mold fillout problems

[bpg76]

I have a rcbs 270 saa mold that i bought new in december.ive been having problems with the front driving band filling out completly.ive used the mold enough to where i can get the rest of the bullet filled out just get rounded edges and not completley formed front band about 50 to 75% of the time..this is my first iron mold..any tips and suggestions would be appreciated

[Duckiller]

Suggest you try increasing temperature of your melt or of you mold. Increased temp. aids in mold fillout. Every mold is different, but I have several molds that initially the bands don't fill out. Just keep casting till everything gets up to a proper temp. Have no idea what a proper temp is as a number ,just that mold fills out. I use a 10 lb. Lee with temp turned all the way up. Once boolits turn real frosty I gradually turn temp down. More to save elec. than objecting to frosty boolits.

[buck1]

You may try casting a little faster to heat the mold a bit more, and a trick that has helped me sometimes is to pour lead on the mold a little too long(big sprue).......Buck

[Trapshooter]

I had a similar problem with a keith style bullet, using a bottom pour furnace. If the spout was even a little plugged up, I would end up with rounded edges on part of the front band. I tried more tin, more temperature, more sailor talk, but nothing worked. I cleaned out the pot, and changed to a different lot of wheelweights. The bands were good for a while, then as the spout clogged up again, and the flow rate decreased the bad spots on the bands returned. It took a while to see the pattern, but eventually it sank in. I didn''t sorted out the "why", but the "what" is obvious to me now.

Trapshooter

[STP]

If your bottom pouring and getting fillout issues, try ladle pouring. Worked for me with several moulds...SC and DC.

[SharpsShooter]

First, crank up the heat on your alloy. Second, cast at a steady , smooth pace and get the mould hot. What you describe is a heat (or lack of heat) problem.


I use a bottom pour for boolits as small as 80gr 25 caliber and as large as 530gr 45 caliber with no problem regardless of single, double or 6 cavity.



SS

[bpg76]

thanks for the tips guys.what temperature range should i be trying using straight wheelweights with that mold?

[Texasflyboy]

Virtually all mould fillout problems for me have disappeared when the melt temp is 650F to 700F and the mould is preheated to the point where the bullets are heavily frosted with the first cast. After the first cast, allow the mould to cool in stages until it reaches a better operating temperature and you should have perfect fillout.

My indicator of square driving bands or square grease grooves being perfectly filled out is the mould usually can't be opened unless you tap the hinge screw.

YMMV.

[Crash_Corrigan]

Some guys even heat up the steel mold on a hot plate prior to casting. Turn up the control on the pot to max and use a heated mold. If they are filling out ok then turn down the temp a mite until the fill out is bad again. Play with the temperature and then make a note of it in your reloading log for future reference. I sometime find a perfect solution and I want to be able to duplicate it in the future and that is why I always make notations when I cast and reload. I cannot rely on my stinking memory anymore and I hate when I lose something. This is getting worse as I get older. Getting old ain't for sissies. Three things I do remember:
1-Never pass up the opportunity to use the john.
2-Never waste a woody.
3-Never trust a fart. :coffeecom

[bpg76]

i cast about 200 earlier this afternoon.i cranked up the heat a little more and was tryig to cast a little faster and keep a steady pace.was casting perfectly filled out bullets in no time and the kept on dropping like rain.i guess before i didnt have enough heat and was moving to slow in prior casting sessions.like i said before this is my first iron mold and i havent been casting quite a year yet,but i think im getting the hang of it.thanks for all the help guys

[chunkum]

If the extra heat still leaves you with less than optimum fill out, add about an ounce of tin to 7 - 10# of WW alloy. That usually resolves the issue.
c.