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kevin c
10-14-2020, 04:33 PM
I know this depends on what you're willing to accept, and have read the threads where folks describe what they consider fatal flaws. I've also read about the techniques that help keep the unmentionables to a minimum (heck, I've contributed my limited experiences to the piles of recommendations), but what I'm interested in knowing is, when you're in the zone, casting as well as you can, can you realistically expect all or nearly all, not just keepers, but nigh on visually perfect boolits?

I think I've gotten close on occasion, when I'm rested, the weather for my outdoor casting is cooperative, and I run just one or two pots worth of alloy (35 to 40#). Using a preheated 8 cavity aluminum mold and discarding the first one or two pours, I'll keep 98%, with 95% looking very good up to no defects noted. But it's harder the longer I cast, with the cadence, pouring technique getting less consistent with fatigue.

Maybe it doesn't always matter (for instance, I tumble the boolits together in coating them and those perfect edges don't stay that way), but I'd like to know what the acme is.

ascast
10-14-2020, 04:37 PM
i THINK YOUR PERCENTAGES ARE SPOT ON. opps I can cast for about 1 1/2 hours at a fast pace, running at least two molds.

redhawk0
10-14-2020, 04:41 PM
I casted ~600 31141's over the past few days. (two sessions) I had about 70 rejects when I was done. 11-12% for me is in the range...I usually fall between 10-15%. If I'm under that....its been a great casting session.

redhawk

Txcowboy52
10-14-2020, 04:52 PM
I think it varies a lot of things come into play , I would say after about 1 1/2 to 2 hours I need a break . I think hawks average and mine are really close.

Walks
10-14-2020, 04:56 PM
I usually run about 3-4% rejects after the rhythm starts to "flow".

popper
10-14-2020, 05:01 PM
Usually 2-3% and most are my fault.

Kraschenbirn
10-14-2020, 05:08 PM
Cast something like 530-535 Lyman 358477s yesterday morning. Not counting a few culled as they dropped from the mold, I tossed out around 20 this afternoon as I loaded my #5 containers for PC. Bottom line: 514 baked and ready to go though the sizer (approx. 3% reject rate).

Bill

bangerjim
10-14-2020, 05:19 PM
I have found that preheating my molds to FULL CASTING TEMP (not just warming on the side of the pot like I & many used to do) with an electric hotplate gets me an extremely high % of keepers. Usually the 1st drop is almost perfect, but there are always a few clunkers in there over the 1.5+ hours or so I cast. I would say my average, using 4, 5, and 6 cav AL and brass molds, is 1% re-melts. I never run 2 molds at a time. I use the same mold to make a pile of that style, then switch to another mold on the hotplate and cast until I get another pile, and so on. I drop all of them in a 9x12 baking pan filled with water and an old bath towel to stop dropping dings. I just scrape the cooled cast boolits to one side if the pan and go on to the next mold. That allows me to avoid sorting sizes at the end! If it gets too full, I just scoop them out by hand into a container. Any sorting for damage is done after the fact at a later time & date.

poppy42
10-14-2020, 07:55 PM
It really depends on what I’m casting. I am certainly not as discriminate when casting range fotter pistol bullets as I am with rifle bullets. I also find that the bigger the bullet the easier it is to cast. when I cast 22 caliber pills my reject might run 10 or 12% on a bad day.

jimb16
10-14-2020, 08:26 PM
Once the mold is hot and the mix is right my reject rate is no more than 3%. I make up the alloy that I'm going to use ahead of time so I have to flux maybe once or twice per pot. I usually make runs of 4-500 at a time.

Mk42gunner
10-14-2020, 08:32 PM
Like so many things in casting boolits, it depends.

I think one of the main things is having a quality mold, with alloy and temperature of both the alloy and the mold that agree with each other. I'll give a couple of examples:

1. I had a Hensley & Gibbs #256 that the last time I cast with it before I sold it, I ran just under 250 boolits with one failure to fill as the only reject. The reason I sold it is that I don't have a .41 Magnum and really don't see me getting one at this stage in life.

