rbernie
Contributing Member
What purpose, other than to make giant blooming clouds of smoke, does lube on a cast lead bullet serve? Presuming that the answer is, 'To prevent leading', how does the lube accomplish that?
Why lube cast lead bullets?
- Thread starter rbernie
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.38 Special
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I'm not sure if it's known beyond a doubt. For a long time it was thought that the lube acted as a gas seal. Most "experts" now believe this is not the case, and that lube actually acts as a film between bullet and bore, just like in an IC engine.
BigCheese
Member
One test is worth a hundred expert opinions. I suggest you load up a a few boxes of ammo with unlubed bullets and fire them through your favorite shooting iron. Let us know if leading is a problem. Could it be that all that smoke at the range is unnecessary?
The question is not HOW lube prevents leading, but IF it does.
The question is not HOW lube prevents leading, but IF it does.
ReloaderFred
Member
It's what it's called, a lubricant. Without it, the lead will be directly deposited on the surface of the bore, due to friction. Each lubed bullet fired leaves a very thin coat of lubricant on the bore surface, and this helps the next bullet move down the bore smoothly.
You can check this by thoroughly cleaning a sizer/lubricator sizing die with solvent and try to push an unlubed bullet through it, without any other traces of lube either in the die or on the bullet. Lead will be deposited, and the bullet will be very difficult to push through the die.
Then clean the die again and push through a sized and lubed bullet, and after that, another unsized, unlubricated bullet. The second "dry" bullet will go through the die much easier and won't leave a deposit of lead on the surface of the die. This can also be done with the simple sizing dies that Lee makes for use with a single stage loading press, but the results will be the same. Without lubricant, the lead shears off and adheres to the steel.
Hope this helps.
Fred
You can check this by thoroughly cleaning a sizer/lubricator sizing die with solvent and try to push an unlubed bullet through it, without any other traces of lube either in the die or on the bullet. Lead will be deposited, and the bullet will be very difficult to push through the die.
Then clean the die again and push through a sized and lubed bullet, and after that, another unsized, unlubricated bullet. The second "dry" bullet will go through the die much easier and won't leave a deposit of lead on the surface of the die. This can also be done with the simple sizing dies that Lee makes for use with a single stage loading press, but the results will be the same. Without lubricant, the lead shears off and adheres to the steel.
Hope this helps.
Fred
armoredman
Member
I like my Lee single stage sizers...simple or not... 
ForneyRider
Member
I posed this question on another site. With the suggestion that I always use lube.
But I wonder if there is a combination of bullet hardness/toughness and load that doesn't require lube.
Until then, I will lube my bullets. Cleaning guns is not as fun as reloading and shooting.
But I wonder if there is a combination of bullet hardness/toughness and load that doesn't require lube.
Until then, I will lube my bullets. Cleaning guns is not as fun as reloading and shooting.
NuJudge
Member
There are lots of opinions, but I subscribe to it being both a sealer and a lube.
Read these:
http://www.leverguns.com/articles/fryxell/lube.htm
http://castboolits.gunloads.com/showthread.php?t=17538
http://www.lasc.us/Brennan_5-0_BulletLubes.htm
Read these:
http://www.leverguns.com/articles/fryxell/lube.htm
http://castboolits.gunloads.com/showthread.php?t=17538
http://www.lasc.us/Brennan_5-0_BulletLubes.htm
zxcvbob
Member
"It's a floor wax AND a dessert topping!"
ForneyRider
Member
I'm loading up some 200gr RN in my 1911 45.
These are 452 sized bullets made of pure wheel weights of unknown hardness. I water quenched them.
Some with lube, some without.
I have about 200 lubed bullets with Lee Lube Alox.
I have to make some more unlubed.
Going to shoot and see.
Did more research. Johnson's Paste Wax, Lee Lube Alox and some "red" lube seem to be the top 3 most recommended. The idea behind lube is that it prevents/reduces leading of the barrel. Some guys make their own with any combinations of the above and beeswax and Murphy Oil soap.
These are 452 sized bullets made of pure wheel weights of unknown hardness. I water quenched them.
Some with lube, some without.
I have about 200 lubed bullets with Lee Lube Alox.
I have to make some more unlubed.
Going to shoot and see.
Did more research. Johnson's Paste Wax, Lee Lube Alox and some "red" lube seem to be the top 3 most recommended. The idea behind lube is that it prevents/reduces leading of the barrel. Some guys make their own with any combinations of the above and beeswax and Murphy Oil soap.
