Warped boolits?

[Jim]

A coupla' years back, I bought a 170 grain 6.5 cruise missile mold from Midsouth. I cast up a bunch of 'em, sized 'em, checked 'em, lubed 'em and put 'em in a zip lok bag.

This morning, I decided to load some to use as 'shooters'. Nothing special, just something to shoot, that's all. I grabbed a handfull outa' the bag and set up to start loading. I noticed one of the boolits looked 'funny'. Then I realized it was 'banana' shaped. Not bad, but enough I could see it without magnification. I started looking at the rest and discovered a large majority were bowed in the same manner. I know for a fact these boolits were NOT like that when I cast them. I did shoot some right after I made them initially and they shot fine.

Below is a photo of four that are typical of the rest. Any ideas what happened to these? I've stored other 'long for caliber' boolits for long periods of time and have never seen this. I'm really stumped on this one.

http://floydpics.files.wordpress.com/2012/04/dscn05801-e1334771261527.jpg

[swheeler]

Most likely you bent them when you put the gas checks on.

[Jim]

Most likely you bent them when you put the gas checks on.

Help me understand this. If I bent them when I sized and checked them, how come they did so well when I first made them? How come I didn't notice it when I was loading that first batch? Seems like I would have seen at least a few if I had bent them.

I stand on my original statement: They weren't like that when I first made them.

[BLTsandwedge]

Didja leave 'em on the rear window ledge of your car last summer?

[GRUMPA]

Jim,
I had the same issue with my 311291 mould waaaay back, I wanted to find out why I was getting flyers when I spent so much time getting the loads to shoot perfectly.

I know this is going to sound real anal to most but this took me weeks to figure out. I always water drop, I used WW and 2% tin. When I would cast them up mine were bowing but I couldn't detect it with the naked eye. I own a granite surface plate and the real expensive indicators with 1 of them being in graduations of .00005.

Come to find out that at the time of casting and dropping them in the water as soon as they cooled down enough to handle I would size them and the check for concentricity. Some came out with a T.I.R. (total indicator reading) of .0015 with most being over .005. The longer they just sat there the more they bowed.

The only thing I could think of was that the material was going into a relaxed state and bending itself. Made sense to me but I would just let them sit there for at least a week to stabilize and re-check with my indicators and pick out the best ones.

At first I thought it was my mould, I lapped it and did everything I could think of to it and the same thing happened.

With what I used for inspection I think I only got about a 1% keeper rate, but hey I'm real fussy when it comes to some things.

Heaven help you if you heat treat the things, that just takes a person back to step 1 and the process starts all over again.

[runfiverun]

the alox shrank but only of the heavily applied side where it took a year to dry.... :lol:
it looks like just the nose is bent.
i have seen long bolits bend from water dropping from the cooling rate difference.
you might have had a hot spot in the mold where the alloy hit it repeatedly.
and the crystaline nature from the antimony just took a while to be overcome.

[Jim]

Grumpa, that sounds like what might be happening with mine. But what the dickens is causing it? Without knowing the cause, how do I fix it?

By the way, these were cast from straight WWs, gently dropped on a cotton towel and air cooled.

[GRUMPA]

Jim,

The ONLY thing I can think of is that the material just isn't well placed or mixed at the time of pouring, that's just a guess. Just like most metals things can and will want to move to the weakest part.

After I got my 06 to do 1/2" at 100yds it went back into the cabinet and it's collecting dust at the moment. I did get a NOE 218gr through a group buy and that will be my next labor intensive project, like I need one.

I dropped (and still do) in water but first they hit floating sponges before they actually hit the bottom of the bucket.

As far as a 100% success rate? I never had that happen to me yet, I don't know if it's the style of the boolit or my methods but the best I got was 1% keepers. It may be that I'm a bit more than fussy I don't know. But I was determined to find out why I was getting flyers on my 06 when I spent a good couple of years working on the rifle itself.

I couldn't for the life of me get any more good boolits than 1% but when I was checking with my indicators they ran out TIR was .0004 with most over .001 but the bad ones were more like .017 and that was with stabilizing for a week.

