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aussie460mag
10-14-2011, 05:29 PM
Hi, just want to get your opinions on the craters i seen to be creating.

UtopiaTexasG19
10-14-2011, 05:54 PM
I will be curious to what others say about your pictures. In my case when I cut the sprue too soon and because my mold is too hot the base of the bullets have a "smeared" look as the lead is still too soft/hot and does not shear off with a clean cut.

mdr8088
10-14-2011, 05:54 PM
Are you overflowing your sprue plate? The lead contracts as it cools and pulls some down into the mold. I'm guessing it's a combination of this and not hot enough. A mold temp of 420 to 440 degrees will give you the most uniform bullets. It's normal to have a mark there, not the indentions though. Maybe hotter mold, overflow the sprueplate and let if frost over plus a second or two. You'll get a feel for how it's easy to open when hot. If you wait that second to long you'll notice it feels different. To quick and you'll smear the top.

mooman76
10-14-2011, 06:12 PM
Looks like you are correct in thinking you are getting craters from cutting too soon. You need to wait about 2 seconds longer. The lead is only partially solidified and the sprue is pulling a small amount of lead out as it cuts.

Blammer
10-14-2011, 06:12 PM
looks to me like you're cutting it too soon, let it cool a bit and if those are not BB boolits you need to increase your pour speed or do something to help fill out the base edge.

OnHoPr
10-14-2011, 06:38 PM
I use to cast boolits when I was a teen for a local gunshop. We used Pb and cast all the way up to .72cal without any problems using cast iron molds. I don't have any problems with my Lee .44 310gr mold. But, I'm having the same problem with a .501 440gr Lee. That boolit that you are casting and the .501 are big diameter boolits. The sprue seems to be cooling before the core which the molten alloy can't shrink back into the mold because it has solidified already. I've put more tin in my alloy, made sure the mold was hot, change casting temperatures, waited until I knew the whole cast was solid and I'm still tinkering with the problem. I haven't tried pure Pb though because I want a hard bullet. I'm not sure, but it seems that you have a good radius on the base there, mold or alloy not hot enough, not enough tin, pore is not fast enough, I'm not sure. I hope one of the boolit master gurus could answer your OP because I'm having the same difficulties.

Lizard333
10-14-2011, 06:40 PM
Try a hotter mold and a larger sprue. If you were cutting it too soon, you get smearing not pitting. Let us know.

Tatume
10-14-2011, 07:05 PM
Those bullets don't have enough lead on top of the sprue plate. As they cool they are pulling lead down the sprue hole, and there's not enough to keep up with the internal shrinkage. I've seen it many times. It is not related to cutting the sprue too soon.

The cure is to keep pouring lead and overflowing for awhile while the interior of the mold begins to cool. If you are using a ladle, keep pouring until the ladle is empty, and let the overflow go back into your pot. If using a bottom-pour pot, pour for several seconds after the mold is full, and catch the overflow in an ingot mold.

DLCTEX
10-14-2011, 07:06 PM
Cutting too soon will cause the crater, seems to be more likely to happen with large boolits. May also need to sharpen the cutter. It can also occur when pressure casting and the alloy hardens as the mould is pulled away.

aussie460mag
10-14-2011, 07:18 PM
Thanks for the info, I am casting a lee 6 cav 300gr gc, out of a lee 10lb pot, I have tried waiting longer before cutting and this is still what i got.

I think i'm leaning towards my sprue plate is too cool compared to the mold and setting the puddle too quickly.

Tazman1602
10-14-2011, 07:47 PM
Just out of curiosity are you pouring a good, healthy sprue plate full?

Wayne Smith
10-14-2011, 08:18 PM
Cutting too soon with a high antimony mix will give you the craters rather than a smear. A high Pb mix will give you a smear. I'll bet that mix was pure clip on ww.

aussie460mag
10-14-2011, 08:42 PM
Yes I fill the sprue plate full, the alloy is clip on WW with a little solder added to bring it up too 2% tin

williamwaco
10-14-2011, 09:30 PM
I would like to see some better photos of some side views of those bullets.

