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IcerUSA
01-25-2008, 03:34 AM
What are some of the reasons for bad band fill out ?

Temp too high or too low ?

Not enough tin in the mix ?

Bad venting ?

Mould dirty with oil from maching ?

Reason for asking is I got one of the .323 plinkers for my 32 WS Marlin and I'm putting over 50% back in the pot , some of the better ones where heavally frosted and some not frosted at all , have cleaned the mould with carb cleaner, brake cleaner, and alcahol, so I think it's clean but then again ....

Thanks in advance for your advice .

Keith

Bass Ackward
01-25-2008, 07:23 AM
What are some of the reasons for bad band fill out ?

Temp too high or too low ?

Not enough tin in the mix ?

Bad venting ?

Mould dirty with oil from maching ?

Reason for asking is I got one of the .323 plinkers for my 32 WS Marlin and I'm putting over 50% back in the pot , some of the better ones where heavally frosted and some not frosted at all , have cleaned the mould with carb cleaner, brake cleaner, and alcahol, so I think it's clean but then again ....

Thanks in advance for your advice .

Keith


Keith,

Can be yes to all. Least likely is tin. Tin is over rated for fillout as temperature difference is the key.

One more that comes to mind, too hot of a mold from casting too fast.

UweJ
01-25-2008, 07:43 AM
Hello
Did you smoke the mold ? Donīt use a candle īcause itīs possible that you get wax in the cavity through the smoke.
Like Bass Ackward mentioned itīs very likely that itīs temperature. Do you have a steady rythm ?
Hope my 2 cents worth can be of help.
Uwe

Trapshooter
01-25-2008, 10:24 AM
I found that too slow a fill rate will also cause the problem. I use a Lee 10 pound pot, and in conjunction with the drips, some times the spout clogs up, reducing the flow rate to a trickle. I noticed the problem especially on a Lyman 452460. The bands weren't bad, but obviously rounded, which made the bullets light. Cranking the temp up helped a little, but clearing the spout solved the problem, and allowed faster work at a lower melt temperature.

Trapshooter

Bret4207
01-25-2008, 12:04 PM
BP or ladle? I have a few moulds that DEMAND an air gap pressure drop type fill, other need sprue to ladle contact. Just a thought. Also, is the sprue plate lose enough to allow good air escape? Sometimes rather than adding real venting and simple very light punch mark will work as a vent. If this is a Lee GB mould it should be more than adequately vented. If so you might read the "Leementing" stickies. Sometimes there's stuff in the cavities that'll cause poor fill out and drop out.

Bent Ramrod
01-25-2008, 01:11 PM
Sometimes the drill hole for the alignment pin will throw up a burr which blocks one of the vent lines. If it's adjacent to the bad fill-out band or on the bad fill-out side of the mould, I go after it with a needle file.

Sometimes there seems to be no reason, except a need for breaking in. On several of my moulds (and these were by no means new) that gave problems in the beginning, running the metal extra hot, pouring extra metal on the sprue plate and tapping the hinge joint as long as the sprue metal was liquid seemed to increase the percentage of good ones per session. (I would tell myself that I was settling the liquid metal in all the crevices of the cavity.) Leaving the hot mould open to cool after a casting session so the cavities can oxidize to a good purple or blue color seemed to help as well. Eventually, after three or four sessions of this, the moulds generally seem to straighten out, casting good boolits at normal temperatures.

If some of this seems like voodoo, so be it. Voodoo problems often demand voodoo solutions:mrgreen:.

IcerUSA
01-25-2008, 09:24 PM
Tried again today and they are looking better , thinking it just needs to break in , just don't like having to throw boolits back in the pot to recast what I just did I guess , will try a couple more times and see if it gets better , hope so .

Keith

GSM
01-28-2008, 12:56 PM
Keith:

Throwing the bad ones back in the pot isn't so bad. It's not like buying the bullets and having to accept low quality.