I'm sorry I can't do any better than that for you, and I know your looking for concrete answers but I just can't give you an absolute answer.

[greenbud]

I would agree with Grumpa in the casting of my metal hammers I have had two over tim noicably bend. I make them out of very random lead and have seen them cast many different ways because of it.

[Jim]

Here's two more shots from different perspectives. In both, you can clearly see the bow. Boy, this sure has got me puzzled!

http://floydpics.files.wordpress.com/2012/04/dscn05871-e1334782925469.jpg

http://floydpics.files.wordpress.com/2012/04/dscn0586.jpg

[gwpercle]

This could also be the work of the infameous RELOADING GOBLINS . I swear they come out at night around my house and get on my bench and start fooling with the dies I have carefully adjusted. Then they cart off small tools and hide them, takes me hours to find them . Sometimes things just disappear and I will have to buy more... I swear that container of Bullseye was half full yesterday and now it's empty. You all have had things like that happen right ? I used to think it was one of my kids and blame them, but now they all live with someone else and the cat don't have thumbs so he can't do those things. So who's to blame for all the mischevious deeds , like bending boolits while you're sleeping ? I believe it to be the evil reloading GOBLINS but it could also be the reloading BROWNIES and/or reloading GNOMES...... thats my explaination and I"m sticking to it........gary

[steg]

Thats the excuse I use for missing, LOL

[Jim]

Oh well...................back in the pot I guess.

[Carolina Cast Bullets]

See, thats what ya get when ya try to make "missle" out of
a lead boolit. Mother Nature just dont like that idea

Jerry
Carolina Cast Bullets

[KYCaster]

No mystery there.

Different shrinkage due to different density.

As the boolit freezes on the surface first, the shrinkage pulls metal away from the still liquid center. In a perfect world the sprue puddle will provide the liquid to minimize this effect. In our imperfect world that's not often the case and we end up with a low density area at (we hope) the center of the boolit....but....with a two cavity mold the area where the cavities are closest will lose heat at a slower rate than other areas, leaving your low density area off center.

:drinks:

Jerry

[Jim]

No mystery there.

Different shrinkage due to different density.

As the boolit freezes on the surface first, the shrinkage pulls metal away from the still liquid center. In a perfect world the sprue puddle will provide the liquid to minimize this effect. In our imperfect world that's not often the case and we end up with a low density area at (we hope) the center of the boolit....but....with a two cavity mold the area where the cavities are closest will lose heat at a slower rate than other areas, leaving your low density area off center.

:drinks:

Jerry

And how long does it take for this warpage to manifest?

[Mk42gunner]

A coupla' years back, I bought a 170 grain 6.5 cruise missile mold from Midsouth. I cast up a bunch of 'em, sized 'em, checked 'em, lubed 'em and put 'em in a zip lok bag.

I look for simple and cheap fixes before going too deep into just about anything. With that said: You didn't have any other bags of bbolits piled on top of these, did you? Or said another way, juast how big was thew baggie of boolits?

Just an idea,

Robert

[geargnasher]

Jim, I've had the exact same thing happen with the exact same boolits. Two things I think cause it. Bending in the sizer, is, of course probably the #1 cause of bent boolits, especially the Lyman 450/4500 junkers with the lousy, oversize ram bores and loose ram fit. I had some UN sized, water dropped ones bend on me, I think it either happened as they peeled out of the mould blocks, impact with the water, or the result of being in one block a second longer than in the other block if I had to tap the mould to get them to fall out. If one side of the boolit is against the hot mould any longer than the other, they will quench in air or water unevenly, and this can cause them to "bananna" as they cool and begin to age.

I still think your main issue is happening in the sizer, though. Looking at the pics, it appears that many of them are slumped the worst in the unsupported nose portion, indicating the ram wobble sheared them sideways near the bottom of the stroke. Try using a flat top punch and sizing in little steps, lifting the ram gently off of the boolit nose three or four times through the process to equalize the side pressure on the boolit nose.

