Cast bullet reject rate

BJung · May 31, 2020, 08:50 AM

What is your cast bullet reject rate?

I'm new to casting and am using Lee Molds. If my cast bullets have folds, cracks or whatever you call them in the bands, I toss them into the pot. If those imperfections are slight, I'll save them into B Grade lot.

Right now I'm re-melting maybe 5-10 percent. My B Grade pile is like 35-40 percent. However my .38 LHP casts are higher. I recently discovered to gently tap the dies from under to align them.

pete2 · May 31, 2020, 09:22 AM

I cast bullets for many years, once the mold comes up to temp you should get good bullets with very few rejects. The bullet alloy makes a big difference, I had to add a little tin to wheel weights to get good castings. Lino makes good hard bullets if you can get it. I used mostly cast iron molds but I do have a Lee one holer that as I recall works well. The molds can become too hot and cause frosted bullets, you can wait till they cool off a little, I actually used as many as 3 2 hole molds at the same time and kept them from overheating.

**Unclenick** · May 31, 2020, 09:32 AM

Burbank-jung,

I've moved your thread to the Bullet Casting sub-forum for you. Here's how you get here to post cast bullet-related questions:

reddog81 · May 31, 2020, 10:38 AM

Once the mold is up to temperature my reject rate is maybe 5% at most. I preheat the mold and then toss the first couple of pours back. Once the wrinkles are gone and the rear driving band is getting complete fill out I start cranking them out and just pay attention to the bullet bases as I open the sprue plate.

Usually upping the temperature a bit will help get better fill. If that doesn't work I'll add a little tin.

USSR · May 31, 2020, 06:30 PM

Quote:

What is your cast bullet reject rate?

Too many variables to give you a straight answer. First, molds are like children; no 2 are the same. Some cast with ease, others are just plain temperamental. Then there is what alloy are you using. Ever wonder why the commercial casters all use a hard alloy? One reason is the bullets tend to drop from the mold looking nice. I cast a lot of hollowpoints, so I use a much softer alloy. This, and dealing with the hollowpoint pins, adds a couple more things where something can go wrong. Oh, and then there is the "Am I having a good casting session" factor. In any case I don't worry about the reject rate. The rejects get remelted, so nothing is lost.

Don

BJung · June 1, 2020, 01:46 AM

Are wrinkled bullets rejected? I separated and used these to practice my powder coating today. Most will return to the pot. As for the rest, will the pistol bullets go straight?

BJung · June 1, 2020, 01:48 AM

Thanks for transferring my post Uncle Nick

USSR · June 1, 2020, 07:58 AM

I reject wrinkled bullets, bullets with a bad base or poorly filled out base, and bullets with poorly filled out driving bands.

Don

BJung · June 1, 2020, 09:48 AM

I'd reject bullets that have wrinkles at the base because the pressure would be applied differently. On all bands, gases will pass through. But what about wrinkles in some bands or on the front?

reddog81 · June 1, 2020, 10:10 AM

I keep ones with "small" wrinkles that are not on the base. Unless you're going for sub 2" groups at 25 yards you'll never notice the difference. If your shooting for 2" groups at 25 yards I'd separate out the best of the best and go from there.

FrankenMauser · June 1, 2020, 12:55 PM

The larger the run, the lower the reject rate.
Less than 50 bullets might have a 50% reject rate - poor fill-out, wrinkles, and even voids - usually from trying to get some heat into the mold.
But if I run a few hundred of something, there usually aren't many rejects once the mold is up to temp and I've got my rhythm.

Most of my bullets are intended for more than just plinking or casual shooting at short range. So, my standards may be a bit higher than average.
Except for pressure test loads, and a few specialized applications, I don't allow any wrinkles.

BJung · June 1, 2020, 01:21 PM

I would guess that pc would fill wrinkles better than traditional lubing. Or, is there a weight or distortion of the bullet under pressure issue?

pete2 · June 1, 2020, 08:56 PM

I would reject all with visible defects. The more uniform the bullets the more accurate they are. You can take it a little further and weigh them after you cull the visible defects, I used to weigh round balls and reject the light ones. It just depends on how critical you want to be on accuracy.