When I expand them, it appears that the driving bands are seriously rounded. This could be caused by lead or mold too cold or by mold too hot and severe frosting. either way, I suspect you have bigger problems than just cutting the sprue too soon ( although I am 90% sure you are cutting it too soon )

Next time you cast. wait for the sprue to completely frost over, then tap it with the edge of your stirring spoon or your cutoff stick. If it is still soft wait until it does not deform when you tap it. ( tap - not WHACK ) Then cut the sprue, I expect you will not have the cavities.

BABore
10-14-2011, 09:53 PM
There's nothing wrong with tearing a bit of the base out if done consistently and your getting good, complete fillout. It has not affected my accuracy in the least and I've compared many groups. IMO you will get more consistent boolits because your keeping the blocks and sprue plate at a hotter condition. Cast to a timed cadence once perfect fillout is attained and use a fan to cool the SP, then empty mold to keep the mold temp in the zone. Fast cooling (wet rag) of the SP may allow you to get more boolits per hour, but it can cause wild temperature flucuations at the boolit's base when poured again. You'll typically get higher weight varance and a greater possibility of air pockets near the base. This doesn't mean tearing out a huge pocket by any means. Just a small amount from the boolit's center.

The bases of your pictured boolits are very similiar to what I normally get when I'm running a steady, hot pace. BP lube will take care of smearing of the SP. Just work on getting the fillout better for a nice square base.

Char-Gar
10-14-2011, 11:42 PM
Yes, you have wet sprues! You are casting to fast. The best way to avoid this I know, is what Bruce B taught us some years back.

Take a folded cloth and place it in a dish with a little water, so the water will wick into the cloth. Fill your mold and invert it onto the damp cloth. The sprue will harden in just a second or two and then you can cut it and their will be no torn bases.

Be certain and pour a generous sprue, so when the metal contracts when cooled, there is not a hole in the base.

You will get better bullets and cast faster this way. There really is not great problem in casting good bullets. It is a pretty simple thing.

geargnasher
10-15-2011, 01:48 AM
There's nothing wrong with tearing a bit of the base out if done consistently and your getting good, complete fillout. It has not affected my accuracy in the least and I've compared many groups. IMO you will get more consistent boolits because your keeping the blocks and sprue plate at a hotter condition. Cast to a timed cadence once perfect fillout is attained and use a fan to cool the SP, then empty mold to keep the mold temp in the zone. Fast cooling (wet rag) of the SP may allow you to get more boolits per hour, but it can cause wild temperature flucuations at the boolit's base when poured again. You'll typically get higher weight varance and a greater possibility of air pockets near the base. This doesn't mean tearing out a huge pocket by any means. Just a small amount from the boolit's center.

The bases of your pictured boolits are very similiar to what I normally get when I'm running a steady, hot pace. BP lube will take care of smearing of the SP. Just work on getting the fillout better for a nice square base.

FINALLY! I was hoping someone would point out that there isn't anything at all wrong with those little craters (or goat-arses as some of us call them), and in fact in many instances they make it much easier to tell by inspection that your boolits were cast, cut, and dropped in a very consistent manner, and the temper of your boolits will likely be very uniform.

I learned when water-quenching boolits that they need to get right out of the mould and into the water pronto to achieve the hardness I wanted with diluted WW alloy, and that meant cutting the sprues while still in the mush phase, just firm enough to not smear lead on the blocks, but still soft enough to cut with a single gloved finger. There is a very narrow window in which to cut the sprue this way, usually about one second. Then straight to the quench bucket they go. Any boolits that get stuck or are delayed more than two seconds getting into the water after opening the mould are diverted to the cull pile. Consistent craters and consistent timing from the pour to the water make really good boolits.

