLA coated boolits work for many but just maybe Felix is better. I still think Alox has too low a flash point. Mixing it with other stuff like wax increases it.
I don't think pressure or velocity has a thing to do with it working or failing but powder heat might.
So why does a boolit that does not squish the grooves to force out lube shoot so good? It is because you do not want to change the boolit shape. All of you have seen the picture I posted of a slumped boolit that had no GG's left even before it entered the barrel. Why waste time lubing it, the lube went out the gap or in a rifle, it was squeezed out in the first few inches. Lube run out near the muzzle might be caused by boolit deformation and GG destruction.
To think you need gas in the grooves so lube works is a joke. I do not believe in the muzzle pressure stuff at all either.
If you want lube to work, use what works and keep the boolit intact to the target. You need your GG's to the muzzle.
So many say to double dip with LLA, it means you are putting more in the grooves, not the outsides. The outside coating is gone quick but the grooves keep feeding unless they are slumped away.
I have no idea how to convince anyone that you do not want to ruin your boolits. Ask yourself what came out the muzzle! [smilie=p: