What is causing this?

[MOA]

I'm getting some unusual marks on my cast boolits. New mold. Started getting these marks from the get go. Every boolit has a vertical groove going along the length of each boolit but only on one side, and a off center groove across the nose too. This mold is in my Master Caster machine.

Thanks in advance for y'all's help.

[quilbilly]

My first thought was that you might be opening the mold a little too fast is there isn't some imperfection in the mold. An extra 3-5 seconds of cooling time before you tap the sprue cutter might help. I am probably wrong.

[MOA]

My first thought was that you might be opening the mold a little too fast is there isn't some imperfection in the mold. An extra 3-5 seconds of cooling time before you tap the sprue cutter might help. I am probably wrong.

Thanks. I tried varying my time from 15 seconds after sprue changed color to 30 seconds. No change except back boolit started sticking more often in mold.

[MOA]

Base is not having a spur issue.

[TurnipEaterDown]

I don't think you would get those marks From the mold unless you saw some sort of feature (defect) In the mold that was rather obvious.
Have you looked into how the bullets are dropping from the mold? I have gotten odd marks on bullets from hang up during release, and they are usually lines on the body, and tipped to axis of bullet.

[megasupermagnum]

Those marks are from the mold opening crooked. More than likely you have a cavity that is sticking on one end. Every band looks rounded, so I suggest you either increase cadence, or increase pot temp.

[BK7saum]

Looks like the mold has opened and then the block hits the bullet and dents it on one side before the bullet drops out.

[swOhioMatt]

Is this the first time you’ve seen this and only with this mold? I ask because it looks like pinching caused by the mold opening same time the sprue cuts. Imagine not holding the handles closed tight when striking the sprue. Are your guide rails adjusted to keep squeezing the mold shut as the sprue cuts?

[MOA]

This was my first run with the mold. It just arrived in the mail last week. First chance to set it up in the Master Caster. Everything seems to be adjusted correctly. I will check on the opening timing but the spru cutting takes place at a specific location on the carriers travel. The spru is cut just before the mold is opened by the carrier making contact with the spring tensioner opening plate. I've got 14 other molds for this machine and never had this kind of problem with any of the other molds.

I'm planning on the next run to do the pour and move the carrier forward so I can manually cut the spru. Then open the mold very slowly an just enough where I can use a awl to pick the boolits out of the mold separately. That way I'll be able to inspect for any marks.

[John Boy]

Send an email with a couple pictures to Master Caster.
Probably the majority of us don’t own a Master Caster

[fredj338]

This happens on a couple of my molds on the magma. Try lubing the mold pins up, make sure nothing is causing the mold halves to slightly misalign.

[MOA]

This happens on a couple of my molds on the magma. Try lubing the mold pins up, make sure nothing is causing the mold halves to slightly misalign.

Thanks for that info. I'll check the pins.

[JonB_in_Glencoe]

Base is not having a spur issue.

The Sprue is off center.
I wonder if that can cause a problem to make that block edge mark on the side of your boolits.

[MOA]

Thanks JonB. I did notice that, and I'll check with some other sprue plates I have on hand.

[Hootmix]

I'd pour a couple w/ a dipper, and see how they look, then ck the pins on mould to make sure they are in line. OR,, the timing of the MC arms are not in opening together.

coffee's ready, Hootmix.

[FLINTNFIRE]

Looks like you are hitting the sprue plate or a edge of the mold , I dump mine on a well padded cushion with a ramp to the collection tray .

But rejects are always able for casting again .

[MOA]

I'd pour a couple w/ a dipper, and see how they look, then ck the pins on mould to make sure they are in line. OR,, the timing of the MC arms are not in opening together.

coffee's ready, Hootmix.

Yes Hoot. I'm going to pour one an open mold where boolits can't hit anything. If it's marked it will go back to be remedied. Could be the pins are off where the mold is not lining up, though I doubt it. If it was I'd have marks in two places not one. I'm hoping the boolits are hitting something on the way out of the mold. But again it's on every boolit. The boolits come out of the mold and drop 10 inches into a 5 gallon bucket of water.

[MOA]

well, mystery solved. I now have a new mold. First mold sent back for replacement or fix. Initial mold was cut off center. Hope to be casting a new pile of these 38/357 WFN boolits next week or sooner if the wind will quit. Here's a look at the new mold. I've not mentioned the mold company for a reason. My reasoning is mistakes are part of life and I was taken care of in record time. A one week turnaround. Mailed the questionable problematic mold back on a Friday, it got to the mfg on Monday and I got a new mold back 8 days later onTuesday.

[MOA]

Nope. Mold cavities were NOT cut by Magma. In case your wondering. Magma supplied the blank blocks, but another company cut the cavities. All is now well. I'm sure I'll be getting great boolits now.