It does appear that the bases are rounded, might check the sprue plate to see if it's too tight, or maybe pour a faster stream into the mould. I get rounded bases but otherwise perfect fillout on .45 moulds when I'm getting to the last 1/4 of my 20-lb bottom-pour pot, the loss of head pressure reduces the stream volume considerably even with my pintle adjusted to wide-open, and if the lead pours in below a certain rate the bases will be perfectly rounded on the edges just like all the ones in your pic.

Enlarging the sprue holes can help some, as can pouring a larger sprue puddle to heat the plate, but even if you do all that and have plenty of tin in there and good venting, the bases STILL won't be sharp if the lead isn't filling the mould quickly enough.

Gear

BABore
10-15-2011, 06:03 AM
FINALLY! I was hoping someone would point out that there isn't anything at all wrong with those little craters (or goat-arses as some of us call them), and in fact in many instances they make it much easier to tell by inspection that your boolits were cast, cut, and dropped in a very consistent manner, and the temper of your boolits will likely be very uniform.

I learned when water-quenching boolits that they need to get right out of the mould and into the water pronto to achieve the hardness I wanted with diluted WW alloy, and that meant cutting the sprues while still in the mush phase, just firm enough to not smear lead on the blocks, but still soft enough to cut with a single gloved finger. There is a very narrow window in which to cut the sprue this way, usually about one second. Then straight to the quench bucket they go. Any boolits that get stuck or are delayed more than two seconds getting into the water after opening the mould are diverted to the cull pile. Consistent craters and consistent timing from the pour to the water make really good boolits.

It does appear that the bases are rounded, might check the sprue plate to see if it's too tight, or maybe pour a faster stream into the mould. I get rounded bases but otherwise perfect fillout on .45 moulds when I'm getting to the last 1/4 of my 20-lb bottom-pour pot, the loss of head pressure reduces the stream volume considerably even with my pintle adjusted to wide-open, and if the lead pours in below a certain rate the bases will be perfectly rounded on the edges just like all the ones in your pic.

Enlarging the sprue holes can help some, as can pouring a larger sprue puddle to heat the plate, but even if you do all that and have plenty of tin in there and good venting, the bases STILL won't be sharp if the lead isn't filling the mould quickly enough.

Gear

Exactly!

That's why so many get a difference in hardness between water dropped and oven heat treating with the same alloy. Too much mucking around waiting on a shiny cut sprue and the boolit temp went below the proper threshold to fully heat treat.

On a GC boolit, you can also get a slight bump on the boolit base when trying to acheive a clean cut. A slightly loose sprue plate and a poorly angled hit to the sprue plate will raise a hump as it's cut. It is then possible to seat a GC slightly out of square if not enough pressure is used against the base. Like when using a nose first push-through die alone.

I hand cut all of my sprues with a gloved hand. 4 and 6 cavity molds (BRP) are not a problem if done at the proper time. Less mold wear and smoother cuts.

LongPoint
10-15-2011, 06:05 AM
Also, check the cutting surface of the sprue plate holes to make sure they are sharp. I bought an older Lyman mold from a board member a while back and it looked like the machining tools were stopped about .050 short so a square cutting edge was left. Board member "Ben" did a nice write-up on this a while back.

Since I started using Bullplate I cut the sprue while they are still jiggly and get really nice bases.

Good luck, LongPoint

ku4hx
10-15-2011, 06:14 AM
Hi, just want to get your opinions on the craters i seen to be creating.

Try waiting a ten-count longer and see what happens. Then maybe a fifteen or twenty-count.

adrians
10-15-2011, 09:02 AM
you may have a small burr on the sprue hole face which along with cutting too soon it may be dragging the lead out a tad.
are you getting an arc line on the mold block top when sprue is cut?
if not then all of the above answeres will cure your small problem .
just a thought.:twisted::popcorn::evil:
have a good sprue pool and wait or count to ten,
some old guy told me that he blows a full lung full of air on his pool till it frosts and then cuts it, but he is a little eccentric but a 100% good guy,,,[smilie=p:

