WW cast bullets are gaining weight?

[Slim Chance Pistolero]

this is my first post to this forum, but not my first forum ... been reloading bullets since 1974 but just started casting my own bullets this past month ... my wife and i cowboy action shoot so we go thru alot of bullets ... bought a Lee 358-125-RN six cavity mold ... using WW ... watched alot of elvisammo utube stuff and have learned how to begin casting, ( sorting WW for AL, steel and zn ) and PC ... casted about 2,000 bullets that are shinny, sharp edges and weigh about 126 gr .... got a new batch of WW, sorted for bad stuff, molded ingots ( looked a little frosty ) and molded about 365 nice bullets that were shinny, sharp edges and weighed 134 gr ... that is my problem, WHY does this set of bullets weigh so much more????
BTW, i search this sight for answers and did not find anything ... have read most threads concerning casting lead and equipment here and find most VERY helpful

[John Boy]

No mold should cast bullets the nominal weight of the mold at one casting and then an extreme weight difference the next casting ...
* Is this weight difference measured on naked bullets or lubed bullets for each batch of bullets
* Was the hardness measured for each batch of bullets
* How long after each casting session were the bullets weighed
* Were bullet batches weighed with a beam scale or a digital scale
* If a digital scale, calibrate it and weigh each batch again and same for beam scale
Reply to each question

[winelover]

Best guess, is that the composition of WW alloy was slightly different........a little softer (more pure lead than Sn or Sb). Pure lead weighs more than tin or antimony.

Cast bullets will not gain weight, only diameter, over time. However that takes a long time.

Cast bullets will increase in hardness, over time. It takes about three weeks to attain near maximum BHN stability. They will increase, slightly more, but that takes years.

Don't over think the hobby. It's not rocket science. Just strive to make usable bullets for maximum enjoyment.

Winelover

[lar45]

Maybe you had more stickon wheel weights in the second batch. This would give you a different composition, ^^^ What He said ^^^
Many of us sort out the stickon wheel weights and melt them down separately for when we need pure lead...

[RU shooter]

What was the diameter outa the mould from the first batch versus the second batch ? If the second batch was dropping bigger that would explain the increased weight somewhat . And as others said the first alloy was different than the second .

[Slim Chance Pistolero]

i reweighted 4 different batches ...
* Is this weight difference measured on naked bullets or lubed bullets for each batch of bullets
called batch #1 (PC eastwood red), #2 (PC eastwood blue), #3 (PC eastwood red) and #4 (store bought lubed 124 gr)
* Was the hardness measured for each batch of bullets
NO, did NOT do any hardness testing, just pb WW for cowboy shooting
* How long after each casting session were the bullets weighed
for the PC bullets about 2 days between each batch, lubed bullets have no idea
* Were bullet batches weighed with a beam scale or a digital scale
average of 5 bullets
RCBS 5.0.5 beam scale by batch #
#1 = 130.2 #2 = 128.2 #3 = 132.0 #4 = 135.2
RCBS Electronic Range Master 750 digital
#1 = 130.3 #2 = 128.8 #3 = 132.1 #4 = 135.0
Homgeek digital scale model "TL series"
#1 = 130.4 #2 = 128.7 #3 = 128.9 #4 = 135.1

* If a digital scale, calibrate it and weigh each batch again and same for beam scale
Reply to each question

did what you wanted and found about 2 gr difference between batches, NOT what i thought i had in the beginning ... other finding were, the bought cowboy bullets ( #4 ) we much heavier that stated on label and were relatively close to the beam scale...
before casting i just bought the lead bullets and assumed all was as stated on the labels, found that NOT to be true, thanxs for asking the right questions to answer my question
now i can rest easier and not put my new bullets on a diet

[Slim Chance Pistolero]

Winelover
Don't over think the hobby. It's not rocket science. Just strive to make usable bullets for maximum enjoyment.

i think you hit the nail on the head ..... scp

[Slim Chance Pistolero]

these had NO stick on WW ... i also "sort out the stickon wheel weights and melt them down separately for when we need pure lead"
scp

[Slim Chance Pistolero]

RU shooter ..diameter outa the mould was consistant between batches #1, #2, and #3 but #4 was 0.004 smaller

[farmbif]

.004 smaller is quite a difference,
im guessing you made ingots out of your wheel weights are these four batches from the same pouring of ingots?
there are some big differences in composition of clip on wheel weights, ive noticed that the giant old time truck wheel weights are a whole different alloy than modern ones for car tires that are painted.
I'm no expert but do know that these differences in composition have effect on final cast bullet size.
I mix them all together and make a load of ingots.

