Lube, diameter, weight

[btroj]

A few recent discussions here have lead me to ask this- how do bullet diameter and weight change how a lube needs to behave?

I see huge differences in the behavior of Carnuba Red between my 45-70 and 32-20 in the cold. 32-20 is bad about cold barrel flyers, 45-70 doesn't seem to care.

Run mentioned in a different thread that lube plays a larger role in 22 rimfire than it does in centerfire cartridges. I tend to agree entirely.

I think that a lube with properties that work well with small diameter, light weight bullets will work well with heavier, larger diameter bullets. I don't think the same always follows.

Anyone else think small diameter, light bullets are pickier about lubes?

[RobS]

Yes I think that smaller calibers are more picky. I believe it's because of the lube groove diameters. The larger boolits seem to let go of the lube at the muzzle easier due ot the larger lube groove, well if the lube is soft enough by the end of the barrel to do it. The smaller calibers will hang on it seems and clear out to 100 yards on some of my past targets. I've had better luck with softer lubes and possibly less sticky that flow better from the lube grooves................just my thoughts anyway. The cold can really change a lubes abilities of coming off the boolit and a hotter day can take a lube and make it run or purge the barrel. Such a PITA!!!

[geargnasher]

Dang, Brad, you know how to open up a can of worms! :kidding:

As always, it's tough to draw broad conclusions like that since every particular part of the "system" of ammo and gun is unique. I do tend to agree with you, but I don't have any really firm understanding of why.

I do believe that balance affects long-range accuracy of small bores much less than with big bores, all other things being relatively equal, and I think that's because there's less diameter to get out of balance in the first place. We also tend to hold the accuracy standard the same for .22 and .45, so really we're doing quite well to have a .45 that groups less than a foot at 100 yards. The average shooter can push a .22 centerfire far faster with good accuracy than a .30 caliber or .35, even .45 although not many .45s go much over 2K fps and can still be fired from the shoulder.

Following that, lube does seem to be much more important to the smaller calibers, I think it's a matter of inertia and a stable system. Moving things with more mass are more consistent in motion than things with less mass. A skateboard rolling down the street will dart and jump at the least bit of influence, even a leaf on the pavement or a small pebble. A garbage truck can drive over the skate board and not even bounce, and takes many tons of force to make it turn a corner. A larger, heavier boolit is going to plow down the bore with a lot of "push surface area" behind it and not be so affected by slight changes in bore fouling, while the little .32 is going to be much more susceptable to lube or powder fouling buildup or the changes that occur during its travel down the pipe. I realize that the bore surface area is proportionately larger with the bigger bores, so the influence of bore condition may seem proportionate, but my shooting experiences tells me that the effects are not quite the same, probably because something would have to be proportionately different about lube viscosity to make it the same. It's difficult to make a tiny gas engine work as a 4-cycle because it's dealing with the same air and fuel density as a car engine, but everything else is smaller. If you could reduce the fuel and air molecules by 1000 times in size, 1/2"-bore model aircraft engines would work great with four valves per cylinder and real spark plugs, but then we'd have to shrink the properties of electricity and the spark arc too. Same thing with lube, bigger bores have more boolit/barrel surface to contend with, but using the same lube in a smaller bore isn't quite the same thing because of molecule size.

Another thing might be the particular design of each boolit you're using in those guns. I assume the pressures are somewhat the same. A boolit with a scraper band and cleanout groove in front of it will behave differently with different lubes and powders than one that has an ogive tapering to full diameter. There are a lot of things like that which affect lube performance (like comparing lube groove depth and width as well as driving band width to land/groove depth and width proportion), so sometimes we can improve accuracy by altering our lubes, but exactly why a certain change had the effect it did is more difficult to understand, and the same lube alteration may not work as well for a different boolit design in the same gun, or in a different gun/boolit combination.

Gear

[btroj]

I agree entirely on the inertia idea. I think a lighter bullet, like a 1300 fps 120 grainer in the 32-20 is very easily affected by bore condition from previous shots. The 420 gr 45-70 at same velocity doesn't even notice that same bore condition.
Had not thought about bullet shape and how it plays a role. The two bullets I am using both have an ogive that rolls right into bore diameter. Other than a crimp groove there is no front driving band.

RobS, I actually have had more issues with my 45-70 bullets and lube goobers than any other caliber. I can always find bots of lube on my 100 yard target if I use carnuba red in that rifle. Saying that, I do think an even, consistant release of lube is important in accuracy. A bullet that is in and out of balance during flight isn't going to be as stable as one that remains in balance.

I suppose I am looking more at how does the bore condition from previous shots affect the bullet more than what happens after it leave the barrel. In other words- is a search for a lube that works over a wider range of temps somewhat caliber and bullet weight dependant?

Does one lube have a wider range of temps in which it works in one load/cartridge combo than in another? How big a difference?

Yes Gear, I do know how to,open a can of worms. Big old crawlers in this case. I may just go fishing!

[RobS]

I agree entirely on the inertia idea. I think a lighter bullet, like a 1300 fps 120 grainer in the 32-20 is very easily affected by bore condition from previous shots. The 420 gr 45-70 at same velocity doesn't even notice that same bore condition.
Had not thought about bullet shape and how it plays a role. The two bullets I am using both have an ogive that rolls right into bore diameter. Other than a crimp groove there is no front driving band.

RobS, I actually have had more issues with my 45-70 bullets and lube goobers than any other caliber. I can always find bots of lube on my 100 yard target if I use carnuba red in that rifle. Saying that, I do think an even, consistant release of lube is important in accuracy. A bullet that is in and out of balance during flight isn't going to be as stable as one that remains in balance.
I suppose I am looking more at how does the bore condition from previous shots affect the bullet more than what happens after it leave the barrel. In other words- is a search for a lube that works over a wider range of temps somewhat caliber and bullet weight dependant?

Does one lube have a wider range of temps in which it works in one load/cartridge combo than in another? How big a difference?

Yes Gear, I do know how to,open a can of worms. Big old crawlers in this case. I may just go fishing!

Yep I too had this issue with CR. It's a good lube when it comes off the boolit or..........stays on. I didn't have any issues with it in my handguns at 25-30 yards and then I went out to 50 yds and seen issues with lube splatter and accuracy issues. Additionally my 375 H&H did well with it in the hot summer and not so well in the cooler months. BAC was good in most weather temps but it too gave me fits during the dead of winter in the rifle. Regarding lube "spin off" I believe it's an all off at the muzzle or all stays on clear to the target for best accuracy. Personally I'm an all off near the muzzle guy because I've had better results this route. Finding a lube that does it all perfectly........................:???:

[geargnasher]

If you're getting lube on your 100-yard target, as Bill Engvall would say, "Here's your sign!" :kidding:

Lube is too hard, firm, or sticky, or something. C. Red works better with higher pressures and higher velocities because it actually leaves the muzzle. For what you're doing, and the pressures you're rifles are working with, you would probably be much better served with a very soft lube like LBT Blue or a soft version of Felix lube. That soap lube you're playing with might work out really well, too, as it can take the heat without losing too much viscosity or melting and running out, and Joe says it shoots well in the cold, too, the only problem is getting the formula right, which is tough since one of the ingredients is tough to duplicate and the proportions of the recipe are difficult to figure out exactly from instructions. Basically you need a softer lube that isn't too slick, and doesn't melt and run at 130F, yet isn't rock-hard and brittle at 30F. I think the soap lube will do that. Felix lube will almost do that, but not quite.

Gear