44man
10-15-2011, 09:12 AM
When I first start, I get a clean cut but as the mold gets hotter, I also get the divots, not as pronounced as shown in the picture.
It is 100% true that they don't hurt a thing with a PB and do make a GC fit flatter. I hate bumps on GC bases, I would rather have a small hole.
I use hard stainless for my plates and get them razor sharp, still will make small divots.
I don't see that as too small a sprue either. I hold the ladle on long enough to have the cooling boolit pull molten lead from the ladle, not the sprue. My sprue will not shrink a depression in the center because the boolit does not need more lead. That is the secret to a filled boolit.
My bases are so sharp that when I wipe lube from the base on a rag, the edges will cut the rag.
I agree with Babore and Gear. All the groups I ever posted, even the crazy 1/4" to 5/16", five shot groups at 50 yards were shot with divots. I can't find a single perfect base on any of my boolits, all have a divot.
Molds really do have an "ignore" feature! [smilie=l:

geargnasher
10-15-2011, 12:02 PM
you may have a small burr on the sprue hole face which along with cutting too soon it may be dragging the lead out a tad.
are you getting an arc line on the mold block top when sprue is cut?
if not then all of the above answeres will cure your small problem .
just a thought.:twisted::popcorn::evil:
have a good sprue pool and wait or count to ten,
some old guy told me that he blows a full lung full of air on his pool till it frosts and then cuts it, but he is a little eccentric but a 100% good guy,,,[smilie=p:

When I get boolits that look like the ones in the OP's picture, it isn't to dragging the lead out as the sprue is cut, it's due to contraction as the lead continues to cool after the sprue is cut, it's a matter of temperature and timing. The base will appear perfect when first cut, but within a few seconds it will begin to suck in as the metal cools more and contracts. Continuing to flood the sprue plate with hot lead for a few seconds after the fill and then waiting to cut until the sprue is fully hardened will prevent the puckers, but a) it wastes time, b) exposes extra alloy to oxidation, c) increases sprue plate wear, and d) does not improve the way the boolits shoot.

Gear

theperfessor
10-15-2011, 12:37 PM
I might point out that ALL ductile metals will exhibit tearing when they are sheared if they are more than a certain thickness. I've seen enough punched and sheared steel plates to understand this. Some factors minimize this tendency, some increase it, but it's always there.

My opinion of the OPs bullets doesnt mean squat. What does his gun tell him?

BossHoss
10-15-2011, 03:23 PM
Off Topic,

But, may I say this is one interesting thread, and I am comparing my recent experiences and getting quite an education.

Thank you , all.

Enough **** kissing, I going to heat up the pot...with the notebook tagging along.

Marlin Junky
10-15-2011, 03:43 PM
The divots are normal for a mold that's up to temp. Base fillout needs to be accomplished by either mold venting, more fluid pressure, or a combination thereof. A couple small aluminum tape shims in the corner of one mold block half at the top near the sprue plate will aid in mold venting if you don't mind casting boolits out of round near the base by about .001". Loosening your sprue plate can help venting as well as beveling the top edge of the mold blocks slightly. More fluid pressure is accomplished by speeding up and or lengthening the melt stream from the source into the mold. Try a Rowell#2 ladle.

MJ

BABore
10-15-2011, 04:35 PM
I might point out that ALL ductile metals will exhibit tearing when they are sheared if they are more than a certain thickness. I've seen enough punched and sheared steel plates to understand this. Some factors minimize this tendency, some increase it, but it's always there.

My opinion of the OPs bullets doesnt mean squat. What does his gun tell him?

Nearly pure to pure lead does not tear out like alloy. Always a shiny cut.

462
10-15-2011, 06:27 PM
Bull Plate allows the sprue to be cut quicker, and without smearing.

