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View Full Version : Bullet lube and accuracy???



Trifocals
05-18-2009, 06:31 AM
Nope, this is not about whether or not different lubes have an effect on accuracy of a cast bullet. This post questions whether ANY lube in the lube grooves of a cast bullet may alter it's accuracy. This thinking was brought on after reading an article by my good friend George Carlson (georgewxxx) posted on the CASTING FELLOWS website. George comments on how he has observed traces of lube that had been spun out of the lube grooves of cast bullets, both on paper targets and also spattered on his chronograph. I too have noticed this. Could it be possible that this loss of lube by centrifugal force cause a bullet to become rotationally unbalanced? Think of a wheel on an automobile that loses a major wheel weight. That wheel goes out of balance and can cause shimmy, bumping or thumping. Assume that we pressure force lube evenly into the lube groove(s) of a bullet and that it is rotationally "balanced". It only stands to reason that as lube is expelled due to rotational forces it most likely is not expelled in an even manner, causing the bullet to become unbalanced. Without doubt we have all seen the remnants of truck tires on the highways that have had a re-cap come apart. Perhaps we have even had this experience on a personal vehicle. When this happens there is a whole lot of shimmy, shake, bump and thump as the ill fated tire goes through rapid stages of becoming unbalanced, as it sheds pieces. I believe this same thing happens to our cast bullets. Harry Pope was of the opinion that the base of a bullet is the "steering" end. The lube grooves are on this end of the bullet. It would then seem likely that unbalancing the "steering" end will effect the bullets flight. I harken back to some shooting I did years ago. The rifle was a "sporterized .30-40 Krag with an old Pacific peep sight. The bullet was Lyman 308299 heat treated WW, lubed with Lee Liguid Alox. Powder was 4759. Estimated velocity was about 1800fps. The 200 yd groups would be VERY competitive in CBA military rifle competition, today. This was my only use of LAL. Now I am beginning to wonder! Are lubes such as Lal, Rooster Jacket, X-Lox, teflon or moly another key to better accuracy with cast? I probably will not ever be able to wring out a definite answer to this. I'm stacking a lot of years on myself and there seems to be more and more honey-do's and round tuits. Perhaps one of our devoted casting clan will pick up the challenge and come up with an answer. Happy casting. :?:

44man
05-18-2009, 08:43 AM
It is correct that chunks of a hard brittle lube will spin out of a boolit when it leaves the muzzle. Even if the other lube eventually comes out, the damage to balance has been done.
I use soft, sticky lube that I hope, spins out evenly. I don't think it matters if all of it spins out or if all of it stays in the grooves but to lose half only sure will ruin groups.
It is messy and I get lube everywhere, even on the press handles. I have to clean dies often but I have to wonder if my choice of lube is the reason I shoot such small revolver groups. As I try harder lubes, groups open so I really think there is a limit to how hard a lube should be. To make it very hard so everything stays clean, like the stuff on store bought boolits, just might ruin accuracy even if there is no leading in the bore.
Many love LLA but with what I shoot, it leads the crap out of my bores and has not proven accurate enough for me. I suppose it works with certain applications just like many other lubes.
I have always stressed that lubes must be tested with many, many groups from the gun you use and that what you use might work different then from another gun.
The big problem is a lot of guys test lube from different makers but the only difference between them will be the color, not the formulation. So they see no improvement in groups, only that the boolit might be pretty with red lube or blue instead of black.
I guess what I am saying is if you make 50-50 or buy 50-50 from every lube maker in the world, you are still testing the same against the same. That is NOT what I mean when saying lubes must be tested. What the lube is made from and the hardness of each is what needs tested.

Larry Gibson
05-18-2009, 09:38 AM
I also believe this assumption is correct.

Larry Gibson

mrbill2
05-18-2009, 10:05 AM
I have read about this before and my question is this. How do we know that your bullets are in perfect balance before we lube the bullets ? When I weight my bullets and there is a difference in weight, it's hard to believe they could all be balanced. Without some way of testing bullet for balance, I don't think we can assume that the bullet is in perfect balance when it drops from the mold. Are the gas checks in balance ?
Just My $.02
Mr Bill2

felix
05-18-2009, 10:23 AM
Gas checks, paper checks/jackets, can be ignored because the "jacket" material is thin and does not have enough weight in itself when compared to lead, the body of the object. WW on a tire is the converse of what is here, and that makes it significant. ... felix

jonk
05-18-2009, 10:37 AM
I have recovered bullets fired up to 2100 fps using regular old 50/50 lube, feelix, LLA, etc.

Generally speaking the lube was all still there with the feelix and LLA. For the 50/50, on cold days, all there; on hot summer days, not.