ReloaderFred
Member
I've been through the process of making my own lube with Ams-Lube Grease and bee's Wax. It was a pain in the butt, took a lot of time and work, and didn't work any better than the commercial lubes. I now buy all my lubes and don't mess with experimenting anymore. I've found what works and I stick with it. It saves time, work and aggravation.
Hope this helps.
Fred
Hope this helps.
Fred
Master Blaster
Member
Nah you dont need any lube, all us old guys dont know a thing about reloading.
Load them up with no lube and shoot them. We will be waiting when you start the "How do I clean the lead out of my barrel thread", with sage advice.
Load them up with no lube and shoot them. We will be waiting when you start the "How do I clean the lead out of my barrel thread", with sage advice.
I have shot lead bullets with wax gas check with zero leading. It actually blew the existing leading out of the barrel. (.358 bullets in a .360ish bore - .38 S&W Model 31)
So, I believe it can act as much a seal as a lube, depending on where it is. Same as when using Super Grex to stop leading. It is sealing the back end.
In normal usage, the lube "lubricates" the bore, and the bullet obturates to seal off the back side to stop flame cutting.
Still, if your bullets do not obturate to fill the bore, you will have leading with normally lubed bullets. The back end has to be sealed. It can be accomplished by (assuming your throats are a good match to your bore in a revolver) matching the bullet hardness to the load, or sealing the back side with Super Grex (or whatever is available today), or using wax gas checks. There may be another way I do not know about.
So, I believe it can act as much a seal as a lube, depending on where it is. Same as when using Super Grex to stop leading. It is sealing the back end.
In normal usage, the lube "lubricates" the bore, and the bullet obturates to seal off the back side to stop flame cutting.
Still, if your bullets do not obturate to fill the bore, you will have leading with normally lubed bullets. The back end has to be sealed. It can be accomplished by (assuming your throats are a good match to your bore in a revolver) matching the bullet hardness to the load, or sealing the back side with Super Grex (or whatever is available today), or using wax gas checks. There may be another way I do not know about.
lordgroom
Member
reloaderFred- How do you make your own wax gas check.
ReloaderFred
Member
lordgroom,
I've never made wax gas checks. That was Walkalong. I have experimented with cardboard impregnated with melted bullet lube, though. It worked ok, but sure wasn't worth the effort.
When I made my own lube, it was for use in a sizer-lubricator, and was a royal pain to melt, mix and pour into molds. There are too many inexpensive lubes on the market for me to mess with it.
Hope this helps.
Fred
I've never made wax gas checks. That was Walkalong. I have experimented with cardboard impregnated with melted bullet lube, though. It worked ok, but sure wasn't worth the effort.
When I made my own lube, it was for use in a sizer-lubricator, and was a royal pain to melt, mix and pour into molds. There are too many inexpensive lubes on the market for me to mess with it.
Hope this helps.
Fred
Wax gas checks are easy to do. A pain, but easy enough.
Get the Gulf blocks of wax. Melt some in a wide non stick pan until you have a thin, 1/32 to 1/16" thick, layer. Let it cool. Peel it off. Charge your case, then press the wax over the case mouth. Seat a bullet.
Works great, but time consuming.
Get the Gulf blocks of wax. Melt some in a wide non stick pan until you have a thin, 1/32 to 1/16" thick, layer. Let it cool. Peel it off. Charge your case, then press the wax over the case mouth. Seat a bullet.
Works great, but time consuming.
Although it lubricates the bore, prevention of lead deposits is more important.
In the late 1950's the NRA conducted lab tests on bullet lube and published the results in a series of monographs. Here is the conclusion:
Due to heat and friction, the lubricant melts and forms a surface boundary layer between the bullet and the bore. In the same manner that your automobile tire 'aquaplanes' on a wet roadway without leaving skid marks, deposition of lead is greatly reduced where the boundary layer intervenes. Interestingly, the boundary layer travels forward from the lube groove and actually forms its barrier between the bore and the entire bearing surface of the bullet. Due to the hot gas flow behind the bullet, little or no trace of lubricant is left behind after discharge. The success of the boundary layer is directly related to the viscosity of the lube (measured by its melting point) and the velocity of the bullet. Higher velocities require lubricants with higher melting points.
For those of you with engineering background in lubricants, you will find this conclusion to be very familiar. The formation of an intervening boundary layer is critical for the success of nearly every lubricant. As you know, you must carefully match the lubricant to the environment in order to be successful.
These conclusions may be contrary to some of your beliefs. I won't argue with you, but I'll encourage you to find those monographs in the NRA archives and discover for yourself.