Beau Cassidy
10-15-2011, 10:19 PM
When the sprue starts to harden flip the mold over and finish cooling it on a wet towel. Let it sizzle a few seconds. Problem solved. Nice smooth bases. That is how I do it.

geargnasher
10-15-2011, 10:48 PM
I might point out that ALL ductile metals will exhibit tearing when they are sheared if they are more than a certain thickness. I've seen enough punched and sheared steel plates to understand this. Some factors minimize this tendency, some increase it, but it's always there.

My opinion of the OPs bullets doesnt mean squat. What does his gun tell him?

I could be wrong because I didn't cast them myself, but based on appearance I'd put money on those craters being formed by alloy shrinkage AFTER the sprue was cut. Antimonial alloys form more structured dentrites when cooling than pure lead. Pure lead is "eutectic" (obviously) so it freezes uniformly throughout and doesn't have a tendency to form large, lattice-like crystalline structures when cooling. Or actually, pure lead DOES form large dentrites, but it all gets solid at the same time and shrinks uniformly rather than "flowing" in certain areas like where the very last part of the alloy to cool, the middle of the base, creating craters like alloyed lead can. That's why pure lead boolits are always shiny, no matter the mould temperature.

Since WW metal has a fairly long mush phase in between the primary and secondary fields of solidification, and with any ternary lead/antimony/tin alloy where the concentration of antimony is less than 11% AND tin less than 5% lead is the metal on the primary phase of solidification, and furthermore lead forms the largest dentrites of the three when cooling, it follows that WW metal will have large lead dentrite formations filled in later with Sb/Sn and free Sb as those two solidify within the canopies of the lead "trees". As the Sb/Sn and Sb cool and solidify within the already solidified lead structure, they shrink and reveal the dentrites. This is why the puckered craters form on the boolit bases after cooling for a minute or two when sprues are cut "too soon", and why WW metal (among many other lead alloys) has a long mush phase with grainy consistency, and why the surface of free WW metal (not contained within the smooth surface of a mould) will be dull and crystalline-looking.

It's possible, under certain conditions, to "tear out" the boolit base when cutting the sprue, but usually the sprue plate has to be pretty loose for that to happen. If the sprue tears out the bottom of the boolit and carries it with the plate, it usually smears the torn-out lead on the block as it drags across while opening.

Gear

Down South
10-15-2011, 11:46 PM
Looks like a cold mould and cutting the sprue too soon to me from the pic you posted. The rounded base is from a cold mould.

44man
10-16-2011, 09:31 AM
I have to go with Gear here. The metal is still too hot to form together and fractures. I get no smears from that though.
If I let the sprue harden a little longer, they get harder to cut so it takes a few short taps with my stick but then the cut will be clean with no tear out.
I have never gone back to the glove thing because I get more smears on the top of the blocks and on the plate. Even BP will run out fast and to tell the truth it makes a fine tinning flux.
Nothing to speed casting is really worth the work. Cooling the plate on a rag can get so touchy the next boolit might not fill.
A nice even pace can provide 100 perfect boolits without ever having to stop and fix something. Fooling with speed might give you 150 boolits with 50 rejects.
Casting right is a relaxed process with no fussing, fixing, cleaning, making a mess or getting frantic. It is really boring, nothing more then a steady pace and repetition sort of like driving screws in drywall or sizing 1000 pieces of brass.
The only repetition worth a hoot is bending my elbow with a good beer! [smilie=w:

OnHoPr
10-16-2011, 10:05 AM
44man

What about pulling the trigger? Is there a beer poll on this forum?:-):Fire:

wallenba
10-16-2011, 10:18 AM
Cutting very early causes smearing. Cutting just before it is ready (still too soon) results in what you have, it tears it out of the base, and the crater deepens even more as it cools and draws down. If you are unsure, press down on the sprue with something like your tapping stick to see if it has some 'give'.

