First time casting hollow points????

[msinc]

Been casting my own bullets since back in the late 70's...but last night was the first time I tried my hand at hollow points. I am seeing a void right in the bottom of the hollow point. It is as if there is something on the end of the hollow point "spear" {for lack of a better term} like oil maybe??? I cant see anything wrong or that doesn't belong, it looks bare and clean to me. The boolits came out perfect other than this. I never really noticed it before, but when I looked at some HP boolits I have that were cast by someone else they have it too. Different mold and caster. Some of these voids are bigger than others, some are small enough that I don't think it will cause any issues, but some are fairly good sized. Many of the boolits that I cast do not have the little void and really are perfect. Anyone have any ideas what causes this??? Or how can I get it to stop??? I am sure this has probably been asked before...I cant be the first idiot to get voids right in the center bottom of my hollow points. Thanks in advance for any info.

[runfiverun]

heat.
more heat.

[Tatume]

The spuds cool quickly. Some people keep a propane torch on the bench. Just before closing the mold pass the pins through the flame, and then promptly pour.

[msinc]

Thanks fellas...it did seem like the mold took a longer than usual time to get to temperature. I guess I should have added that it was also my first time casting with a steel mold. I ran the heat on the furnace way higher than I normally would with aluminum molds and never got a crystallized appearance on the surface. I got a lot of good ones though, so I must be close.

[44man]

Long ago when casting Minie' balls I ran into that and never found a cure. I heated the plug, raised temps and even cut vents on the plug. I poured every which way but it was always there.
The a friend gave me another size mold and with no extra effort, it cast perfect.
One of the reasons I don't cast HP's or bases.
Now I have borrowed HP molds that worked. A mystery even close to 70 years of casting eluded me.

[OS OK]

What caliber and lead hardness did you use?

Did you weigh the anomalies to a good HP and how much variance in weight were they?

Did you work any loads up and how did they mushroom?

[Harry O]

I cast a lot of hollow-points and also hollow-base bullets. You need to get the pin hotter. I rigged up a device that I put the removable pin in when I remove it from the mould. It holds the pin over a short candle. When I am done getting the bullet out and start the pin back in, it is hot enough so that the void you mention doesn't happen. Moulds with built in pins are harder to keep hot.

[OS OK]

I sat an old clamp on the saw blade to drop the pin in while I dumped the boolit and it worked just fine. This was my first attempt with hollow points and didn't want to rig a torch and wire hangar, I wanted to get to casting...it worked!
That's a 1,200 watt hot plate and you can see it wasn't turned up but almost 1/2 way. By the time the pot was ready the mold worked from the very first cast

.175230

[Tatume]

OS OK, nicely done!

[fredj338]

I have several HP molds, I found blunting the sharp point on the pin helps, doesn;t affect expansion at all.

[msinc]

What caliber and lead hardness did you use?

Did you weigh the anomalies to a good HP and how much variance in weight were they?

Did you work any loads up and how did they mushroom?


44 magnum and the mold is the Lyman Devastator 429640. Hardness was 13 BHN tested with a Lee tester...haven't got that far yet on the rest of it, but I will post asap.

[OS OK]

You can see my first go round with the HP's in this link here...Lyman 452423 HP...single cavity...new to me..."Any suggestions?" (http://castboolits.gunloads.com/showthread.php?314060-Lyman-452423-HP-single-cavity-new-to-me-quot-Any-suggestions-quot)

Today I cast another batch to fool around with, it was 9.2 BHN on the pour today, I hope that it remains low in 7 days, if so I'll do another load workup and hope to get them to mushroom well in the 1911, .45 ACP, low velocity heavyweight.

The first batch was 9.4 and increased to 11.4 today, 7 days later (IIRC) and weighed 233 grains avg.
Today they poured at 9.2 and avg. weight was 238-9, definately more lead in these, I hope they stay soft, we'll see?
The first batch had arsenic because of the COWW's...today they are only the SOWW's...no arsenic...I hope!

Your 13 BHN might work if you shoot them hot in a Ruger Blackhawk or equal. In a 1911 they'll be just fancy looking SWC's.

[Blackwater]

Run and OS OK have the basics down, and the only thing I can add is that in my experience at least, extra tin tended to give me better bullets. At 4% tin, they seemed to hold together in penetrating much more readily than if just using 1-2% tin. At 6%, I got about perfect bullet performance and great mushrooms with little to no tendency to shear the petals. Just real classic mushrooms and pretty consistent penetration. I stuck with 4% since I was in college and money was tight. They worked fine at that level on everything I shot with those bullets. More heat, nicely warm pins and a bit more tin, and I'm betting your problem goes completely away.