However I really don't much care because:

1. The proof is in the pudding- or shooting in this case.
2. Shooting anything is fun, ergo testing accuracy of various lubes- whatever they may do in terms of flying off or not- is fun.

:)

JSnover
05-18-2009, 10:53 AM
Soft and sticky should be most consistent. If you shoot a hard lube and it's keeping you awake at night, try this: Lube and size 5 or ten boolits. Pick half the lube out of the grooves, weigh it, average it out (I guess a worst case scenario would be to have all the lube fly off one side, right?) Compare that with the average weight of your boolit. Probably doesn't equal more than 2 or 3 tenths of 1 per cent.

dubber123
05-18-2009, 11:29 AM
Soft and sticky should be most consistent. If you shoot a hard lube and it's keeping you awake at night, try this: Lube and size 5 or ten boolits. Pick half the lube out of the grooves, weigh it, average it out (I guess a worst case scenario would be to have all the lube fly off one side, right?) Compare that with the average weight of your boolit. Probably doesn't equal more than 2 or 3 tenths of 1 per cent.

This is essentially correct, but it however ignores RPM. A 1oz wheelweight missing from a 60 Lb. wheel/tire combo exerts many pounds of force. The weight itself seems insignificant, but at 60 mph, it exerts enough force to shake a 3,500 lb. vehicle. I would have to assume it does the same to a boolit at it's much higher RPM.

44man
05-18-2009, 11:35 AM
Soft and sticky should be most consistent. If you shoot a hard lube and it's keeping you awake at night, try this: Lube and size 5 or ten boolits. Pick half the lube out of the grooves, weigh it, average it out (I guess a worst case scenario would be to have all the lube fly off one side, right?) Compare that with the average weight of your boolit. Probably doesn't equal more than 2 or 3 tenths of 1 per cent.
How much out of balance is needed with a boolit spinning at 72,000 rpm's up to maybe 120,000 rpms????? I don't see where you feel it is not important.
What would your car tire do if spun that fast with 2 or 3 tenths of 1 percent out of balance. I think the tire might wind up inside the car with you.
You fail to realize that a small weight difference in a boolit can be caused by lead and mold temperatures and as long as there ARE NO VOIDS in the boolit they will shoot exactly the same. I am sure you would not shoot boolits with known air pockets in them.
The faster an object spins the more in balance it must be or it will destruct or go crazy.

44man
05-18-2009, 11:40 AM
I have read about this before and my question is this. How do we know that your bullets are in perfect balance before we lube the bullets ? When I weight my bullets and there is a difference in weight, it's hard to believe they could all be balanced. Without some way of testing bullet for balance, I don't think we can assume that the bullet is in perfect balance when it drops from the mold. Are the gas checks in balance ?
Just My $.02
Mr Bill2
Proper casting technique will not allow voids but a small temperature difference can cause a small weight difference that will mean nothing.
Actually, a jacketed bullet can be more out of balance then cast due to a difference in jacket thickness from side to side.

JSnover
05-18-2009, 11:53 AM
Never said rpms weren't important. But here's the thing: Any formulas for stability will change as the velocity falls and as lube flies off. You really can't predict how much lube will be lost or where it will come from or when it will come off. You also will have a hard time measuring it after the fact unless you have a clean backstop and you're sure that the missing lube departed in flight, instead of upon impact. If you know for a fact that you recovered your own boolits and all of the grooves are still full, it's a no-brainer; You don't have to worry about it. If it can't be predicted, maybe it can be measured. But if it can't be predicted or measured, try to control it. Bottom line is if you think your favorite load could be better and if you think the lube could be the problem.... try a different lube.

Dye
05-18-2009, 03:33 PM
How many revolutions does a bullet make in 100 yds @ 1800fps and 1-10 twist.

Dye

JSnover
05-18-2009, 03:41 PM
360 +. RPMs don't fall off as quickly as velocity does

Larry Gibson
05-18-2009, 04:13 PM
The centrafugal force that spins the lube off also is dependat on velocity (time) not just distance. The front screen of my skyscreens at 15' from the muzzle is now covered with lots of spun of Javelina, 2700+, LBT regular and soft and Carnauba Red along with some other assortments of lubes.

Larry Gibson

JSnover
05-18-2009, 04:41 PM
The best solution to this 'problem' would be to find a boolit design/lube combo that would either hold all of the lube all the way to the target or sling all of it off as soon as it leave the bore. I've seen plenty in the berm that seem to be full when they hit the dirt, just never bothered to clean them up to see what shape the grooves were.