geargnasher
10-16-2011, 11:42 AM
I have to go with Gear here. The metal is still too hot to form together and fractures. I get no smears from that though.
If I let the sprue harden a little longer, they get harder to cut so it takes a few short taps with my stick but then the cut will be clean with no tear out.
I have never gone back to the glove thing because I get more smears on the top of the blocks and on the plate. Even BP will run out fast and to tell the truth it makes a fine tinning flux.
Nothing to speed casting is really worth the work. Cooling the plate on a rag can get so touchy the next boolit might not fill.
A nice even pace can provide 100 perfect boolits without ever having to stop and fix something. Fooling with speed might give you 150 boolits with 50 rejects.
Casting right is a relaxed process with no fussing, fixing, cleaning, making a mess or getting frantic. It is really boring, nothing more then a steady pace and repetition sort of like driving screws in drywall or sizing 1000 pieces of brass.
The only repetition worth a hoot is bending my elbow with a good beer! [smilie=w:

Not true, not true!! Bending one's finger to squeeze the trigger is worthwhile repetition too! :Fire:

Gear

W.R.Buchanan
10-16-2011, 12:32 PM
You can cut the sprue too soon and that casues the problem shown in the picture. You can't cut the sprue too late. It takes 20-30 seconds for the lead to solidify completely on a hot mould.

I have been filling both cavities on my moulds (the one closest first) and then leaving a substantial gob on the top covering both holes. This results in full pours everytime with complete mould fillout and perfectly sharp driving bands. This and preheating the moulds to "real hot" on the hot plate, have been the two single technique changes I've done that have resulted in perfect boolits in every session with almost no startup pours wasted.

I pour the closest cavity first as you have a tendency to have the handles lower than the mould, and then go to the second and then keep dumping lead until both are covered, and lead runs off the inside edge of the mould.

The hot mould keeps the lead molten longer and the overfilled sprue keeps head pressure on the mould cavity until it's completely filled. Understanding these two functions is IMHO the key to perfect pours, and once you see it work for yourself, you'll be able to run any mould to perfectiuon.

I did 215 RCBS .45-330FNGC boolits in one run last week and lost 3 to incomplete fills.

Also another thing I noticed is when you get a complete fill on the mould the sprue plate will be pushed away from the top of the mould blocks as the lead expands into the mould. This results in a slightly convex surface on the bottom of the Boolit about .002 proud. Incomplete fills do not do this.

Lead smears on top of the mould blocks and bottom of sprue plate need to be removed immediately and a SS wire tooth brush works well for this. Using some kind of lube on the sprue plate helps keep this to a minimum, but just letting the mould cool a little longer is the real cure.

44man is right about the pace of the casting session I have heard that some listen to books on tape when making boolits. I sing to myself to keep the rythym going.

Randy

44man
10-17-2011, 08:54 AM
Gear, pulling the trigger is good too but I run out too soon and then it is back to casting and loading so sometimes it is better to stare at my loads while I bend my elbow. :bigsmyl2::bigsmyl2:
I ran out last deer season and had 5, .44's left. I killed 3 more deer and had 2 shots left! [smilie=s:
Now I found something that works for a smear if not too thick.
I keep wood matches handy and light one, blow it out right fast. Rub the head on the smear and it will remove the lead. It might take 2 matches but it does not scratch anything and seems to add some carbon to the surfaces. I don't know why it works so well but have been doing it over 50 years. I don't remember how I first tried it either, too stinking old! :veryconfu

cbrick
10-17-2011, 09:34 AM
Looks like a cold mould and cutting the sprue too soon to me from the pic you posted. The rounded base is from a cold mould.

Looking at the OP's photo it could well be a cold mold but it is very possible to have the mold up to temp and the sprue plate too cold. A cold sprue plate will give rounded bases like that, the cure is a larger sprue puddle to heat the plate.


Lead smears on top of the mould blocks and bottom of sprue plate need to be removed immediately and a SS wire tooth brush works well for this. Randy

A stainless steel brush? Maybe, possibly and very carefully on an iron mold or sprue plate but positively, absolutely never on or even near an aluminum or brass mold.