BJung · June 2, 2020, 12:09 AM

Casting bullets is really time consuming right now. Part of it is a learning curve, I'm sure. The best thing going for me now is that I'm practicing powder coating the wrinkled bullets and they're just going back into the pot. By the time my powder paint skills are developed, my casting skills will improve as well. I haven't weighed bullets yet as I am also not ladling lead into my molds but just pouring them from the bottom of the pot to the mold. This must effect the weight but I don't care at this point in time. I have other issues like wrinkled bullets do deal with.

USSR · June 2, 2020, 06:53 AM

burbank_jung,

How are you preheating your mold? If you do it right and bring up to casting temperature, you won't have very many wrinkled bullets.

Don

**Unclenick** · June 2, 2020, 07:13 AM

For accuracy, wrinkles tend not to be evenly distributed around the bullet, putting its center of gravity off-center in the bore. That causes it to be flung away from the mean trajectory path at the exit from the muzzle, widening groups by drifting away from the center. Whether you have enough range and enough velocity in the drift away from the center to matter, depends on range, as suggested previously. But I have seen off-center bullet CG cause ten-shot .45 Auto target load groups sandbagged at 25 yards open from around an inch and three-eighths to about two inches. In that case, it was not wrinkles, but soft, short 185-grain swaged SWC's entering the throat slightly cocked that was causing the off-bore axis CG, and straightening their seating in the cases and going to headspacing on the bullet tightened things up. But that gives you some sense of the effect.

Symmetrical bullet bases are the most important single thing. If those get off-axis or deformed, the uneven play of muzzle blast gasses off the base of the bullet pushing it laterally away from the bore axis and it can introduce a surprising amount of initial yaw. The last thing is the reason asymmetrical muzzle crowns open groups up. There is an element of randomness to the exact effect of the gases, and in one case I saw it lead to keyholing, and random scatter.

Mind you, over a short enough range, even keyholing isn't a problem. Back when silenced .22's were considered the mark of the professional hitman, guns for that purpose would have the rifling reamed out to prevent ballistic matches from being made to recovered bullets (though you would think being caught with such a weapon would give the police a strong clue as to their suspect's occupation). Since the shots were fired at very close range, it made no practical difference. Hatcher even mentions the stopping power advantage of keyholing bullets. So everything depends on what your purposes are.

BJung · June 2, 2020, 08:27 AM

I preheat my molds now by inserting one edge into the molten lead. When casting, I rotate between two double cavity molds. Between the time I'm releasing bullets or refilling the lead, the other mold is resting on the aluminum plate under the pot.

USSR · June 2, 2020, 08:36 AM

Preheating your mold by simply putting an edge into the lead is not enough. Here is how I do it. I have a cast iron 6" skillet that I turn upside down and put on the stove burner. I then put the burner on it's lower setting and place the mold on the skillet for about 15 - 20 minutes which brings the mold up to casting temperature with few if any wrinkles. I cast with brass molds, so since you are using aluminum, alter accordingly. Hope that helps.

Don

BJung · June 2, 2020, 09:14 PM

The skillet idea will work. How about if I just take a propane torch to the mold and move the flame around?

USSR · June 3, 2020, 06:53 AM

That won't get you the slow and steady build up in heat that you want.

Don

big al hunter · June 3, 2020, 07:52 AM

Quote:

. I rotate between two double cavity molds. Between the time I'm releasing bullets or refilling the lead, the other mold is resting on the aluminum plate under the pot.

I use aluminum molds. I preheat them by resting the mold on the top edge of the melting pot. It heats up with the lead. When the lead is ready, so is the mold.

Something to remember with aluminum. It dissipates heat very quickly. And if you place something on aluminum it transfers heat from that item very rapidly compared to other materials. By placing your hot mold on the cold aluminum base plate your mold is cooling more than you would think. Steel and brass molds tend to heat up slowly, but they cool slowly too, so you might need that time using 2 molds to be efficient.

