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ead
01-04-2011, 02:38 PM
What causes tumbling minies or terrible inaccuracy? I've compiled a small list of known causes. Can anyone add to it?
1.Bullet too small for the bore.
2.Damaged muzzle crown.
3.Bullet base not square or not sharp.
4.Bullet alloy too hard
5.Bullet not expanding into rifling which can be caused by #1 or #2 or not using enough
powder.
6.Rate of twist (Rifling) not fast or slow enough for bullet style or shape.
7. Bad lube formula.
8. Minie skirt too thick or too thin for powder charge.
9. Lube too soft or too hard for outside air temperature.
10.Fouling build up (obliterating any advantage of having rifling at all.)
11.Bad bore. Pitting or bad machining in lands or grooves or both.
12.Improperly sized Minie.

DAVE FRANCE
01-04-2011, 03:10 PM
I shot some Sharps rounds once with a different lube from what I had been using. It was one of the crayon type lubes, with a bright color. It is fairly well known that those lubes will not work well with blacke powder, but will work with smokeless powder. I think the black powder is not hot enough to soften the lube enough to work well.

If a bullet is only marginally stabile, cold weather, or rainy weather may cause it to tumble.

I shot a bullet that was similar to a maxi ball that would work fine in warm weather but would keyhole at low temperatures.

David

ead
01-04-2011, 03:37 PM
Wow Dave, That's amazing. I never thought about the air density being a factor but it makes perfect sense. I have always wondered about how rain would affect a bullets path and stability. I agree that most smokeless lubes seem to usually be worthless for black powder. I've never used it but Alox seems to be an exception at least for smoothbores.

efritz
01-04-2011, 04:31 PM
Happened to me once with a Numerich 3 bander tearing skirts on a trash can style wadcutter. Still use that bullet today. Shot and shoots well with any other gun I've tried it in. Numerichs patent breech didn't work well with that bullet.

Gary Van Kauwenbergh, 101
01-04-2011, 05:06 PM
I'm not saying those other things can't cause tumbling, but in my experience, the most probable cause is hard lead.

It doesn't have to be wheel weight hard either. One year I cast over a thousand rounds with lead that passed the "thumb nail" test only to find they tumbled. That's the year I bought my LBT lead tester. The lead had a BHN reading of over 5, but less than 7. I had to recast everything. BTW, the colder lead gets, the harder it gets.

I worked in the Fire Direction Control Center of an artillery unit for four years on active duty in the Army. We calculated trajectories for the guns, and compensated for all kinds of things like how much the earth rotated beneath the round while it was in the air, the temperature of the powder, the temperature of the round, the temperature of the fuse, air density, wind direction, wind speed, variances in powder, variances in projectile weight, etc.

If you're trying to put it in a barrel ten miles away, all that stuff matters - but shooting off hand at 50 yards, most of it is academic.

DAVE FRANCE
01-04-2011, 09:03 PM
ead,

I used a lube that was alox and beeswax for over 20 years for Minies and other carbine rounds I used.

It worked for black powder very well, but it left a residue that got hard quickly with my Henry, so I started using something else.

A high temperature version came out that would melt at a higher temperature and I started using that on my Sharps carbine rounds.

A friend of mine used to shoot in Schutzen competition with cast bullets and black powder. He shot a perfect 200 out of 200 at 200 yards. All ten bullets were in a 4 inch diameter. He tested many lubes he bought and said several of them worked well.

I read a lot about lubes several years ago.

Someone mentioned bullets that tumbled that had a hardness of less than 8 on the LBT hardbness tester. I collected MInes from people and tested them for hardness. Some were 8, and worked well, but I think a heavy bullet with a heavy load of 3f might work and with another bullet that hard, and with a different charge and a lighter bullet, it might not.

The finger scratch test is not a good test. If you have a soft bullet and a hard bullet, and drop them on concrete, the sound they make is very different. The same with ingots. I think a sound test is better than a scratch test.

A lot of people have cast Minies that were too hard.

People say that petroleum products should not be used in lubes. Waxes and I think Mobil One oil are made from petroleum products, but they are not made the same way that regular oil is, etc. My memory might be wrong about this.

David

Lee Hoffecker
01-04-2011, 09:28 PM
Hello All,
One thing that I found that will cause a bullet to tumble thatno one else has mentioned is the thickness of the skirt.
I had a problem with the bullet not expanding enough to fully grip the rifling. I got a new base plug from John Dewalt
for my mold which cast a bullet with a deeper and thinner skirt. This solved the problem of minies tumbling.
Lee

ead
01-06-2011, 12:38 AM
Lee,
What mould were you using?

Joe Plakis, 9575V
01-06-2011, 09:34 AM
Regardless of what type of bullet you are using, unless you get the skirt to expand you will have tumbling bullets.

A ways back when I first bought my Whitacre barrel for my 63 Springfield I had a huge problem with tumbling minies. Problem was a size 580 bore, and sized 575 minies, 46 grains was not enough to expand the skirt enough to engage the rifling correctly. Even after going up to 578 and even 579, the 46 was still not enough, bullets flew out of the muzzle with a shotgun effect.