Gear

[MT Chambers]

Yup, with long thin bullets, out of line sizing equip. including nose punch.....it's a sizing thang.

[MT Gianni]

Gear, They look to me like they were sized with a Lee push through and a heavy coat of LLA applied.

[GRUMPA]

Gear, They look to me like they were sized with a Lee push through and a heavy coat of LLA applied.

That's how I do it (well except for LLA)
I size all of mine with the LEE push through sizer, then (after a week) (311291's) I checked and lubed them with LBT Blue.

To this day I don't ever size and lube at the same time.

[Jim]

I did in fact size and check them in a Lee push through. However, as I said before, I shot these boolits several times shortly after that and they were NOT warped.

Come on, guys, gimme a little credit here, will ya'? If I see they're warped when I got 'em out this afternoon, dontcha' think I would have seen that day one? Besides, if they were warped from the git go, how could I have shot decent groups with 'em?

I'm tellin' ya', this warping has occured since I stashed 'em several months ago.

[Michael J. Spangler]

it could be due to uneven cooling, the side that sits on the cotton cloth cools differently than the opposite side sitting up in the air.

ever see a japanese sword being made? a katana? they're pretty much straight when they're forged out and heated.

the back of the blade is coated in clay that insulates the spine, holding the heat causing slower cooling compared to the exposed edge.
when he blade is quenched in water the whole deal curves towards the spine giving it that sweet swoop to the blade (i think it's called sori)

maybe the uneven cooling is causing a little warpage as it fully crystalizes.

i know a little about metallurgy of steel and have seen first hand some the things heat and stress can do to steel, i imagine some of this must be true for lead. i've seen quenched blades get put down on a cold metal surface while a guy opened the door to the tempering oven and a few second later the blade snapped in half before he could pick it back up.

any metallurgist on here?

[beagle]

Yep! A sizer thing. You're either bending them when seating the GC or else while sizing due to missalignment of the ram/nose punch. It has happened to me on longer .25s and .22s and occasionally a .30.

Cure. Go with a nose first sizer. Either the Lee sizer or use an adapter for regular sizing dies like the perfesser is making. That bending is what started all this nose first adapter mess in the beginning and I'm a firm beleiver in it./beagle

[trk]

Jim -
I'll not assume that it was caused by a or b. It would be interesting to see if the results could be duplicated by any/all of the theories discussed here.

Cast 10 and pop out of the mould early, then late - compare if they are bent from impacting the towel if air cooled or the water if quenched.

Cast another lot. Store supported in a fassion so that 'sag' can be spotted and measured.

Cast another couple of lots - size by H&I die and compare those sized by push through.

Skeet shoot in May?

[geargnasher]

Gear, They look to me like they were sized with a Lee push through and a heavy coat of LLA applied.

Tumble-lubed, no doubt, but I assumed he seated the checks with a regular sizer. Lee doesn't make on that size anyway except on a custom basis, so it must be a custom one of some variety. I have to seat checks on the CM with some sort of press (usually drill press with top punch in the chuck) because my mould throws them a bit large and the GC shank is large enough I can't put Hornady checks on with my fingers.

Jim, I'm giving you all the same credit I give myself! I sized a bunch once before I noticed the slight bend in them, and discovered the they were bent even before lubing. I've also shot a lot of bent boolits to good effect, if the fit is good in the gun, those skinny, small-caliber boolits tend to straighten out when chambered as long as the nose isn't "bumped" too much to fit in the throat. One thing about the push-through die (depending on who makes it) is often the punch is too short to completly push the boolit through the constriction, so the next one in line has to do it, and that bumps the nose. Most of the Lee sizers don't have this problem, but some do. Just throwing ideas out there based on the info.

Gear

[KYCaster]

And how long does it take for this warpage to manifest?



Well Jim, I don't have ALL the answers. :oops:

Some of the guys here report dimension changes occurring over a period of weeks. I don't have any personal experience to confirm or deny it so just take it for what it's worth.....I tend to believe it till somebody proves otherwise.

