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
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- Location
- the chesterfield
Those are rookie numbers, we gotta get those numbers up!