We had other problems with bullet molds. One that is well known is the RCBS hodgdon bullet, the skirt is too thick, 46 grains was not enough to get good accuracy, needed well over 55!. But after making up a new base plug that thinned the skirt, presto accuracy at 46 grains.

So both bore size and skirt thickness can be an issue! Or one or the other!

Joe Plakis, 9575V
01-06-2011, 09:34 AM
Regardless of what type of bullet you are using, unless you get the skirt to expand you will have tumbling bullets.

A ways back when I first bought my Whitacre barrel for my 63 Springfield I had a huge problem with tumbling minies. Problem was a size 580 bore, and sized 575 minies, 46 grains was not enough to expand the skirt enough to engage the rifling correctly. Even after going up to 578 and even 579, the 46 was still not enough, bullets flew out of the muzzle with a shotgun effect.

We had other problems with bullet molds. One that is well known is the RCBS hodgdon bullet, the skirt is too thick, 46 grains was not enough to get good accuracy, needed well over 55!. But after making up a new base plug that thinned the skirt, presto accuracy at 46 grains.

So both bore size and skirt thickness can be an issue! Or one or the other!

R. McAuley 3014V
01-06-2011, 03:21 PM
Joe,

Were you using double-fine (FFg) or triple-fine (FFFg) powder with those loads? I ask because I formerly had much the same problem with my P60 Enfield rifle, such that half my shots tumbled until the charge exceeded 55 grains, and the tumbling ceased at 60 grains. By merely changing the granulation from double-fine to triple-fine powder, not only was I able to reduce my load to 45 grains (less powder), there was no loss in accuracy and I also had fewer bruises from the recoil. Because triple-fine has a smaller sectional area it burns faster, so that the increased chamber pressure column of gas was nearly equal to the a larger quantity of double-fine which has a lower chamber pressure due to its slower burn rate. Thus, increasing the gas pressure column within the same volumetric space enabled me to very closely match the same pressure but with a lower volume of powder, and hence lowering the recoil, actually increasing my steadiness and deliverable accuracy. And as long as I could hold the rifle steady and on target, virtually every shot was in the same spot as the previous shot. This exact same load worked fine with the Lee ashcan, Lyman and Rapine 315 gr wadcutters, and Hodgdon bullet.

Joe Plakis, 9575V
01-06-2011, 03:43 PM
3f

ead
01-06-2011, 04:52 PM
Hey Joe and Richard,
Thanks for the info, by the way what kind of lube do you use. Since eventually fouling will cause inaccuracy good lubes appear to be essential.

DAVE FRANCE
01-06-2011, 05:58 PM
The best thing about 3f powder is that you can use it for revolvers, muskets, carbines, and the Henry.

Some firearm companies recommend 2f for calibers larger than 45 or 50, or whatever they choose. But they are worried about people shooting charges of 100 grains or more.

David

Greg Ogdan, 11444
01-07-2011, 10:09 AM
ead,
You don't know what a can of worms you have opened with the lube question! Many commercial lubes will work just fine. MCM and Grundy Brothers come to mind first. Also it never hurts to lube the cavity. I use Crisco which I have first melted to remove the air.

ead
01-07-2011, 02:15 PM
Greg,
You probably noticed by now that I love opening cans of worms. I can't use crisco out here on a hot day it's a terrible mess for me to handle. I was thinking of playing with the u.s military formula of beeswax and fat 50/50. But it might be too hard. I ordered MCM lube and a couple of sizing dies from Northeast traders a couple of months ago but It was never sent. Does anyone know what's in it. I might as well make it myself if I can't buy it.

R. McAuley 3014V
01-07-2011, 02:53 PM
Ead,

Several folks use Crisco not as their primary bullet lube but only inside the hollow base to assist in keeping the fouling soft during rapid-fire loading. I fill the base cavity with just a tad (about half full) for this purpose. Most use some other type of beeswax/wax/oil-based lube in the cannelures to reduce friction and windage in the bore. If you have the advantage of loading your ammunition in advance of a match (rather than at the last minute as some do), after about a month or so, the Crisco will loose some of its oils, and will dry out slightly. This may prevent the Crisco from melting as badly as freshly lubed tends to do. Of course, if you happen to be shooting in Emory Morgan's backyard (in Aberdeen, MS) over the July 4th weekend when it's upwards of 100 degrees in the shade, it might be a little messy.

John Holland
01-07-2011, 04:23 PM
ead -

After the tube has the powder and minnie in it, nose down, I just fill the base cavity with Crisco and wipe some of it around the grease grooves. Of course, I live in the North Land where nothing melts. My Southern friends tell me you can't do that down there!We have heating systems....they have air conditioners!

With this method I can fire an entire rapid fire skirmish without any need to wipe the bore in between events. Accuracy doesn't change from the first shot to the last.

JDH

DAVE FRANCE
01-07-2011, 06:21 PM
I used Crisco in the base when I started skirmishing. But, I found it could get hot enought to melt the Crisco even in the frozen North (Michigan) where I lived then. some people kept Crisco in a insulated container, so they could add it at the last minute.

Eventually I changed to lithium grease, just in the base, and it did the same thing and in doesn't go bad.

