Filling Heavy Bullets?

[beng]

OK    What is the secret of filling a heavy bullet mould?   My 240s OK    300s OK, but when it comes to a 500 or 535 , something is wrong. (Lee & Lyman moulds)   The bullet itself will fill out good, size etc.   at the base I am getting small craters some with pin holes.   I have tryed the lead from 600 (will not fill good) to 800+  the mould is so hot it takes the lead sometime to solidify.   Bottom pore and ladle.   At the end of the pore at the sprue plate, the lead is just "sucked" down (only way I can call it)  Even if I go very slow on a hot mould, it will look good but when the mould is opened,   "craters"    Need help    beng

[Smokin Joe]

If the base is cratered, you're not letting the mold cool long enough before striking the sprue plate.

[srussell]

OK    What is the secret of filling a heavy bullet mould?   My 240s OK    300s OK, but when it comes to a 500 or 535 , something is wrong. (Lee & Lyman moulds)   The bullet itself will fill out good, size etc.   at the base I am getting small craters some with pin holes.   I have tryed the lead from 600 (will not fill good) to 800+  the mould is so hot it takes the lead sometime to solidify.   Bottom pore and ladle.   At the end of the pore at the sprue plate, the lead is just "sucked" down (only way I can call it)  Even if I go very slow on a hot mould, it will look good but when the mould is opened,   "craters"    Need help    beng

i would say that your not pouring enough lead for the sprue and as it cools it doesn't have enough lead to feel out. it wont hurt if lead gets on the sprue plate

[jhalcott]

 HOW MANY fills does this occur? IS the MOLD very hot? Are you ladling or botom pouring these bullets? IS the base "pitted" or is there a small cavity under the cutter? You MAY be casting with the sprue plate NOT hot enough, thereby cooling the lead as it flows thru. Also IF ladling, you may be taking too long to fill the mold. Try heating the mold AND sprue plate by throwing several casts and putting them back in the pot. Then use TWO molds alternating in filling one .Let it sit as you fill the other. THEN remove the sprue and empty the first mold. ALWAYS over fill these molds. Keep the melt above 700 degrees. IF you are getting evidence of ripping the lead from the base( not pitting) ,you are cutting to soon.
 one other thing to look for ,is the cutter sharp or dull? If the mold has been used to cut cold? lead it may have been dulled and is pulling the lead instead of cutting it
   Happy ground hog's day!!

[Lloyd Smale]

with large caliber 2 cav molds the spot that is the thinnest in the mold is between the two cavitys and if thats where your getting dished out bullets its because its becoming a hot spot. High tin alloys tend to be even worse offenders of this. What i do when casting real big bullets is cast the mold as a single cav and rotate cavitys every time.

[Nobade]

Are you keeping the ladle in contact with the sprue plate for a little while after the cavity is filled? I find that if I am not getting good fillout I can wait a second or two before pulling the ladle away and get much better bullets. Keeps the metal liquid and gives all the air a chance to vent off. 

[Richard P]

Bullets cool from the outside to the center. You must have a properly hot mould and properly hot alloy. You should pour a large enough sprue that there is a reservoir of metal so the center can draw from it as the bullet cools.
  Watch the new sprue. It will of course be shiny. When it turns gray/ dull and crystilline in color you can cut it. If you can cut it with a heavy glove, do so. If the base looks filled and flat you probably have made a good bullet.