Try running one mold at a time. As soon as the lead gets hard on the sprue, empty the mold and refill it immediately. The mold will not cool as much, and you don't get wrinkles near as often. When I keep that pace I only have to reject the first 2 or 3 casts. Sometimes only the first one.

The size of the bullets makes a difference too. I have to move pretty fast when casting 124 gr 9mm. I have to slow down a bit with 300 gr .452. I turn the pot temperature up a little on 9 mm and down a little on 452. Just some things to think about and experiment with.

reddog81 · June 3, 2020, 09:58 AM

I'd stick to one mold. If you're having problems getting one mold to run right there's no sense in trying to run 2 molds. A lot of time wrinkles show up because the mold is too cold. When I start a casting session I warm up the mold on a hot plate for a couple of minutes and then cast the first half a dozen pours as fast as possible to try and get the mold warmed up. usually after half a dozen to 10 pours and bullets will be coming out perfect.

BJung · June 3, 2020, 08:53 PM

Do you use single and double cavity molds? The 6 cavity molds look like they would take time to heat up. I'm thinking about buying 38-148gr and 9-120gr 6 cavity molds. The rest I might just use double cavity molds.

Do you place your molds on top of your lead pot on something to insulate it like a piece of wood?

big al hunter · June 3, 2020, 09:19 PM

Quote:

. Do you place your molds on top of your lead pot on something to insulate it like a piece of wood?

No, that would defeat the purpose. I set the bottom of the mold directly on the rim of the pot. The mold needs to be hot.

I only run the 2 cavity molds. If you want to run the 6 cavity Lee molds, look up Fortunecookie45 on YouTube. He loves the 6 cavity and shows how he uses it.

BJung · June 4, 2020, 12:05 AM

Big Al, where are you dropping your bullets? I am dropping mine to air cool because I want to drop them in water after powder coating from the toaster oven and get the hardest bullet. If I'm dropping the bullet on the ground when the lead solidifies on the sprew plate, that bullet is soft and will get dented, yes?

Your aluminum molds are always on the rim of the pot so it can stay warm. You watch the lead on the sprew plate solidify and then remove the bullet and repeat, yes?

Do you add lead to keep the gravity level up in the pot? Otherwise will the bullet weight change?

May 31, 2020, 08:50 AM	#1
BJung Senior Member Join Date: December 5, 2019 Posts: 773	Cast bullet reject rate What is your cast bullet reject rate? I'm new to casting and am using Lee Molds. If my cast bullets have folds, cracks or whatever you call them in the bands, I toss them into the pot. If those imperfections are slight, I'll save them into B Grade lot. Right now I'm re-melting maybe 5-10 percent. My B Grade pile is like 35-40 percent. However my .38 LHP casts are higher. I recently discovered to gently tap the dies from under to align them.

June 1, 2020, 01:46 AM	#6
BJung Senior Member Join Date: December 5, 2019 Posts: 773	wrinkled bullets Are wrinkled bullets rejected? I separated and used these to practice my powder coating today. Most will return to the pot. As for the rest, will the pistol bullets go straight?

June 1, 2020, 07:58 AM	#8
USSR Senior Member Join Date: November 14, 2017 Location: Finger Lakes Region of NY Posts: 1,442	I reject wrinkled bullets, bullets with a bad base or poorly filled out base, and bullets with poorly filled out driving bands. Don __________________ NRA Life Member NRA Certified Metallic Cartridge Reloading Instructor

June 1, 2020, 09:48 AM	#9
BJung Senior Member Join Date: December 5, 2019 Posts: 773	wrinkled bullets I'd reject bullets that have wrinkles at the base because the pressure would be applied differently. On all bands, gases will pass through. But what about wrinkles in some bands or on the front?

June 1, 2020, 12:55 PM	#11
FrankenMauser Senior Member Join Date: August 25, 2008 Location: In the valley above the plain Posts: 13,424	The larger the run, the lower the reject rate. Less than 50 bullets might have a 50% reject rate - poor fill-out, wrinkles, and even voids - usually from trying to get some heat into the mold. But if I run a few hundred of something, there usually aren't many rejects once the mold is up to temp and I've got my rhythm. Most of my bullets are intended for more than just plinking or casual shooting at short range. So, my standards may be a bit higher than average. Except for pressure test loads, and a few specialized applications, I don't allow any wrinkles. __________________ Don't even try it. It's even worse than the internet would lead you to believe.

