Need some help

[plus1hdcp]

I am using a Lee six cavity in .401 for a 40 S&W. My reject ratio is extremely high. I get a good fill on both the closest and furthest cavity but the inside 4 cavities are hit or miss - mostly a miss. The bullets are rounding at the base. I have no idea why this is happening because on the same pout cavities 1 and 6 almost always have great results. Any ideas would be helpful because I am almost ready to return back to the 2 cavity?

[runfiverun]

sounds like you are starting out slow and ending slow with your pour slow down and give the middle ones a bt more sprue.
its either that or you are lining up the first and last two holes and only hitting the sides of the middle ones.
and the mold likes a bit of fill pressure.

[snaggdit]

How are you filling your 6 cavs? Are you lifting the pour individually for each cav or just moving the mold as each cav fills? If the latter, try individually. I had issues with the overflow from one cav starting to run into the next one and blocking the sprue hole resulting in partial fills. Just a thought.

[462]

For a test, how about filling just the four center cavities?

[plus1hdcp]

I'll try filling the four center holes for a check and report back.

I am using a bottom pour pot to fill and stop the stream after each fill. The boolit itself fill fine - good rounded top, crisp lube grooves, and rounded at the outside edges.

Thanks for the idea's.

[runfiverun]

you also might have a bent sprue cutter hold it up to a light and see if the middle holes are closer to the mold.
you can fix a venting issue here by stoning a light bevel on the mold corners.

[Bret4207]

You need to run the mould hotter. Either preheat it or cast much faster. The only other thing would be a venting issue, but R5R covered that.

[plus1hdcp]

I made an effort to speed up my casting and increased the heat from @ 650 to 700. This seemed to make all the difference in the world. I also ran the pot about 2/3 empty before adding the spent sprues back to the pot. Anyway, this was a great lesson for a new caster and thanks to all for your help. I am sure this is only the beginning of my questions.

[Bret4207]

650? Yeah, it needed to be a bit hotter than that. My current alloy in the SAECO BP becomes molten at right about 650-660. Yours may be different. There's a certain minimum level the pot temp has to reach, after that it seems to become mostly irrelevant. It has to be hot enough to stay nicely molten during the trip from pot to mould (ladle or BP) and stay in that condition long enough for the metal to fill the mould completely. A cool mould of course makes this more difficult. Much of my casting lately is done right around 700-720. I used to be up in the 800 area and above. Nothing wrong with that, especially for a ladle man, but lower temps work fine too. Once I figured out I needed to worry more about mould temp than pot temp things got a lot better and easier for me.