Sprue hole size?

[TacomaPete]

I recently bought a SAECO .44 GC Mag mold and though it is a good design it is very hard to cast with as most of the projectiles do not fill out completely which I put down to inadequate venting as it has vent lines on only one side of the block.

I then noticed the sprue holes are very small in comparison to my other molds, which all cast without any issues, whereas this one takes noticeably longer to fill the mold.

My questions are: Could the size of a sprue hole make that much of a difference and if it doesn't does that mean I have a faulty mold and it should have vent lines on both sides of the blocks?

Drilling the sprue plate to the same size as my other molds seems to be a logical first step.

[Winger Ed.]

Before I went chopping on a expensive mold, I try adding a little Tin, and/or raising the heat up a little,
as well as being sure the mold itself is hot enough. Leaving it sitting on a hot plate is pretty common.

I've noticed that as the boolit gets bigger & heavier, issues with filling go up too.
More heat is often a good solution.

[bosterr]

Slow down your pour. Give the air in the cavities time to escape.

[ascast]

or.. try holding the ladle right tight to the sprue in a sideways position. Then tilt them up together.

any zinc in that mix?

nver saw a mold with only one side vented. odd

[Dusty Bannister]

I had a problem with a SAECO #221 (225" 60 gr SP) ordered new several years ago. First the gas check shank was too short to allow fitting of the gas check. Then when they sent the correctly cut mold the sprue holes were too small and would not allow proper alloy flow unless pressure filled with a Bottom pour pot. I contacted them and found that they went to a smaller hole to get a flat bullet base. They sent a new plate with larger holes, but then that nearly covered the entire bullet base. Eventually I got a used left over plate with the small holes and only slightly enlarged the sprue holes, lapped and polished and that resolved the issue. It did not take much to enlarge the hole but go very small steps so you do not enlarge too much.

Venting? Some early Ideal molds were not vented at all, or only on one block. Instead of drilling on the plate, swap plates with another saeco mold and see if that solves the issue. If comparing holes with the Lee molds, remember that those one and two cav molds can be used with the open spoon type ladle but the sprue nub is huge.

[Ed_Shot]

With regard to venting, I'd also recommend that you adjust the tension on the sprue plate screw just to the point where the sprue plate swings freely by its own weight.

[stubshaft]

You do not need vent lines on both sides of the mold. I had a SAECO #430 (44 GC) mold with a tiny sprue hole. I drilled out the sprue hole and it worked perfectly.

[William Yanda]

Some have relieved the top edge of the blocks to aid venting. I believe this has been recommended for Al molds, I do not know if this has been tried with iron molds.

[TacomaPete]

Thanks very much for the replies.
I have a bottom pour pot and haven't had an issue with my other .44 mold not filling out (it is a steel 289 grain mold). I use virgin Lyman #2 alloy from a foundry so that is all good. I use a lead thermometer to ensure the melt is hot enough and the mold is up to temp.

It's a good mold and I don't want to give up on it so I'll loosen up the sprue plate a little to see if that helps then try enlarging the holes as others have said above.

[gwpercle]

Enlarging the sprue hole to the size of your other 44 mould should do the trick .
I find casting with a "Loose" sprue plate to be more trouble than it's worth ...
Lube the sprue plate and snug up the screw , it should open easily but not swing open of it's own weight ... that's too loose .
Gary

[toallmy]

I have had very good luck at just barely breaking the top inner edge of a mold that doesn't vent well .

[TacomaPete]

Update to my mold issue (not filling out).
I drilled out the sprue plate to match my other .44 cal mold and the difference now is like night and day. Mold fills out completely with sharp edges.
No need to relegate the mold to the unused firearm related items box now.
I'd post a pic however I don't know how to.

[Winger Ed.]

I'd post a pic however I don't know how to.

When you do a reply posting--

Near the bottom below the box to type in is a tab called 'go advanced'. Click it.
A new screen will pop up. look down it for 'manage attachments'. Click it.
A new small screen will pop up. Click 'add files'. Then click 'choose file'.
It'll open a box to your desk top. You can click on your picture file there, then click 'upload'.

That should work.
If it's too big or the wrong format for the site-- it'll tell you, and you can make adjustments from there.

[TacomaPete]

Thanks for the info on posting pics, I'll get onto it.

[TacomaPete]

Won't upload a pic. Pic is in jpeg and 2.3 mb.
Is the pic size too large?