What direction is the bend in relation to the parting lines? Do they bend toward a parting line? That would tend to lend a little credibility to my theory.

I've mentioned this a couple of times before and the idea doesn't seem to get much traction here, but based on what I saw when I worked in a foundry, shrinkage and the resulting variation in density is a fact of life. You may be able to minimize the effect, but it's almost impossible to eliminate it.

It isn't at all unusual for a sprue to be several times larger than the casting it feeds and that ratio is a huge consideration in the design of a mold. It's obviously desirable to reduce the amount of metal that will be recycled but not at the risk of a poor quality finished product.

The people who build the molds we use however, don't seem to consider that. Expecting a sprue that weighs 30-40 grains to supply a 175 gr. boolit that's 1 1/2 in. long is a bit optimistic IMO.

This would make a nice project for someone's next homework assignment. It's not very high on my priority list so I'll leave it up to somebody else.

As always, I have more questions than answers.

Thanks for listening.

Jerry

[PuppetZ]

It could be theorized that over the course of several years, the plastic deformation of the boolits caused by temperature change in their storage location and/or differential heating of the bullet material could cause a deformation like that. Similar to what someone described for the katana's blades.

As for fixing that, one could try running it through the sizer again. try a few, see how that goes.

[jblee10]

It seems to me that if it were a problem with alloy mixing that the boolits would bend at different areas. But those boolits all seem to be bent near the nose. Could it be that when you seated the gas check that very slight bending happened? And maybe that slight bending work softened one side, and it became exaggerated over time? I've never seen a difference in my boolits over time. But I'm going to start looking a lot closer now!

[Bret4207]

I didn't read all the posts Jim, but I've had a lot of bent boolits too. For me it seemed I was dropping them a little too soon from the mould. I cast fast, but I had to slow down. Not sure that's your issue, but it is for me.

I've also bent them in the sizer. People can't accept the sizer will produce out or round or bent boolits, but that's just what they can do.

[Bob Krack]

Here's two more shots from different perspectives. In both, you can clearly see the bow. Boy, this sure has got me puzzled!

http://floydpics.files.wordpress.com/2012/04/dscn05871-e1334782925469.jpg

http://floydpics.files.wordpress.com/2012/04/dscn0586.jpg

Jim,
The upper picture is for an uphill shot and the lower is is for a right hand (around the corner) shot. I just do NOT know how to duplicate that bow nor how to decide which one to load in advance... (giggle-giggle-tee-heeeeeee-hawwwww)

:bigsmyl2:

Bob

[popper]

I did some tests on WD and AC bullets, twisting in half and looking at the center core. The core is off-center! It is the cooling rate! I cast, size and 2 weeks later it is crooked enough to engrave the rifling on one side. They don't shoot very well. Now I WD and then oven HT to get straighter CBs. The different cooling rate on the sides of the CBs set up different alloys and different stresses. Results in bent CBs.

[Larry Gibson]

Jim

You are bending them during sizing and GC seating as mentioned. It is very easy to do and you didn't know about it because you did not know you could do it and thus weren't paying attention.

The longer, thinner and softer the bullet the easier it is to bend during sizing. Alloy and amount of sizing also make a difference as does the bullet sesign. Bullets with a scraper groove are easily susceptable to bending such as the 311284. Long skinny ones like the CM are also real easy to bend in a lubrasizer. I gave up trying to size the CM the regualr way in the 450 lubrasizer because the bullets easily bent. I took the I die out and used the H die as a push through. The I die stop assembly also had to be removed so the long bullets would drop out of the H die. The CMs were then easily pushed through the H die nose first and the GC seated and crimped just like with a Lee push through sizer. I then put the I die back in and pushed the last CM out. The H die was removed from the 450 and the stop assembly back in and then the H die. The CMs were then lubed the the regular way....voila, no bent bullets.

Larry Gibson

[popper]

I've gotten bent ones that have never been sized. Yes, you can bend them in the sizer AND make the nose large AND shorten the CB if sized base first (.40 WD).

