Raised area on parting line

[Rich22]

Good afternoon

I have a NOE 311247 that I am having an issue with. I am having some excess material on the parting line of the bullet and also some excess material at the base. I have sent the mold to Al and he gave it the once over and cast with it and it was good to go so it is obviously a technique issue. Mold looks like it is closing fine, I have played with the sprue plate tightness everything from easily opens with a bit of movement all the way until where it takes some decent effort. Bullets filling out well and they really do look good. Currently using COWW lead. preheating on a hot plate and casting around 700 and the mold is very hot when doing that. Only thing on the mold is bullplate spruelube added per instructions. Trying to figure out what I could be doing incorrectly and I am currently at a loss. Once this problem is done I will be good to go since these things are really very nice.

Thanks

[justingrosche]

If I had to guess,I would say excessive mold preheat. Your alloy temp sounds about right.
Another thing it could be is the blocks arent cooling enough between casts. This will be evident if your tearing a divot out of your bases when you open the sprue cutter. If this is the case, slow your cadence and/ or cool the blocks for a few seconds with a desk fan.

[Rich22]

Will grab pictures asap

1, do not believe I am pressure casting although I will have to read up on exactly what that it
2 Doubt it but cannot say for certain
3 Do not believe it is too hot because it seems any less heat either on the mold or alloy causes poor filling and overall bad performance
4 Dusty sent me a PM stating this could very well be the problem, I did not think of that and I will switch to a different set of handles when I cast tomorrow or the next day, that very well may be the issue right there.

[Rich22]

If I had to guess,I would say excessive mold preheat. Your alloy temp sounds about right.
Another thing it could be is the blocks arent cooling enough between casts. This will be evident if your tearing a divot out of your bases when you open the sprue cutter. If this is the case, slow your cadence and/ or cool the blocks for a few seconds with a desk fan.

I will give that a shot, it seems that I have had an issue before of having too little heat so I will try backing off a bit and see if that helps.

[justingrosche]

I will give that a shot, it seems that I have had an issue before of having too little heat so I will try backing off a bit and see if that helps.
That is one of the difficulties of aluminum molds, temperature regulation. They are not near as forgiving as brass or iron. In laymens terms, a much smaller happy place.

[Tatume]

Try tapping the handles as you close the mold, to give the mold an extra boost into the closed position. If it works, then you need to lube your mold. You're going to wear it out if you don't.

[John Boy]

... Try lubing the mold pins with paraffin. Then when you close the mold halves, squeeze the halves with your glove hand. With a stubborn mold, you'll hear a light - 'click'
If the halves are not completely closed, look in the sprue hole pointed towards a light. If you see daylight - the mold is not fully closed and fins will be on the parting line of the bullet

[detox]

I have an older aluminum NEI mould (renamed NOE?) 535gr .458 caliber that did the same thing. I sent it back and he returned it later with a sample boolit that he had cast with it. Sample boolit had pour band fillout because he casted colder to prevent raised parting line and whiskers. I never did get this mould to cast good bullets. I have been buying RCBS ever since.

[justingrosche]

If your getting FIN along the parting line, which I believe you are referring to as a raised section, that is a fault of block engagement. Whether its mold handles or alignment pins or lead on the face of the block, or compromised cavity edge, you will have determine that by eliminating the posiblities one at a time. If FLASH is whats occuring, where the bullets base extends beyond the shank its likely mold temp, alloy temp, or sprue plate tension or warpage.