May 31, 2020, 09:22 AM	#2
pete2 Senior Member Join Date: May 15, 2012 Location: Texas Posts: 2,566	I cast bullets for many years, once the mold comes up to temp you should get good bullets with very few rejects. The bullet alloy makes a big difference, I had to add a little tin to wheel weights to get good castings. Lino makes good hard bullets if you can get it. I used mostly cast iron molds but I do have a Lee one holer that as I recall works well. The molds can become too hot and cause frosted bullets, you can wait till they cool off a little, I actually used as many as 3 2 hole molds at the same time and kept them from overheating.

May 31, 2020, 10:38 AM	#4
reddog81 Senior Member Join Date: October 16, 2014 Location: Iowa Posts: 1,634	Once the mold is up to temperature my reject rate is maybe 5% at most. I preheat the mold and then toss the first couple of pours back. Once the wrinkles are gone and the rear driving band is getting complete fill out I start cranking them out and just pay attention to the bullet bases as I open the sprue plate. Usually upping the temperature a bit will help get better fill. If that doesn't work I'll add a little tin.

June 1, 2020, 01:48 AM	#7
BJung Senior Member Join Date: December 5, 2019 Posts: 773	Thanks for transferring my post Uncle Nick

June 1, 2020, 10:10 AM	#10
reddog81 Senior Member Join Date: October 16, 2014 Location: Iowa Posts: 1,634	I keep ones with "small" wrinkles that are not on the base. Unless you're going for sub 2" groups at 25 yards you'll never notice the difference. If your shooting for 2" groups at 25 yards I'd separate out the best of the best and go from there.

June 1, 2020, 01:21 PM	#12
BJung Senior Member Join Date: December 5, 2019 Posts: 773	wrinkled bullets with traditional lube v pc I would guess that pc would fill wrinkles better than traditional lubing. Or, is there a weight or distortion of the bullet under pressure issue?

June 1, 2020, 08:56 PM	#13
pete2 Senior Member Join Date: May 15, 2012 Location: Texas Posts: 2,566	I would reject all with visible defects. The more uniform the bullets the more accurate they are. You can take it a little further and weigh them after you cull the visible defects, I used to weigh round balls and reject the light ones. It just depends on how critical you want to be on accuracy.

June 2, 2020, 12:09 AM	#14
BJung Senior Member Join Date: December 5, 2019 Posts: 773	Casting bullets is really time consuming right now. Part of it is a learning curve, I'm sure. The best thing going for me now is that I'm practicing powder coating the wrinkled bullets and they're just going back into the pot. By the time my powder paint skills are developed, my casting skills will improve as well. I haven't weighed bullets yet as I am also not ladling lead into my molds but just pouring them from the bottom of the pot to the mold. This must effect the weight but I don't care at this point in time. I have other issues like wrinkled bullets do deal with.

June 2, 2020, 06:53 AM	#15
USSR Senior Member Join Date: November 14, 2017 Location: Finger Lakes Region of NY Posts: 1,442	burbank_jung, How are you preheating your mold? If you do it right and bring up to casting temperature, you won't have very many wrinkled bullets. Don __________________ NRA Life Member NRA Certified Metallic Cartridge Reloading Instructor

