Casting problem - my first HP mold

[a.squibload]

Finally tried the HP pins in my NOE 429421.
Used the plain pins before, made good SWCs with it.
The HP pins usually release OK, but the mold doesn't want to release the boolits.
Had to apply a little force to get the mold open.
The side of the mold opposite the pins doesn't let go.
That makes the pins drag the boolit out of that side, and leaves marks from the
corners of the lube grooves.
Sometimes the boolit nose got ripped open.

This was all done gently, I'm not a mold beater! (No whacking.)

Alloy is 50/50 soft / WWs with a bit of tin.
Pot was running around 700º, I read laterin the instruction sheet that 600º is recommended
so I turned it down (my burner is kinda hard to adjust).
I tried casting faster, or slower, never got it right.

Since it made good boolits with the other pins I assume it's operator error
relating to HP technique.
Suggestions?

https://lh3.googleusercontent.com/-vt38Suk4rD0/T0yMa0wrKzI/AAAAAAAAAX4/ECmxaPKaPsw/s640/HP%2520mold%2520nicks.JPG

https://lh6.googleusercontent.com/-O90tsBKHfho/T0yMarVXggI/AAAAAAAAAXw/s_nTx3lYFpo/s640/HP%2520mold%2520nicks%25202.JPG

[Max Brand]

I would scrub the mould really good and turn the heat up some on the pot. I usually cast HP's at 750+ out of my bottom pour. It takes more heat to get those pins up to temperature and once they are you have to keep up a pretty steady pace to maintain the heat.

Max

[stubshaft]

I think you may be waiting a little too long to release the boolits. You have to cast fast and hot with HP's. I don't even look at them when i release them and save the culling for later.

[1Shirt]

Agree with Stubshaft! Cast as hot as you can, and as fast as you can, with as much of a timed sequence for consistancy as possible.
1Shirt!

[runfiverun]

that tear on the driving band is suggesting a burr in the cavity.
get a magnifying glass and look it over real good.
the open sooner and keep everything hot is a good suggestion,never mind what the pot temp is it's what ever you need it to be.
if thats 650 fine if you can cast that fast [4-5 per minute] if you can only do 2-3 then you need another way to keep things hot [mold/pin temp is more important than alloy temp]
if the boolits are sticking to the pin[s] you need to look at them for burrs or sharp edges or give them a coating of mold release.

[geargnasher]

I'd take a look at what R5R suggested. Assuming the boolits didn't stick in the cavities before, look at what changed. Did you cast with such a "mild" alloy before? You're casting with an alloy that I'll bet has a full-liquidus point of around 590-600 or so, so you'll need more heat than with WW metal, at least 700, 725 might be better. Keep it under 750 or you'll lose the oxide-barrier effect of any tin present, and the alloy won't fill as well. Cast fast to get the mould hot, those pins need to be VERY hot to work right, but the sticking in the opposite cavity sounds like a burr.

Gear

[MT Gianni]

Gear has just describe why I get my best HP from an alloy @ 740F.

[a.squibload]

Thanks guys, I think it's me that needs the tune-up!
Anyway this mold is basically brand new, couple hundred boolits.

Same alloy as before, but this time I had the "water heater skin wind shield",
requiring a couple steps around to the shelf where the drop zone is.
That few seconds walking back and forth could cause too much cooling
didn't think about it at the time.
I have since moved the shelf closer, will try it again at a faster pace.

Sure there are no burrs, have inspected the mold and have cast
nice SWC boolits from it.

Did some swage cores with a couple Lee 9mm molds the other night,
soft lead. Got in a rythm, they were jumping out. Most were shootable.