Lyman 457191 mould with wheel weights and three weeks ago is making beautiful bullets all of a sudden I’m getting fins yesterday I have cleaned the mould face thoroughly and the little holes where the pins go into. I can’t figure it out but getting fins.
Lyman mold starting to get fins?
- Thread starter y2k
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BlackPowderBurner
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If the fins are thick, remove your mold from the handles and close it tightly with your fingers. Hold it up to the light, do you see any light coming through? If so, things need to be thoroughly inspected and maybe your pins need to be adjusted. If no light comes through, install your handles and do the same thing. If you see light when the mold has handles, that's a handle fitment issue.
Assuming you see no light when the handles are installed, and the fins are thin and can be scraped off, consider the following:
Are you pressure casting? That's where you force the sprue plate divets against the spout as you pour. That can cause finning. It can also be that you are finding the top end of your operating temp, if you slow your cadence after reaching the finning point, does it stop? I assume you are using a bottom pour pot. I find it much more difficult to get finning when ladle pouring.
If you do not have a manual on bullet casting I would highly suggest reading up on the subject. I have a couple digital copies you are welcome to. If you'd like, PM me your email address.
Assuming you see no light when the handles are installed, and the fins are thin and can be scraped off, consider the following:
Are you pressure casting? That's where you force the sprue plate divets against the spout as you pour. That can cause finning. It can also be that you are finding the top end of your operating temp, if you slow your cadence after reaching the finning point, does it stop? I assume you are using a bottom pour pot. I find it much more difficult to get finning when ladle pouring.
If you do not have a manual on bullet casting I would highly suggest reading up on the subject. I have a couple digital copies you are welcome to. If you'd like, PM me your email address.
Something is holding your mould open. Black powder burner is dead on. Using straight WW I would say too much pressure, too fast of a mould fill. Too high of a temperature. Assuming your faces are clean. Also happens with a higher tin content but WW shouldn’t have that high of tin content. Check for dirt around your pins.
if you've been lubricating your pins and pivots, you might have an accumulation of carbonized crud in the block alignment holes which is preventing the blocks from fully closing. it will be hard to detect because the amount of crud will be minimal, but enough to cause you some problems.
BlackPowderBurner
CGN frequent flyer
- Location
- the chesterfield
Those are rookie numbers, we gotta get those numbers up!
Check your vent lines for lead build up in them. I use a box cutter, very carefully, to push the little thread of lead into the cavity. A magnifier helps with this.
Draw a Qtip gently over the edges of the cavities. If there are any burrs on the edges, they will pull off fluff which is noticeable.
Check the alignment pins for rock. Rotate the mould faces so only one pin is engaged in its hole and see if it can wiggle. If it has any wiggle, the pin should be advanced a whisker.
Draw a Qtip gently over the edges of the cavities. If there are any burrs on the edges, they will pull off fluff which is noticeable.
Check the alignment pins for rock. Rotate the mould faces so only one pin is engaged in its hole and see if it can wiggle. If it has any wiggle, the pin should be advanced a whisker.
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Made a difference, not having it right up to the spout but it there’s still a bit of a seam or fins visible, and the same batch of lead and all that with Pedersoli moulds you can barely even tell you know see the seams are there’s absolutely no fins hardly visible