44man
05-18-2009, 06:25 PM
Like I said, spin off or all stay on, it's OK. Only bad if a chunk comes off one side only.
It is like the liquid filled ring in a front loading washing machine. The liquid goes where needed when the tub spins to balance the tub. The right lube will spin off evenly instead of breaking.

mrbill2
05-18-2009, 09:49 PM
Proper casting technique will not allow voids but a small temperature difference can cause a small weight difference that will mean nothing.
Actually, a jacketed bullet can be more out of balance then cast due to a difference in jacket thickness from side to side.

Not according to Felix:

"Gas checks, paper checks/jackets, can be ignored because the "jacket" material is thin and does not have enough weight in itself when compared to lead, the body of the object."

How about the guy that Beagles his mold and that makes the bullet shoot better. Talk about a bullet being out of balance. He just shimmed the mold and now the bullet isn't even round. But some say that doesn't matter , it will be round when it comes out the barrel.
Mr. Bill

44man
05-19-2009, 08:47 AM
Not according to Felix:

"Gas checks, paper checks/jackets, can be ignored because the "jacket" material is thin and does not have enough weight in itself when compared to lead, the body of the object."

How about the guy that Beagles his mold and that makes the bullet shoot better. Talk about a bullet being out of balance. He just shimmed the mold and now the bullet isn't even round. But some say that doesn't matter , it will be round when it comes out the barrel.
Mr. Bill
That is mostly true and it seems a cast boolit can have a lot done to it without much harm. But remember the fellow that designed the machine he could spin jacketed bullets in? I can't recall the name, but he found some pretty bad bullets. I understand many of the bullet makers are using it. Sadly it will not work with lead.
However, after he sorted bullets, accuracy went way up.
Remember also there are not many that shoot long range with cast and those that do or shoot BR are very fussy with their boolits.
I would just guess that 90% of all cast are shot at 25 yards or less.
But the way I feel about it is if lube spins off evenly, it might even help balance, it is only the chunky stuff I don't trust and even though we are talking about very little weight, it still can't be good.
It is just too easy to make or buy a soft, sticky lube and never worry about it again. I know many of you get good results with 50-50 yet complain about store bought boolits. I have made some of them shoot by removing the hard lube and putting my stuff on them. Nothing worse then opening a box and finding half the lube out of the grooves.
As small of a thing it is, it still bothers me and is too easy to cure. After all, how many guys have said 1/10 grain more powder makes their .44 more accurate? :mrgreen:

mrbill2
05-20-2009, 08:06 AM
"That is mostly true and it seems a cast boolit can have a lot done to it without much harm."

I agree. Makes you wonder why we throw some bullets back in the pot.

"It is just too easy to make or buy a soft, sticky lube." What lube should I try. This would be for rifle bullets. I realy don't want to start making bullet lube.

"After all, how many guys have said 1/10 grain more powder makes their .44 more accurate?"
Kinda like the guy that think his bullets rise.

Mr. Bill2

303Guy
05-20-2009, 07:45 PM
I was hoping someone would have a comment on grooveless bullets and lube. The lube I have used is a 'hard' wax mix. (Candle wax hardness).

dubber123
05-21-2009, 01:29 AM
I was hoping someone would have a comment on grooveless bullets and lube. The lube I have used is a 'hard' wax mix. (Candle wax hardness).

I was amazed it worked at all. The one basically undamaged boolit looks good though, I don't see any melting, and the lands look sharp. How many rounds before accuracy falls off? Does it continue shooting that well?

303Guy
05-21-2009, 02:49 AM
I don't know. I only had seven rounds for testing and they all fell within the same sort of area. There was no leading. I take the view that if it can be done once it can be repeated and if seven rounds produces a clean bore then why not another seven! After all, for all the years I shot cast through my 44mag, I never had any leading at all. In fact, I never cleaned that gun! (By that I mean I never removed the grease that accumulated all over the place - I just kept on oiling it and wiping off the excess. I miss that gun! I sold it and it got stolen - at gun point - and I never got paid for it! Never sell things to relatives without cash up front! :mrgreen:) I have now taken to PP and still am in early days with that one.

Oh, I should mention that those grooveless boolits are tapered and that probably helps the surface lube to work!

http://i388.photobucket.com/albums/oo327/303Guy/MVC-503F.jpg

One should be able to see the taper in this pic. (This was an early days casting - since then I have improved the surface fish some. Not that it matters but they come out the mould easier!)

303Guy
05-21-2009, 03:01 AM
How do we know that your bullets are in perfect balance before we lube the bullets ?If I may attempt to anwer this one; The unbalanced bullet is actually dynamically ballanced in so far it will rotate about its centre of mass, not its centre of form. And because it is rotating with cetrifugal forces, it presents its areodynamic 'imbalance' equally in all directions, meaning it travels in a slight spiral path and ........ But you folks are actually an intelligent bunch so I don't need to say any more! :mrgreen: :drinks: