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Introduction
In Part 1 of this article, I described in detail the eight phases of what I call
the ?ing Cycle? the role each phase plays in our attempt to cast high
quality bullets within a narrow weight range on a consistent basis. To review,
the Casting Cycle as I described it consists of the following eight phases:
Phases
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Activity |
Phase 1 |
Filling the Dipper / Ladle With Melt |
Phase 2 |
Pouring The Melt Into The Mould |
Phase 3 |
Forming the Sprue Puddle |
Phase 4 |
Waiting for the Melt to Frost |
Phase 5 |
Letting The Melt Harden |
Phase 6 |
Cutting the Sprue |
Phase 7 |
Dropping the Bullet |
Phase 8 |
Closing the Mould and Setting-Up
for the Next Bullet |
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In that article I also stressed the importance of keeping the mould at or near
the same temperature for each bullet cast in order to achieve maximum results. I
believe that the key to casting one bullet after another within a few tenths of
a grain is repeating each of the eight phases of the Casting Cycle as close to
the same way as possible from one bullet to the next. By doing so, we can keep
the temperature of the mould within a few degrees with each bullet we cast,
which in turn helps to eliminate wide fluctuations in weight.
Simple Accessories To Make Your Casting Better
Now I would like to discuss how you can use several inexpensive accessories that
you may already own to make your casting more consistent and productive.
Hopefully these suggestions will help you to achieve better results and enjoy
your casting sessions a little more.
1) Use A Secondary Source Of Heat For Your Mould And Tools
Getting your mould up to casting temperature initially and then keeping it there
when you take a break to flux the melt or make a run to the bathroom can be a
problem. Some casters recommend heating the mould initially with a propane torch
or by standing it on the edge of the pot to warm up. Others simply place the
bottom of the mould directly on top of the melt in order to heat it up quickly.
For me, a safe and inexpensive solution has been to use a $ 20.00 electric
hotplate, available at most hardware and discount stores, as a secondary heat
source.
At the beginning of each casting session when I fire up my plumber?rnace, I
also turn on the hotplate and set my mould, dipper, and dross-skimming spoon on
top to be heated. Ten or fifteen minutes later when the melt has reached the
desired casting temperature, my tools are also hot and ready to use. After
casting just a couple of bullets, the temperature of the mould is where I want
it to be and the bullets begin dropping out at the designated weight I have
targeted.
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A hotplate
will help to keep your casting tools hot and ready to use while you take a
break or flux the melt. |
If I take a break or need to flux the melt, the dipper and mould go back on
the hotplate where they stay hot until I?ady to use them again.
Surprisingly, my hotplate can keep my mould at or slightly above its optimum
casting temperature. Using a hotplate has eliminated the significant drop in
mould temperature that I would previously encounter when taking a break. In
those days, when I resumed casting after a break, I had to make a handful of
bullets before the mould would return to my desired temperature again.
The hotplate also provides me with an added level of safety. Allowing my tools
to heat up for several minutes on the hotplate before my casting session begins
allows any moisture or condensation that might be present on my tools to
evaporate. It also eliminates the dramatic temperature differential between the
800 degree melt that I use and my casting tools that occurs in the wintertime.
Dipping a cold spoon or ladle into an 800 degree pot full of molten lead can
certainly add an unwanted dose of excitement to your life.
2) Weigh Your Bullets As You Cast Them
Every reloader owns and uses either an electronic or manual beam scale. Using a
scale to weigh your bullets as they are cast is certainly not a new idea, but I
believe that it is the single most valuable source of information about how well
you are casting.
After dropping each completed bullet from the mould onto a padded surface, I
immediately place it on my Dillon electronic scale and start pouring the next
bullet. As I?ing so, I quickly glance at the display on the scale to see
exactly, to within one-tenth of a grain, what the last bullet weighed. Knowing
the weight of each bullet immediately after it is cast helps me in three ways:
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Weighing your bullets as you cast them is probably the single most productive
step you can take towards casting better bullet |
A) It Tells Me When The Melt is Too Hot
If I have been casting my bullets consistently within a given weight range and
have not broken my rhythm, and a bullet drops out of the mould several tenths
above where the other bullets have been, there?good chance that the melt is
20 to 30 degrees hotter than the 800 degrees that I want.
The higher weight is a red flag to check the temperature of the melt and to make
the necessary adjustments needed to get the pot back down to 800 degrees.
