Direction of filling 6 cyl has impact on quality

[Willbird]

I posted this on another thread, thought I would give it it's own thread,

has anybody else noticed with 6 cyl molds that filling them from one end or the other has an impact on bullet fillout ?? I have a 10mm TC and a 230 grain 452 roundnose that both act opposite, I was alternating directions of fill to try to equalise out heat in the blocks and noticed it.

The 4 cavity Saeco I have for a 125 grain round nose I usally fill away from me because I can get the fill spout closer to the blocks that way and I didnt notice any differance in fillout either way. I have run 5000 or so bullets from it so it is an old friend.

The Lee 6 cyl seem to like having 1/2-3/4 inch drop from the spout to the mold, and a pretty good stream strength to fillout all 6 cavities nicely.

All of this in a promelt run wide open with pure WW fluxed with 30w motor oil.

Bill

[Magnum Mike]

I dont have any 4 or 6 banger molds BUT i have noticed this on couple of my larger boolit 2 cav's. Both seem to have a preference toward having the rear cavity (closest to the handles) filled first in order to maintain base fill out. I figger that those handles are acting as a heat sink...

[Bass Ackward]

I dont have any 4 or 6 banger molds BUT i have noticed this on couple of my larger boolit 2 cav's. Both seem to have a preference toward having the rear cavity (closest to the handles) filled first in order to maintain base fill out. I figger that those handles are acting as a heat sink...


Mike,

I have a another possibility. I would bet that your sprue plate is a little tight and causing you a venting problem on the back cavity that is closest to the pivot.

The sprue plate should be lose enough to fall away pretty much of it's own weight when the mold get's warm. Therefore, the back cavity needs to be filled first, so that it can vent through the as of yet unfilled front cavity. And the front cavity vents through the blocks to the outside of the mold.

I will bet that if you took a small file or stone and put a nice small bevel on the top of the blocks on both sides of each cavity where they come together, , just enough that you see a shine for the bevel, that your quirkiness goes away.

For me, this is important because I rotate cavity fill as a way of controlling cavity heat. It helps me by molding more consistent, diameter bullets.

[beagle]

Same here on some 2 bangers. Must be the pivot screw acting as a heat sink. I have one that I have to alternate every 5 or 6 passes. If not, one end doesn't fill out./beagle

I dont have any 4 or 6 banger molds BUT i have noticed this on couple of my larger boolit 2 cav's. Both seem to have a preference toward having the rear cavity (closest to the handles) filled first in order to maintain base fill out. I figger that those handles are acting as a heat sink...

[45 2.1]

All filling problems are related to one of these: mold and/or lead aren't hot enough, oil wax contamination or venting isn't enough. Some of the problems with the LEE six cavities are the preservative, but once that is washed off the venting is it. If you notice, the stream of lead out of your furnace nozzle or dipper is pretty thick. Look at the different diameters on your sprue plates and compare them. If you pour a thinner stream directly into the sprue hole, without flooding it, where it can vent air for that little bit until it fills, you will pour very, very good bullets. This is especially helpfull when pouring long thin bullets. Try it, it will help.