David

DAVE FRANCE
01-07-2011, 06:24 PM
Bees wax and Mobil One oil works fine and it is cheap. And it doesn't go bad. It is sticky when first applied to the bullet, but it is easy to handle if you wait a few days to load your ammunition. It doesn't melt in hot weather either.

David

ead
01-07-2011, 11:45 PM
Dear Brothers in arms,

I don't make a big deal out of using modern materials (ingredients) only because historical ingredients are sometimes scarce, but I'd sure like to find a lube with which I could make a period correct paper cartridge minie that wouldn't saturate the paper and not mess up the powder in all temperatures that we experience in all the temperature ranges in the the lower 48 states. I know this probably doesn't interest the typical NSSA shooter/competitor, but I'm primarily a historical shooter and I'd bet that deep down some of you are too. But I also love info from the NSSA skirimshers because I'm getting awesome info from them too , and let's face it the serious ones probably have fired more rounds than most Soldier's in the "War of Northern Aggression" ever did !!!!

Greg Ogdan, 11444
01-08-2011, 10:18 AM
ead,
Well, if historically correct is what you're after, you probably want a mixture of either beef or mutton tallow and bees wax. Start with a mixture of 50/50 and vary from there.
Can't offer any help on paper choice as we in the N-SSA aren't allowed to put that down the barrel of our muskets.

ead
01-08-2011, 10:40 AM
Thanks Greg,
I intend to try that formula just to have the experience of doing it the original way.

Southron Sr.
01-08-2011, 04:38 PM
In my experience, IF you have a bullet that loses a skirt in your breech, not only will it TUMBLE, but every suceeding round will leave its bullet's skirt in the breech and tumble.

The only cure is to remove the skirts from the gun's breech.

ead
01-08-2011, 11:37 PM
Southron,

I want to know what bullet or mould or bullet you had that was shedding it's skirt, So that no poor beginner buys it and has to suffer the same misery that you went through. Alot of people quit shooting because nobody has the intestinal fortitude (guts) to steer them in the right direction. I'm sorry but sometimes I get pissed in this world where people don't want to tell it like it is! I'm happy that you are willing to tell us that there are some products out there that may not be the best. Wow, I better get ahold of myself before the brain police come after me !!! I'd better put on my tinfoil hat and hide in the corner!!! :shock:

Greg Ogdan, 11444
01-10-2011, 10:10 AM
Ead,
Usually, skirts are shed due to casting issues; the mould or lead was not hot enough. Skirt separation seems to happen more often thth deep cavity, thin skirt designs. If you preheat the mould and cull out your first 10 or so bullets, the chance of haveing a separation. Just my $.02 worth.

DAVE FRANCE
01-10-2011, 11:29 AM
Ead,

Greg is correct. If you look under Northwest Region you will find a long article about casting bullets. It is about casting good quality large bullets (especially Minies) which is not always easy, and if you study the article it will probably help you make better bullets.

Let me give you a few suggesions.

Clean your mold before you start.

Smoke the inside with smoke from a carbide lamp or use a mold release. This is a big help.

Heat the mold externally before you start casting. No flame should go to the inside. (Probably not a good idea to preheat aluminum molds.)

Keep the lead hot, don't add a lot of lead at one time. It is a big help to have two pots. One you melt lead in and bring it up to the high temperature; then take lead from the first pot and put in the second one.

Different size bullets require different temperatures. Soft lead and Minies need higher temperatures.

Clean the lead and make ingots you don't have to flux. There is a lot of bad information about fluxing. Taking the oxidized lead off the top is a good thing to do, but not something you need to do every few minutes.

Someone did a test years ago and published the results. He heated a lead aloy with antimony and tin in it. He kept it at a hight temperature for days. It lost very little tin. You don't need to flux frequently to keep the tin in the mix from oxidizing.

Tin makes the melt pour better and makes casting easier.

Different techniques for different molds. Large Minies usually require a dipper to cast well. For solid bullets can use either a dipper or a bottom pour pot.

Some molds are not designed well. But, I have noticed Lyman molds has started using thicker sprue cutters in the past few years. Some molds are a lot easier to use than others. Minies with thin skirts make it more difficult to cast good bullets. Some molds will cast good Minies easily, and some will not.

If you can't find the article, I might be able to email it to you. I am fairly sure I have an old copy on a diskette.

The NRA Cast Bullet book is one of the few publications about casting that is good. Iis long out of print.

Aluminum molds are easily damaged or warped. they are strong at room temperature, but lose strength when hot and can warp. They have poor wear characteristics. I think all auto and truck engine blocks and cylinder heads have inserts or sleeves where the pistons or valves run against an aluminum surface becasue of the poor wear properties of aluminum.

There is no lead fumes from casting bullets. There are small particles that float around. Casting bullets is not nearly as likely to cause medical problems as some think.

Good luck!

David












David

ead
01-10-2011, 11:57 AM
Thanks Guys,
Sorry I jumped the gun in thinking it was the moulds fault. I'm thankful for your information as I'll be casting my first minies as soon as Northeast traders sends the supplies I ordered three months ago.