[40Super]

Internal stresses in metals can move even steel around over time.We have a 5ftx5ft x6ft- 3inch thick angle plate at work I made fifteen years ago for on a boring mill that I've remachined square every three to four years since it was made.It is steadily moving over time(my bosses should have sent it out to be "stress relieved"in an oven). So long lead bullets can do so also.I would wonder if you cast more of them up and heat treated them in an oven, rather than WD,that the stresses would be more equalled. Just a thought.

[Sonnypie]

I like bullets like that.
If I'm shootin left, I turn the crook towards the right for windage correktion.
If I'm shootin right, I turn the crook towards the left for windage correktion.
And if there is a cross wind they fix that too. :veryconfu

[Jim]

Sonnypie, the men in the white coats are you're friends! [smilie=s:

[Larry Gibson]

Jim

Just read one of your previous posts so I see the lubrasizer wasn't used so my info doesn't apply. However, I did push through size mine and the lube with Javelina which doesn't dry out. Ever notice how when a wet old pair of leather gloves or boots dries out it shrinks and warps to one side? So what I think is the LLA, when it dried, warped that bullet. Notice how the warp goes in the direction of the most LLA? Well, LLA gets balmed for everything else that happens bad to cast bullets so why not that???

At least I know when coming up with that idea the men in the white coats will probably visit me right after Sonnypie:confused:

:drinks:

Larry Gibson

[Hang Fire]

Normal nose up process for sizing/lubing long skinny boolits is the culprit, If base first and boolit is not near perfect perpendicular and/or the nose punch is out of alignment, curvy boolits will result. The more one is sizing down the boolit, the more resistance, the more likely they will get bent. (Don’t ask how I know the above to be true for the cruise missile)

First, in lubrisizer, lube and seat GC nose up in a slightly over sized die which does not size the boolit. Then get a nose first sizing die from Lee (or turn Lyman type die upside down, several ways of doing so as discussed recently) and then size boolit nose first.

[Jim]

I found the problem: There's a loose screw behind the press!

I brought some 8MM loads with me when I came down for my next tour of duty. I had checked them base first. Sure enough, the nose was too fat to chamber. I got to lookin' them over carefully in a good light and discovered I had obturated the noses with the base first checking.

Big dummy.

[Larry Gibson]

Hmmmm, guess I wasn't too far wrong. That's what can happen with the 450/4500 with those softer long skinny bullets also. Same principle, just upside down with the lee push through.

Larry Gibson

[Char-Gar]

It is very easy to bend long slender bullets when sizing and checking them in a traditional lube/size machine that puts pressure on the nose. A nose first Lee type sizing won't bend the bullets. If my bullets look like that, that would be the cause.

I have never seen bullets warp with age.
I don't water drop so don't know the effect of hitting the water at an angle
I don't use LLA, so can't speak to that.

We don't have bent bullets with air cooling, push through sizing and conventional lube.

[felix]

Boolits should be hard as nails before sizing. Sizing should be done in stages when necessary. ... felix

[geargnasher]

Most likely you bent them when you put the gas checks on.

Actually, Larry, Scot was the first one to get it right in post #2 :holysheep

Gear

[303Guy]

I've had that happen. This was with a solid mold of uniform section but with more heat retention on the top to prevent the sprue and mold top cooling faster than the base. My mold was hot and so was the alloy and they were cast via a little funnel thing that poured straight down the middle of the mold and the sprue puddle cooled slowly, feeding metal into the shrinkage zone. Those things came out straight and went bananas quite soon. Only some mind you so obviously there was a degree of non-uniform cooling.

[209jones]

I have had big bullets bend when dropped onto a towel and a/c'd. They are still too soft coming out of the mould to hold shape. Water dropping into a floating rag seems to have cured that issue. The next issue I had was trying to size them and obturating the nose. Cured that with only going .001 on sizing at a time and letting the top punch float a bit. I use lube to hold it up in the ram.