[Larry Gibson]

One other potential cause; When casting with a Lee 6 holer if you are holding onto the sprue opener handle while casting it can slightly open the bottom of the block. That slight opening is difficult to see unless you turn the blocks over while holding all 3 handles together. Thus the bullets are sort of "beagled" which increases the weight slightly. When the sprue plate is closed I very slightly back the handle off just enoght to not start the sprue plate open. Then I hold only the mould block handles when casting.

[fredj338]

No mold should cast bullets the nominal weight of the mold at one casting and then an extreme weight difference the next casting ...
* Is this weight difference measured on naked bullets or lubed bullets for each batch of bullets
* Was the hardness measured for each batch of bullets
* How long after each casting session were the bullets weighed
* Were bullet batches weighed with a beam scale or a digital scale
* If a digital scale, calibrate it and weigh each batch again and same for beam scale
Reply to each question

Sure it can if the alloy changes. The OP issue is his new batch of ww has more pure lead.

[Slim Chance Pistolero]

farmbif ... i cast lots #1, #2 and #3 from the same mold ... BUT i bought lot #4 AND #4 is the 0.004 smaller size

[Conditor22]

First off, welcome to CB and the maddness

OK let's back up to the beginning.
1) what pot are you casting with?
2) bottom pour or a dipper?
3) how hot is the alloy in the pot?
4) did you control the heat with a PID?
5)IF no PID how did you measure the heat in the pot?

Using hotter temperatures to cast will cause the alloy to expand then the boolits to shrink more weighing less than boolits cast at a cooler temperature

Casting to fast will heat up the mold more having similar results (and tears/divots on the bottom of the boolits) Mold temperature has an effect on boolit size. High-end molds come with the option of being pre-drilled for a thermocouple to monitor the mold temperature.

Not having the mold closed the same on each cast will give you differing boolit hardnesses

COWW Clip-On Wheel Weights from different factories and of different ages have different compositions so the odds of 2 batches of COWW weighing the same is slight

Frosty boolits mean the mold or alloy is hot or you're casting a little fast.

The trick is to get into a rhythm and maintain it until done.

throwing sprues back into the pot will affect the temperature of the pot until it recovers.

many say that a 2.5 to 5% weight difference isn't a problem for most reloading/shooting applications

[Slim Chance Pistolero]

thanxs for the welcome ...
am casting with a lee 4-20
bottom pour
540 - 600 degree
No PDI
digital thermometer
some ingots were frosty but all bullets were shinny with sharp edges
the ingots were from 2 different batches
i do not thro the sprues back in the pot, put them on a tray and when returned to the pot i take a short break
rest the mold on top of pot while waiting for pb to come back up to temp

[robg]

add some tin as there may be more lead % in the alloy

[Conditor22]

540 - 600 degrees is really cold even for a hard alloy. I do most of my casting between 680 and 720° (except pure where I go 750°)

boil some water and see if the thermometer reads 212F.

resting molds on top of the pot help but a cheap hotplate ensures the molds will stay at casting temperature when you start or continue casting.

with cooler molds when you start and continue casting you will get different sizes/weights than when the mold(s) are up to temperature

shinny generally means cooler alloy/mold (not a bad thing) many prefer frosty, I aim for somewhere in between.

[JonB_in_Glencoe]

Like Larry said, I am thinking you are not closing the mold correctly and/or not holding it closed correctly. That can make a huge difference in consistency. Because all your boolits from that 125gr mold, should be within one grain of each other...when you get real good at casting, the weight range should be even tighter.

[softpoint]

Holiday season! Everything gains weight between Thanksgiving and Christmas!