[runfiverun]

the cavity is from the alloy in that area freezing from hitting the cold pin.
it's just like the first bunch of boolits from a too cold mold.
I have seen lino-type 25 lb pigs that weigh 20 lbs from a big void in them from the alloy hitting the cold mold and swirling over itself freezing with a hole in the center.
the void is alloy that freezes too quickly and holds the hotter incoming alloy from settling into place around the pin.

[msinc]

I have several HP molds, I found blunting the sharp point on the pin helps, doesn;t affect expansion at all.

Thanks for the tip...this particular mold has a fairly wide flat on the tip of about 1/8", but the edge is sharp because the tip is flat...would it maybe be worth trying to put a radius on that flat edge????

[msinc]

Here is a photo of the cross section of the "worst offender" showing the hollow point void. Most of them with the void were no where near this bad...this boolit weighed in at 271 grains, the ones that appeared to be good boolits were within 1.5 grains each and they all weighed in at 278 grains, plus or minus the 1.5. That is gas checked and lubed ready to load. The bad ones were typically 2 grains or so lighter than the ones without any void. I also remembered that this is a different batch of lead so I retested the hardness for a BHN or 9 which seems more reasonable. I was surprised to see that other small void....

http://i47.photobucket.com/albums/f186/siebert77/P8260028_zpsbunqbbrm.jpg (http://s47.photobucket.com/user/siebert77/media/P8260028_zpsbunqbbrm.jpg.html)

[JWT]

I have cast hollow points using NOE, MP, and Lyman molds. The only one that I have some problems with the void is the Lyman 45 Devastator. Heating the pin certainly helps, but I wonder if the shape at the end of the pin is a contributor as well.

[Blackwater]

I think I'd listen to Run, and keep the metal, HP pin and sprue plate a little hotter. Casting HP's is definitely more of a challenge than casting solid bullets, but it's really no trick to learn. Just keep trying stuff and you'll teach yourself what works and what doesn't. But listen to Run and the others here, and you can cut that learning time in half, but some experimentation will always be part of learning to cast anything.

[msinc]

Yeah, I understand...I also should be clear that it wasn't like all or most of the boolits came out this way. Actually, after recycling the first 50 or so because of wrinkles I cast 250 more bullets. Probably only 50 of those had the void. I did turn up the furnace once to get the wrinkles to stop. I just don't know if that was the point at which I started getting all good ones or if it was intermittent the entire casting session. I really didn't notice the problem until I was done casting and doing the Q.C. check for which ones were good enough to consider loading.

[msinc]

So I actually went out this weekend and shot some of these bullets...the load was 20.0 grains of IMR4227. It chronographed at 1175 fps. I am running these through a 629 with an 8 3/8" barrel. This gun has a Taylor throat. I was very impressed with the accuracy, in fact I probably shot one of the best groups ever with this gun. 4 rounds in the same hole at 25 yards offhand...the other two were about 1 inch away. I did have two bullets keyhole...not sure what that was all about{????}, it only happened those two times out of 70 some rounds. Never had a handgun do that before.
As far as expansion...I fired one into a sand pile and it completely flattened but appeared to stay together.

[Blackwater]

Sounds to me like you're getting there. The keyholes could possibly have been bullets with voids in them, but it's unusual to find them grouping that closely with tumbling bullets. I don't know quite what to make of that part of it. But at least you're on the right track. Next session, try with the heat up a bit on the pot and the pin, and see if you still have the problem. That should likely be illustrative.

[OS OK]

Those keyholes must be rounds with voids and they get the center of pressure ahead of the center of gravity. That or when they spin up they are wobbling because the centerline balance is off to one side.

I dunnoh...charlie

[msinc]

It's a mystery to me...I first thought maybe the alloy at 9 was skipping over the rifling, but I also cast and shoot 240 Lee SWC boolits with and without gas checks and they work just fine at over 1500 FPS. The barrel is not leaded up, the lube seems to be working okay. I don't know how out of balance a boolit has to be to keyhole at 25 yards. This is the first time I ever really shot this gun at a paper target...most of the time I just shoot at dirt clods in the pit or skeet targets set up on the bank. Every now and then I get a "flyer" which may have been a keyhole or tumbler for all I know. I am going to do some more shooting at paper targets to see if it was a few flukes or something that happens on any regular basis.

[Nose Dive]

Agree... all tools... molds...alloy... spikes for hollow points...should be HOT TO TEMPERATURE....

And....

the alloy must be fluxed and mixed... "ingots' should be clean and dross removed...

I think the 'bubble' you show is from a poorly mixed alloy and not FLUXED and mixed before you poured your ingots.
or the alloy was cool when you poured it.

So...Advice....here goes nothing....

I don't know how and what you smelt. I smelt..."trash and corruption' from the depths of hatees. Yep...road kill here.

