New Lyman mold isn't working so good.

[19Echo]

I have been using 4 Lee casting molds for over a year now. Have had only a few issues. After my friend at Stonewall Bullet Company stopped shipping, I assumed he went out of business, but no, he only sells local. I started casting because of this miss understanding from years ago. I bought 50,000 147 lead rd nose bullets from Robert per year and ran low a year ago and couldn't find a 9mm 147 rd nose mold like it.
I recently bought a Lyman 147 9mm rd flat nose mold. After 100 pours with this two cavity mold, I have one of the cavities that gives imperfections. One side of the bullet will be shinny and perfect. The opposite side will always be dull and rough. It was like this from the very first pour.

Should I just keep pouring and perhaps it will work out?

Would a thin layer of Molly spray help?

Never had this happen with Lee molds, so this is new to me.

[country gent]

How is the size of the bullets it drops? are they round and to size? Or oval and small? SOme of the new perservatives being used are harder to remove. You may want to cast up a few bullets drill a hole in the bottom and lightly polish this cavity with a little comet or metal polish ( Flitz Simichrome or fine jewelers rouge). drill a hole for a piece of keystock 1/8" or 3/16" to fit in snugly and super glue into bullet leaving an 1" or so sticking out. With a t-tap handle clamp the blocks with the coated bullet in a vise and slowly lightly work back and forth 204 times rotate 1/4 turn rotate back and forth again and rotate continue this for 2-4 rotations and check the cavity add a little oil and repeat. Work by hand and let the lapp do the work. On the back and forth think you are tapping a hole and breaking the chip.

[19Echo]

Bullets come out at .357". They are good except for those with the roughness on one side.
I cleaned the mold with hot water and a brush using Dawn and detergent with borax added. Then cleaned with denatured alcohol and a brush. Heated the mold with a torch to rid the water, and started casting.
I'm headed to my shop to do just what you said to polish the cavity.

I'm using tumble lube method and don't care for it much. Looking to buy a Star Lube Sizer when I get up some green.