I HATE flash/fins

[creature]

I just got a brand new Lee 9mm mold today and went through all the steps to prepare it for use. Got the mold up to temp on my hot plate and began to pour. Damn fins on the nose of the bullet. I really have to squeeze the hell out of the handles to prevent it from happening. To the point that my forearm gets tired after a while.

Every once in a while I find a little bit of lead build up in the spot where the fin is occurring and I clean it out. I used some fine grit sand paper and very carefully toot it off. I know, I know, this is not ideal but I couldn't think of anything else I could use while the mold was hot. There was only one cavity where it was building up and others were having fins after I removed the buildup. The other cavities where not touched by the sandpaper so I know that it wasn't caused by using it.

Two questions:

How do you prevent fins from happening on your bullets?

How do you remove lead buildup on a hot mold without damaging it(I don't want to use sandpaper anymore).

[Afro408]

First question.
Are you using a bottom pour pot, with the sprue plate hard up against the nipple? There is a lot of hydraulic pressure in a full pot and this can cause finning. Try using a ladle pourer and see if it stops. I have a couple of moulds, that I can't fill directly from the bottom pour pot, because of the finning. Others are ok with it.

Just put a bit of bullet lube on the lead buildup on the mould and maybe brush it off with cotton rag.

[freebullet]

How many cavities is the mold? Does it have round alignment pins & bushings?

[creature]

Lee 6 cavity and it has cone shaped alignment pins. It is a bottom pour and is 1/2in or more from the spout.

[ku4hx]

This rarely happens to me any more. The apparent fix was to lube the alignment pins as Lee suggest; dry pins tended to disallow full mold closure.

[freebullet]

On 1 of the lee molds I had to use a small socket & small hammer seat the bushings better. On another I had to use fine sandpaper on the male cone bushing to smooth it up, & yes they need lube. A slight tap with yer welding glove covered hand on the bottom of the mold just as it closes can help alignment ymmv.

[ku4hx]

A slight tap with yer welding glove covered hand on the bottom of the mold just as it closes can help alignment ymmv.

Many years ago, I found this to be worth doing every time! The slight vibration of a gentle rap sort of settles the pins right into place.

[gunoil]

Lee may behave after you use it a while. I have a new NOE that made fins at first then quit. Order a (heavy metal) lyman 147 grain 4 cav mold. Just call lyman's 800#. See if you can get the smile off your face. I would drill and tap w/allen set screws in the lee mold on your vertical bolts that hold your spru plate. Order a brass 3 hole from tom at accurate molds. I am soon if i figure out what i want.

Mold lube from bayoubullets.net

http://www.midwayusa.com/product/743639/lyman-4-cavity-bullet-mold-356637-9mm-356-diameter-147-grain-flat-nose-bevel-base

http://i1113.photobucket.com/albums/k511/putt2012/E978945E-F42A-43DC-9727-1CE59E3979B0-27141-00001DB71AC595F6_zpsbada1886.jpg
drill and pin your lee handles like mold on right
http://i1113.photobucket.com/albums/k511/putt2012/22B97DFF-2029-40E7-A884-58BD7221FE7B-1426-000005D583988F78_zpsf17f794a.jpg

[creature]

I figured it out guys! My mold wasn't hot enough. Once I got that sucker good and hot it started dropping them real good. I was still getting a little flashing at the bottom but the fins on the nose of the bullet is gone.

Thanks for the responses guys, you all are awesome.

[Down South]

Are the boolits measuring the same diameter all the way around? I've had to lightly lap mould faces a time or two in the past to get rid of a high spot

[popper]

I use a wood tooth pick to remove the occasional lead spec from the faces & around the alignment cones, when the mould is HOT.

[prs]

I use a wood tooth pick to remove the occasional lead spec from the faces & around the alignment cones, when the mould is HOT.

I used to, but then found another very useful item that is a larger and easier to handle: the bamboo Ka-bob skewers from the grocer stores. They are very sharp and tough. Lots of good uses for them.

Lead on the inner faces and alignment pins not fully seated are things that I have had make flash on my boolits.

prs

[Maximumbob54]

The only time I've gotten fins is when I'm not squeazing the handles closed enough. After about an hour my hand is just getting tired and it's time for a break.

[freebullet]

I figured it out guys! My mold wasn't hot enough. Once I got that sucker good and hot it started dropping them real good. I was still getting a little flashing at the bottom but the fins on the nose of the bullet is gone.

Thanks for the responses guys, you all are awesome.

The flashing at the bottom could be a sprue plate tension issue. I've found my lee molds need the sprue plate fairly loose. In fact so loose the sprue bolt will work its way loose with use. Installing 6-32 set screws on a lee sprue bolt is easy and increases production significantly.

[creature]

The flashing at the bottom could be a sprue plate tension issue. I've found my lee molds need the sprue plate fairly loose. In fact so loose the sprue bolt will work its way loose with use. Installing 6-32 set screws on a lee sprue bolt is easy and increases production significantly.

Thanks you sir! Loosened up the sprue plate and bullets are now perfect. How did you put in the set screws? I wonder if I could just get one of thos bolts that have a hole in the head that you can put a wire through to keep it from working loose...