So...I am left with a smelt pot of grud. I flux with sawdust three times in each smelt batch. Mix well... 'filter' out clips,
trash, and corruption at low temp...say 700.... this is done over a layer of sawdust...I mean...i put sawdust in the bottom
of the pot,,,the add the smelt material...then get it to 700 and mix....SMOKE...SMOKE...SMOKE...I told you three times.

with all trash out...I add more sawdust and mix again....Now...if I have MY INGOTS...THAT I MADE...I might add one or two
to bring the level of the smelt pot up.....NEVER...EVER...EVER add "trash smelt materiel' to a hot liquid SMELT POT! Again,
I told you three times... OK..now...smelt pot hot.. all materials are liquid...guess what Joe Bob?... FLUX AGAIN with sawdust.
Yup...and mix well till smoking stops.... then Kidos....we add SULFUR to the pot slowly...yes... Elemental sulfur...now this
stuff is NOT THE STUFF from the flower shop. Or it could be if you added it to your sawdust. I 'roast' mine abit and remove
the H20... make it crystillane...then add it... (yes, I do buy it from the nursery)...now, your neighbors are calling the police..
SMELL...SMOKE...mix well... so..fluxed three times...sulfur treatment...now pour out in ingots.... Let cool in ingot pans...i
use cupcake pans.... once I can handle them...I put in CASTING POT....get it HOT...GET MOLDS HOT...GET HP POINT HOT...
Did I say all is HOT?... Now...get bucket of ICE WATER ready and get ICE to bottom of bucket with TOWEL and weights...
THis is the ALLOY you like yes? You Did add TIN... Lead... WW's...Pewter... solder....???? yes??? It MUST BE RIGHT NOW!

Don't use the casting pot as an alloy mixing pot... get all into ingots...then alloy in another pot...get the alloy right,,,then cast.

So...your favorite alloy is hot..tools are hot...pour the boolits...fill the spru... then cut it ...drop the boolits in COLD WATER.
Do it again...again...again...make sure HP Spike stays hot...again...again...until the Cast pot is EMPTY...then refill and bring
back to temp...and begin again...as above...

Once all boolits are cast and cold... ready sizing die and lubing die...size to desire...lube then too...(remeber...boolits are cold)..then box up and let set for a few months and then reload.... aging makes things settle down and 'soften up' a bit...that's why I do not use the NEW BEN's RED lube mix... the transmission fluid has aliphatics and they evaporate and the the lube 'cakes and cracks'... Not good for me... Now,,,I do use Ed's RED solvent mixture to clean my MILSURP Mauser's .... It does contain Dexron II or III...for said reasons...contains alphatics... But...this is a CLEANING mixture NOT a LUBRICATION mixture...

OK...my suggestions to remedy the 'bubbles'...No.1...as above...all tools, all alloys...hot!
No.2 Good...clean...fluxed alloy

Nose Dive

Cheap, Fast, Good. Kindly pick two.

[msinc]

Thanks for all the tips Nosedive!!! I do have a couple questions, first...you say, "aging makes things settle down and 'soften up' a bit..."
This seems like the opposite of what I have been hearing on this forum. I was to understand that the boolits got harder in BHN with time???

Next, I have always dropped my boolits in water right out of the mold, besides cooling them off quickly, what does this do to or for the boolit??? Does it anneal it {softer} or does it quench it as in temper or make it harder???

All of my boolit casting education came from an old book I believe written back in the early 70's titled, "Modern Handloading" by Maj. George C. Nonte, Jr. I have always followed what I read there...he said to flux with a "bullet sized lump of Alox"....at the risk of inciting a tree marking contest...when do you flux with bullet lube {or some form of wax} and when do you use sawdust??? I understand {maybe} that pine is best???
I always "render"{I am hopeful this is the correct word} my dirty lead outdoors in a big 1/2" thick aluminum half gallon gravy dish and I use that flux that Brownells sells...supposed to be "smokeless" and I guess for the most part it is. I have an unlimited supply of range lead that is just fired bullets and buckshot. The junk it contains is of course the copper jackets that float up and the occasional small piece of rubber, it think they use shredded tires. I really don't get much junk out of it when I do the melt for actually casting, but that don't mean there isn't some there. It is about time to "render" some more ingots so I will try fluxing with sawdust a minimum of 4 times, or until I see no more stuff float up. Thanks again for any info fellas!!!

[OS OK]

Find or grind a spoon type tool that will fit the contour of the interior walls of your smelt pot and when fluxing 'scrape' the bottom and sides of the pot...for some reason lots of gunk tends to hang on there. Any sawdust works, mine comes from inside the dust collector on the woodworking machines, it's a blend of every wood out there.
I think Nose mentioned to start out with a handfull of sawdust in the pot when you start melting...it will turn to carbon and seal the fresh lead from the air and help eliminate all the dross some of these guys are pulling off.
I save the dross from the pour pot and throw it into the smelt pot when making ingots...you get back Sn and Sb that way.