2. The last time I ran my Lee DC 312-185, bolits were raining out of it like it was a H&G. I spent a few hours doing the fill, twist the sprue plate, open the mold and watch the boolits just fall out routine. I still have a couple of inches worth on the bottom of a 3lb coffee can.

I don't know exactly what it takes to enter the zone while casting, but it is very productive when it happens.

Robert

lightman
10-14-2020, 08:49 PM
I really don't know my % of culls but its pretty low. Probably in the 1% range. I preheat on a hot plate and usually cull the first and second mold full and then get good bullets until its time to refill the pot. I'm also pretty picky about my cast so some casters might keep those first ones that I reject. I'll occasionally let the pot linkage slip out of my fingers and get a bad pour but I usually get good bullets after those first couple of pours.

kevin c
10-15-2020, 12:51 AM
Thanks for the replies, folks. Please keep them coming!

How many cavities are you all running? Maybe more opportunity over six or eight cavities to not get the transition to each one just right, compared to a single or double? Maybe more trouble handling a bigger mold, with faster onset of fatigue induced goofs?

charlie b
10-15-2020, 08:29 AM
Depends on the mold and bullet.

Pistol bullets, about 90-95% good (6cavity). 160gn or so .30cal rifle bullets about 70% (4 cavity). 210gn .30cal rifle bullets about 50% (double cavity). And yes, I am really picky about the rifle bullets and that includes ones tossed back because of being outside weight tolerance.

I only cast one mold at a time. More relaxing for me that way and I can go 30-40min between breaks.

Yes, I am not that good at it, but, it suits me. I have plenty of time on my hands so if I have to toss a bunch back in the pot it is no big deal. As long as the rifle bullets shoot better than MOA at several hundred yards I am happy.

rintinglen
10-15-2020, 12:54 PM
Like most of the others here, it varies for me. My pistol boolits run usually 92-98% keepers, my rifle boolits keeper percentages run lower, more like 60-75 for 30 cal, 75-90 for 45-70 and 44. My experience has been the smaller the boolit, the more rejects. However, I have a 456-401 which stands that on its head--60% is a good day for that mother bear.

greenjoytj
10-15-2020, 02:04 PM
I weigh every bullet I cast then set that bullet onto a piece of paper with that weight written on it.
When all the bullets are weighed and each weight counted for quantity I seen a bell curve pattern emerge.
The lightest I cut in half to see why it was so light. The cause is a visually detectable malformation or a void inside.
The very heavy bullets I have no explanation for, I always check the mold for lead keeping the mold open slightly.
I try to keep as many as I can + or - 1 grain selected from either side of the center of the bell curve weight. I don’t know what the percent keepers that would be but I see on some days I get fewer rejects, some days more.

bangerjim
10-15-2020, 02:21 PM
I weigh every bullet I cast then set that bullet onto a piece of paper with that weight written on it.
When all the bullets are weighed and each weight counted for quantity I seen a bell curve pattern emerge.
The lightest I cut in half to see why it was so light. The cause is a visually detectable malformation or a void inside.
The very heavy bullets I have no explanation for, I always check the mold for lead keeping the mold open slightly.
I try to keep as many as I can + or - 1 grain selected from either side of the center of the bell curve weight. I don’t know what the percent keepers that would be but I see on some days I get fewer rejects, some days more.

WOW! That is quite a process. You must be using single cavity molds? I only own ONE single cavity Fe SAECO mold. And never ever any more.

When I cast, I drop 4/5/6 boolits at at time (every 12-14 seconds) from the many multi-cacity molds I own. Fill - drop - repeat.........until I get tired or have enough for that session. Once I am totally done I do a quick inspection and PC them so they are ready to load/shoot. I don't care about weight deviations at all. Only major deformities and voids catch my eye. But all I do is kill lots of water bottles and paper targets! No competition shooting (other than against myself). No killing of animals. Just good old fun plinking.

gwpercle
10-15-2020, 02:21 PM
When me , moulds and metal are all at casting temperature ...hot ... and I've establi9shed a good rhythm ... Nearly All ! ... And I insist on 99% Perfect boolits .
But... I can only do Nearly All Perfect with 2-3-4 cavity mould , Lyman ladle with side dipper and by pressure casting .