June 2, 2020, 07:13 AM	#16
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,061	For accuracy, wrinkles tend not to be evenly distributed around the bullet, putting its center of gravity off-center in the bore. That causes it to be flung away from the mean trajectory path at the exit from the muzzle, widening groups by drifting away from the center. Whether you have enough range and enough velocity in the drift away from the center to matter, depends on range, as suggested previously. But I have seen off-center bullet CG cause ten-shot .45 Auto target load groups sandbagged at 25 yards open from around an inch and three-eighths to about two inches. In that case, it was not wrinkles, but soft, short 185-grain swaged SWC's entering the throat slightly cocked that was causing the off-bore axis CG, and straightening their seating in the cases and going to headspacing on the bullet tightened things up. But that gives you some sense of the effect. Symmetrical bullet bases are the most important single thing. If those get off-axis or deformed, the uneven play of muzzle blast gasses off the base of the bullet pushing it laterally away from the bore axis and it can introduce a surprising amount of initial yaw. The last thing is the reason asymmetrical muzzle crowns open groups up. There is an element of randomness to the exact effect of the gases, and in one case I saw it lead to keyholing, and random scatter. Mind you, over a short enough range, even keyholing isn't a problem. Back when silenced .22's were considered the mark of the professional hitman, guns for that purpose would have the rifling reamed out to prevent ballistic matches from being made to recovered bullets (though you would think being caught with such a weapon would give the police a strong clue as to their suspect's occupation). Since the shots were fired at very close range, it made no practical difference. Hatcher even mentions the stopping power advantage of keyholing bullets. So everything depends on what your purposes are. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

June 2, 2020, 08:27 AM	#17
BJung Senior Member Join Date: December 5, 2019 Posts: 773	I preheat my molds now by inserting one edge into the molten lead. When casting, I rotate between two double cavity molds. Between the time I'm releasing bullets or refilling the lead, the other mold is resting on the aluminum plate under the pot.

June 2, 2020, 08:36 AM	#18
USSR Senior Member Join Date: November 14, 2017 Location: Finger Lakes Region of NY Posts: 1,442	Preheating your mold by simply putting an edge into the lead is not enough. Here is how I do it. I have a cast iron 6" skillet that I turn upside down and put on the stove burner. I then put the burner on it's lower setting and place the mold on the skillet for about 15 - 20 minutes which brings the mold up to casting temperature with few if any wrinkles. I cast with brass molds, so since you are using aluminum, alter accordingly. Hope that helps. Don __________________ NRA Life Member NRA Certified Metallic Cartridge Reloading Instructor

June 2, 2020, 09:14 PM	#19
BJung Senior Member Join Date: December 5, 2019 Posts: 773	The skillet idea will work. How about if I just take a propane torch to the mold and move the flame around?

June 3, 2020, 06:53 AM	#20
USSR Senior Member Join Date: November 14, 2017 Location: Finger Lakes Region of NY Posts: 1,442	That won't get you the slow and steady build up in heat that you want. Don __________________ NRA Life Member NRA Certified Metallic Cartridge Reloading Instructor

June 3, 2020, 09:58 AM	#22
reddog81 Senior Member Join Date: October 16, 2014 Location: Iowa Posts: 1,634	I'd stick to one mold. If you're having problems getting one mold to run right there's no sense in trying to run 2 molds. A lot of time wrinkles show up because the mold is too cold. When I start a casting session I warm up the mold on a hot plate for a couple of minutes and then cast the first half a dozen pours as fast as possible to try and get the mold warmed up. usually after half a dozen to 10 pours and bullets will be coming out perfect.

June 3, 2020, 08:53 PM	#23
BJung Senior Member Join Date: December 5, 2019 Posts: 773	Do you use single and double cavity molds? The 6 cavity molds look like they would take time to heat up. I'm thinking about buying 38-148gr and 9-120gr 6 cavity molds. The rest I might just use double cavity molds. Do you place your molds on top of your lead pot on something to insulate it like a piece of wood?

June 4, 2020, 12:05 AM	#25
BJung Senior Member Join Date: December 5, 2019 Posts: 773	dropping your cast bullet Big Al, where are you dropping your bullets? I am dropping mine to air cool because I want to drop them in water after powder coating from the toaster oven and get the hardest bullet. If I'm dropping the bullet on the ground when the lead solidifies on the sprew plate, that bullet is soft and will get dented, yes? Your aluminum molds are always on the rim of the pot so it can stay warm. You watch the lead on the sprew plate solidify and then remove the bullet and repeat, yes? Do you add lead to keep the gravity level up in the pot? Otherwise will the bullet weight change?