Hello everyone,

I have been experimenting with casting temperatures with my iron Accurate Molds. So far, I think a temp of about 725 is best. Tuesday, I thought I had one of my best casting sessions ever, until I had a chance (last night) to inspect the bullets. There was a problem with the bullets not wanting to drop, and upon inspection, a large percentage had damage from the attempts to dislodge a stubborn bullet from the mold. PHotos attached. I think there is a burr on the mold that is causing the problem. 
What is the best way to diagnose the problem?
If there is a burr, what is the best way to remove it?
Any suggestions would be appreciated!
Thanks!
Joe S

another shot

I'm curious, too.  Have this issue from time to time. Doesn't seem consistent.

Joe; what is your lead alloy?  I use 20:1 and cast at 800F.  I use aluminum Accurate Molds and if I heat them really good on a hot plate, they start producing very good castings quickly. Usually, a moderate whack with a wood stick drops the slug. (sometimes, two whacks  )

Someone once advised me to check the edges of the mold cavity halves for burs or "lips" at the edges and carefully remove them.  That did help with an iron mold I was having "dropping" issues with.

Mike.

I have found that for alum molds, I need a temp of about 850Deg, but for an iron mold, if the temp is over 750 I start to get lead seepage into the vent lines and fins,  which are  hard to remove in the grease grooves, so I am trying to keep below 750 for that reason. I found what appears to be the culprit, or at least one of them, this morning with my Optivisor. A burr at the base of the bullet cavity that extended into the cavity. No idea how that happened, I am very careful with my molds, but it was there plain as day. I removed it with a fine semi-circular honing stone, tried to be as conservative as possible in removing metal. Hope to try it this afternoon, will give a report and post photos of the mold if the problem is not fixed. 
I ran some of the scratched bullets through the lubrisizer, in most cases, the scratches get ironed out, will lube up a sample to test how they shoot and post the results. 
The bullets that dropped without problems were very good, (double cavity mold) so I hope I can get a good batch today or tomorrow.
I am using 30/1 rotometals alloy. I accidentally posted the same photo twice, was having a difficult time getting a photo that clearly showed the damage without getting washed out by the light. 
Thanks!
Joe 

The burrs are not, usually caused by miss handling by the user but, much more likely, caused by a dull cutter when machining the mold.

Have you tried smoking the mould???

I don't cool my molds as once I get a rhythm that works I just keep casting at the same pace. If I have to stop for any reason I leave the last bullet in the mold to retain the heat and then dump it when I restart my casting.

Hello everyone, Thanks for your replies! I was able to cast today and took your advice and brought the  lead temp up to just under 800 deg, mold temp got up to  a little over 300 by the time I quit.
Total cast= 116, Total keepers=92, rejects remelted=7, sighters and practice bullets = 17.
Match grade= Perfect bases, (photo to follow), bands completely and evenly filled out, no flaws except very minor surface imperfections which will be erased when sized. 
Practice and sighters= very minor defects such as tiny dimples or very small areas of imperfect band fill out. 
Issue: toward the end of the session, I started getting some flashing at the mold lines. I am using locking handles to consistent pressure is not the issue. I kept the ones that I could scrape the flash off with my fingernail, now sure how they will shoot, will test ten against some that done have the flashing. 
Weight:  a few were under 320.6 and they went to the sighters, which otherwise we not weighed.
I sorted per .1 grain. Twenty two were between 320.6 and 320.9
Thirty seven were between 321.0 and 321.4
Twenty three were between 321.6 and 321.9
Nine were between 322.0 and 322.3
I had one at 320.3 which went with the sighters because it was quite a bit lighter than the others. 
Conclusions:
1) As the temp of the mold got higher toward the end, and that is when I started getting the flashing. I dont like it because I dont know the extent to which it will  affect the group, will try to do some testing vs Match grade so see if I can notice a difference.
2). Lead temp at or just under 800 deg produced great bullets. My gas valve is quite coarse, have to keep fiddling with it to keep as close to the target temp as possible
3)  I will try to get the mold hotter to start with, but find the sweet spot that produces good bullets without flashing. Something around 300-310 might work
4) Not sure how I should sort them for shooting. Started out years ago sorting to one grain, which might be the most practical. Then I sorted to half grain, and last year .1 gr,. My bench skills are not good enough to be able to detect a difference so far. Obviously, the heaviest bullets   are most likely to have no voids. the question is where to draw the line. Considering that the scale has an accuracy  range of .1 grain, there could be a spread of up to .3 grain, so I am thinking that sorting to less than a half grain is probably not worth the trouble. Would like to hear your views on that one. 
to be continued!
Joe S