Using a bottom pour pot with ... the same moulds = 50% defective and thrown back into the pot.

For me the bottom pour pot gives me a lot of defective boolits ... the dipper , open top pot and pressure casting gives me mostly perfect boolits .
Gary

dverna
10-15-2020, 02:32 PM
I weigh every bullet I cast then set that bullet onto a piece of paper with that weight written on it.
When all the bullets are weighed and each weight counted for quantity I seen a bell curve pattern emerge.
The lightest I cut in half to see why it was so light. The cause is a visually detectable malformation or a void inside.
The very heavy bullets I have no explanation for, I always check the mold for lead keeping the mold open slightly.
I try to keep as many as I can + or - 1 grain selected from either side of the center of the bell curve weight. I don’t know what the percent keepers that would be but I see on some days I get fewer rejects, some days more.

The very heavy bullets are the good ones.... think about it. There is an old saying...you cannot put 10 lbs of manure in a 5 lb bag. Molds are the same. You cannot put 150.5 grains of lead in a 150 gr cavity.

Unless you have a large protrusion where the sprue is, or you did not close the mold completely, it is impossible to put more material into a fixed volume. If you have multiple cavities, some may throw a larger bullet. If using "mystery alloy" and topping off the pot with alloys of different densities that can affect weight.

Try casting 200 bullets without adding any alloy to your pot and shoot a group with the heavy bullets You may be surprised.

W.R.Buchanan
10-15-2020, 05:28 PM
For me it almost entirely depends on the mould itself. With my Mihec Brass Moulds usually the first 1 or 2 drops may have imperfections. Once the mould is the right temp they run perfect for as long As I can stand to do it.

My steel moulds generally work well but they take more time to settle in. Aluminum moulds, some work well some don't and them's that don't,,, get sold! Lee moulds generally work well, and I still have my very first Lee Mould (.429-240GC 1978) and it still drops perfect boolits for my .44's.

I find short fat boolits are easier to get to run than long skinny ones. Those generally need some Tin to fill out right. I cast everything with Wheel Weights cuz I have alot of it.

I had a Lyman 173 gr .358 SWC mould I never got even one decent boolit out of. Somebody else has that now.

I have found that if a mould doesn't work right I will smoke it. if that doesn't work then I find another mould. Not willing to spend the time doing all the little tweaks to get something to run that has an attitude. Next time I pick it up it probably won't work either, but I will have forgotten what made it work last time. Better to just send it down the road.

My .02

Randy

milkman
10-15-2020, 06:49 PM
I have found that the heavy bullets are usually slightly larger in diameter, which may explain why they shoot well. Just my experience

greenjoytj
10-18-2020, 09:09 AM
For me the bottom pour pot gives me a lot of defective boolits ... the dipper , open top pot and pressure casting gives me mostly perfect boolits.
Gary

What is pressure casting?

Cosmic_Charlie
10-18-2020, 09:25 AM
There can be hiccups even when everything is running well. I have reached the point where with a properly pre heated mold I can get good boolits immediately, once I get the rate of pour adjusted.

JoeJames
10-18-2020, 09:32 AM
I have not been casting very long, but I was thinking while casting yesterday that if a beginner asked me which mold to start with, I'd recommend big short boolits like my Lee 430 240 grain. I was grinning like a possum after a very good run with those... better than 90% maybe 95%. And BTW using a ladle. Emboldened by that I got out my double cavity mold for 98 grain 32 caliber swc's ... and was chastened and not near as cocky ... more like 40% culls.

gnappi
10-18-2020, 10:20 AM
The only things I reject are any from a short pour without a base and any with a wrinkle that goes all the way up and down the length of the bullet.

Everything else goes down range. PC covers most sins on the bearing surface and if I get a snotty tip or two I am OK with less than perfect tip

hickfu
10-18-2020, 11:30 AM
My OCD wont let me see a defect and keep it [smilie=b: But I have learned to keep the pot at 720* and turn the stream down so it takes longer to fill the cavities, It cast more consistent and much closer weights that way as it does not trap any air in the mix. Every one of my 9mm bullets (120lbs that I cast the other week) are within 1 grain of each other and probably closer.