In the late 1950's the NRA conducted lab tests on bullet lube and published the results in a series of monographs. Here is the conclusion:
Due to heat and friction, the lubricant melts and forms a surface boundary layer between the bullet and the bore. In the same manner that your automobile tire 'aquaplanes' on a wet roadway without leaving skid marks, deposition of lead is greatly reduced where the boundary layer intervenes. Interestingly, the boundary layer travels forward from the lube groove and actually forms its barrier between the bore and the entire bearing surface of the bullet. Due to the hot gas flow behind the bullet, little or no trace of lubricant is left behind after discharge. The success of the boundary layer is directly related to the viscosity of the lube (measured by its melting point) and the velocity of the bullet. Higher velocities require lubricants with higher melting points.
For those of you with engineering background in lubricants, you will find this conclusion to be very familiar. The formation of an intervening boundary layer is critical for the success of nearly every lubricant. As you know, you must carefully match the lubricant to the environment in order to be successful.
These conclusions may be contrary to some of your beliefs. I won't argue with you, but I'll encourage you to find those monographs in the NRA archives and discover for yourself.
SASS#23149
Member
We bought some bullets last month ,unlubed,at a great price.The fella,who sounded knowledgable enough,said 'nah,at .38 velocities you won't need to lube them.'
wrong.!!
we shot five of them today,and leading was very evident.Stopped there,no need to test any further.
Going to pick up some Alox tomorrow,tried pan lubing ,what a PITA that was.ugh
wrong.!!
we shot five of them today,and leading was very evident.Stopped there,no need to test any further.
Going to pick up some Alox tomorrow,tried pan lubing ,what a PITA that was.ugh
Remo-99
Member
I use a an UN-LUBED hard cast 250gr HP in my 44mag, but with gaschecks to stop gas cutting of the bullet base. After examination of some the recovered bullets from the backstop, it was evident that there was lead 'bonded' to the edges around the gaschecks of the fired rounds. This would leave me to believe that in the absence of lube, friction between the bare hard-lead bullet surfaces and the barrel surfaces, is leaving a deposit of lead on the barrel surface, which is then deposited onto the gascheck edge and friction surfaces. So I came to the conclusion, yes they are leading the barrel, but each shot is 'self cleaning' via the gascheck. I have never had any troubles with accuracy and never need to scrape/clean lead from my barrel manually. So I still use those loads UN-lubed and gaschecked.
ranger335v
Member
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- Dec 3, 2006
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"But I wonder if there is a combination of bullet hardness/toughness and load that doesn't require lube."
Sorta. It's called a copper jacket. But even that leaves a bit of copper rubbed on the bore, it needs to be cleaned off too.
Sorta. It's called a copper jacket. But even that leaves a bit of copper rubbed on the bore, it needs to be cleaned off too.
762 shooter
Member
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- Apr 26, 2008
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- 95
Master Blaster is right.
Us old guys just use it because we don't have enough sense to question the practice.
Us old guys just use it because we don't have enough sense to question the practice.
scrat
Member
It's what it's called, a lubricant. Without it, the lead will be directly deposited on the surface of the bore, due to friction. Each lubed bullet fired leaves a very thin coat of lubricant on the bore surface, and this helps the next bullet move down the bore smoothly.
Totally correct. I would advise on not following anyones recomendation on shooting cast bullets that are not lubed. Cleaning a leaded barrel is a night mare. I leaded up a revolver once. I put around 40 rounds through it. Though i was not too sure why it initially leaded up so bad. later on i slugged the bore and changed my lube. also changed powders and it was gone. However that barrel took me a long long time to get all the lead out. Its something i would never recomend doing.
Totally correct. I would advise on not following anyones recomendation on shooting cast bullets that are not lubed. Cleaning a leaded barrel is a night mare. I leaded up a revolver once. I put around 40 rounds through it. Though i was not too sure why it initially leaded up so bad. later on i slugged the bore and changed my lube. also changed powders and it was gone. However that barrel took me a long long time to get all the lead out. Its something i would never recomend doing.
eclarsen
Member
This question was asked on another forum with the following answer--
lube does lots of things, but the most important is that it prevents galling...metal bonding to metal--bullet lead bonding to barrel steel.
lube does lots of things, but the most important is that it prevents galling...metal bonding to metal--bullet lead bonding to barrel steel.
rcmodel
Member in memoriam
:banghead:
If it wasn't necessary, we wouldn't have been wasting our time & money doing it since rifling was invented!
rcmodel
If it wasn't necessary, we wouldn't have been wasting our time & money doing it since rifling was invented!
rcmodel
OP
OP
rbernie
Contributing Member
Didn't say it wasn't nececessary - just asked how it accomplished its necessary function.
<sigh>
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