Rick

44man
10-17-2011, 11:09 AM
Looking at the OP's photo it could well be a cold mold but it is very possible to have the mold up to temp and the sprue plate too cold. A cold sprue plate will give rounded bases like that, the cure is a larger sprue puddle to heat the plate.



A stainless steel brush? Maybe, possibly and very carefully on an iron mold or sprue plate but positively, absolutely never on or even near an aluminum or brass mold.

Rick
I like the way you put that. Why damage a mold? No knives or sandpaper, or any other thing that is harsh. Funny how just a match head will work.
I have heard of guys heating the mold so hot they can wipe it clean but then it will be too hot until it cools down.
Maybe it is better to time so no smears happen at all. I just can't see cutting molten lead just to make 2 more boolits. Why has speed casting ever appeared? It is a silly, unproductive waste of time.
Cast an engine block with cast iron or aluminum and dump the mold right away. I want the boolit casters to say they want that bock in their car. :kidding:
Pushing the plate open with a gloved hand means the lead is soft, almost molten. Smears and pushing soft boolits sideways in the mold does not make progress or good shooting. The plate was made to "cut" sprues after the boolit is hard.
Sounds like my wife using my razor sharp chisel for a screw driver. Holy ****, did I go off on her! [smilie=1:

gwilliams2
10-21-2011, 10:50 PM
Try waiting a ten-count longer and see what happens. Then maybe a fifteen or twenty-count.

I've broken a sprue cutter by waiting too long...

W.R.Buchanan
10-22-2011, 03:17 PM
Rick I did indeed mean Iron mould and should have stated so. My Bad!

The wire tooth brushes are very fine and leave a nice smooth finish on the mould blocks. However using ANYTHING abrasive around the mould cavities has to be done with the utmost discression. It takes very little contact with the edges of a mould cavity to ruin it permanently.

Using even a very fine wire brush on the inside or top of a Aluminum or Brass mould would defiately ruin it in short order.

I tend to think of using certain tools in the context of the Machinsit/Toolmaker who would see problems as they arise and would know when to quit. Others may not have this level of experience.

Randy

Crash_Corrigan
10-22-2011, 04:37 PM
First off I dip the mold into the alloy in the pot for a minute or two. This gets the mold and sprue plate really hot. If using a 6 banger I fill only one cavity at first to see how hard the sprue is to cut.

If all is well then I add one cavity at a time until I can easily cut the sprue after I see the small dimple appear in the sprue puddle. Once that dimple appears I know it is time to cut the sprue. No matter if the sprue puddle frosts over or it is still really shiny....it is time to cut.

I use Bull Shops Bull Plate Lube on the top of mold and the underside of the sprue plate and on the alighnment pins so I am not worried about smears on top of the mold. If the sprue just about falls down if I turn the mold sideways then I know I need to let it cool a second or two more. If it gets really hard to cut the sprue then I know it has cooled down too long.

Somewhere in there resides a certain resistance to cutting the sprue that is just right. Not too easy and not too hard. After a dozen or so casts I find that point and coincedently that point also causes the boolits to fall like rain from the mold into a 5 gallon bucket of cold water.

This is the zone. If a boolit gets stuck in the mold and requires assistance to get it out then that boolit goes into the sprues that are cooling off in a metal container next to the lead furnace. Letting it lose too much heat whilst stuck in the mold will lead to different level of hardness in the boolit.

This is not so important with a slow moving .45 ACP or .45 Colt but will affect a faster moving 9 MM, .41 Mag, 327 Fed or a fast stepping .44 boolit.

As far as the divots in the bases go I usually find some kind of mark where the sprue has been cut but not as deep as the ones depicted in the photos of the OP.

I find casting boolits very relaxing and it gives me the feeling of making something with my hands that is useful. I enjoy all aspects of the shooting sports except loading and unloading all my gear into and out of my vehicle.

Since I downsized from a Ford F 150 to '90 Honda Accord Sedan it has become a real chore. When this Honda is replaced I will probably go back to a small PU truck with 4 x 4 drive as I still enjoy getting out into the desert to find solitude.