Rich/WIS
10-18-2020, 11:36 AM
All my molds are either Lee 6 cavity pistol molds or NOE 5 cavity rifle molds. Preheat with a hot plate and first couple of pours usually reject maybe half or less, after that seldom get a reject.

kevin c
10-18-2020, 02:17 PM
What is pressure casting?

Rather than letting the alloy stream free fall into the cavity, the spout of the ladle or the nozzle of the bottom pour is pressed into the sprue plate opening. That gives increased filling pressure and additionally there's no air cooling of the alloy entering the mold.

JonB_in_Glencoe
10-18-2020, 02:31 PM
Once in the Zone...

a month ago, I cast up some 9mms. about 1000 of them.
Obviously I am not counting the first 10 or 20 pours into this NOE 5 cavity mold.
I visually sorted them as I ran them through the lubesizer, there was 30 that were culled...but honesty, those culls were plenty good enough for pistol boolits. I was quite proud of that, it's usually more like 100 that I'll cull out for that size of a batch.

Aunegl
10-18-2020, 04:52 PM
After a four hour session, 15% are culls.

David2011
10-18-2020, 05:47 PM
Maybe it’s because the majority of my boolits are the short fat (170 gr .40) type my rejection rate is pretty low but no idea of percentage. That’s in spite of using a Lee 6 cavity mold. I also use a hot plate and try to keep a steady pace which is fairly necessary with the Lee six bangers. For me it’s kind of a dance between keeping the mold temperature good and keeping the spout from freezing.

Using iron or steel molds the rejection rate is very low once everything is up to temperature, regardless of the boolit shape. I only cast for handguns for now so no long skinny boolits. I’ll eventually cast for .375 H&H. Long but not skinny.

kevin c
10-19-2020, 02:48 AM
Soooo...high BC rifle boolits (long and skinny) are technically more difficult to cast well, or is it more that fewer defects are accepted, leading to a higher reject rate despite the same percentage of flaws in the same number of pistol boolits? Could it be # of cavities or mold material?

charlie b
10-19-2020, 09:53 PM
I think it is both. They are difficult to cast well, and, I want fewer defects in those bullets.

My theory on the difficulty is the temperature differential in the mold. The relatively thin bullet is affected by a mold that is different temperatures over the length of the bullet cavity.

rintinglen
10-20-2020, 12:07 PM
I’m riding with Charlie B. On this one. Long skinny Boolits are harder to cast well, and the degree of perfection required to shoot a 2 inch 100 yard group is proportionally much greater than that required to shoot a 2” group at 15 yards. While I can’t specifically pin exactly why it is so, a 311-467 will more likely have rounded edges, wrinkles, and other defects than a 311-465, which is about 40 grains lighter. Charlie’s theory makes sense to me.

charlie b
10-20-2020, 05:49 PM
Yes, my pistol bullets I accept a lot of minor flaws, but, none in the base. Fist size group at 25yd is fine. I usually do not even shoot groups, just 6" steel plates. OTOH, I am not happy with my cast rifle bullets unless they shoot 2" or better at 200yd.

McFred
10-24-2020, 12:58 PM
I cast 622 "keepers" yesterday, I rejected 15 other projectiles. 25 of the keepers I set aside as they'd be fine for pistols, but I'd hesitate for longer range carbine use. That's less than 2.5% reject. I qualify that percentage, since as I cast, I toss sprues and obviously bad projectiles back in the pot.

https://i.postimg.cc/sXK3CjcZ/CastDay2.jpg

Hanzy4200
10-25-2020, 05:57 PM
For me it all depends on the mold. I have well behaved molds that give 98% keepers, and I have PITA molds that might squeeze out 80%.

Shiloh
10-27-2020, 08:21 PM
I'm a lot more picky about rifle boolits.

Shiloh

fredj338
10-30-2020, 02:00 PM
I probably run a 2-3% reject rate but I may be more picky than some.

ACC
10-30-2020, 10:46 PM
I usually have 10 to 15% rejects.

ACC