B) It Tells Me When The Mould Is Too Hot or Too Cool
Once again, if the weight of my bullets start to gradually increase or decrease
over a span of 3 to 5 bullets, it probably means that the mould is either
getting too hot, or is cooling off too much. In either case, equipped with that
information, I can adjust the amount of time I am allocating for Phase 5 of the
Casting Cycle (Letting The Melt Harden) to compensate.
If the bullet weights are increasing it means that the mould is getting too hot
and I need to allow more time for the melt to harden, thereby adding several
seconds for the mould to cool. If the bullet weights are decreasing it means
that the mould is cooling off too much and I need to shorten the amount of time
I am allowing the melt to harden, thereby giving the mould less time to cool.
C) It Helps Me To Quickly Identify Rejects
If a bullet is significantly underweight, I know immediately that there is a
void inside and I set that bullet aside in a pile to be used as fouling rounds.
Although I usually know from experience when I have cast a bad bullet (generally
because I did a sloppy job in Phase 1 or 2) the weight of the bullet confirms
that fact. The out-of-weight-range bullet is simply a red flag to do better on
subsequent casts.
Some Tips For Electronic Scale Users
If you use an electronic scale, here are a couple of helpful tips:
* Plug in your scale at least 10-15 minutes before you plan to use it. If
possible, plug it in several hours before you begin to cast. That will give the
unit sufficient time to warm up and stabilize. If I weigh a bullet immediately
after turning on my scale and then again 30 minutes later, I will receive up to
a one-half grain difference in weight. This is especially important if you have
to cast in the frigid confines of the garage in wintertime. Outside air
temperature can definitely affect the accuracy of your electronic scale.
* Be aware that most electronic scales are very sensitive to air movement and
vibration. When I first started using my Dillon electronic scale to weigh
bullets as I cast them, I was very disappointed in its performance. Although it
had always performed well to weigh powder charges at my reloading bench in the
basement, it seemed to take forever for the scale to arrive at a final weight
when I used it to weigh bullets at my casting bench in the garage. It was not
uncommon for the digital display to flash a series of numbers for 10 or 15
seconds before finally arriving at a final weight.
After talking to the people at Dillon Precision Products, I learned that their
electronic scale is very sensitive to both air movement and vibration. To solve
the problem, I constructed a small enclosure for my scale that shields it on
three sides from moving air currents. I then mounted the enclosure on four soft
rubber feet to help absorb any vibration that might be transmitted through my
casting bench. The enclosure did the trick! Now when I place a bullet on the
scale I receive a final weight instantly, with no variation or indecision on the
part of the scale.
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The use of this small enclosure eliminated unreliable weight readings from my
electronic scale caused by air movement and vibrations in the casting area. |
* Don?rget to use some type of insulated pad under your freshly cast,
red-hot bullet when you place it on your scale. I use a 1" by 1" piece of 1/4"
Masonite for this purpose. Prior to that, I used the thick aluminum cap from my
Lyman 55 powder measure. The first time you forget to do this, that beautiful
bullet you just cast will melt a dimple into the smooth plastic platen on your
scale.
3) Use A Clock To Monitor Your Casting Cycles
An inexpensive battery-operated analog clock with a second hand can be just the
thing to help you keep a precise, consistent cadence when you cast. I purchased
the one I use at my local Target store for about $6.00. Although many casters
simply count in their heads to maintain their casting rhythm, I prefer to let
the clock do the job for me.
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Using a clock will help you to more precisely manage the critical phases of the
Casting Cycle and maintain your cadence from bullet to bullet. |
The reason I use an analog clock with a second hand instead of a modern digital
clock is personal preference. Looking at the face of the analog clock gives me
an instant picture of where I am in the overall Casting Cycle. I generally
glance at the clock as soon as the sprue puddle on top of the mould cools enough
to get that frosted appearance (Phase 4).
It? that moment that I start Phase 5 of the Casting Cycle (Letting The Melt
Harden). If I?locating 15 seconds for Phase 5 and the second hand is, for
example, at the 12 o?k position on the dial, I wait until the second hand
reaches the 3 o?k position before I cut the sprue. The clock allows me to
time this important phase of the Casting Cycle precisely from one bullet to the
next.
Glancing at the clock also helps me keep the overall time of each Casting Cycle
the same from one bullet to the next. If it takes you 45 seconds to cast one
bullet and 60 seconds to cast the next bullet, that time difference is going to
show up in the weight of your bullets.
Finally, the clock also helps me to more precisely lengthen or shorten any phase
of the Casting Cycle to keep the mould temperature where I want it to be. Using
a clock as a casting aid doesn?an staring at it for each of the eight phases
of the Casting Cycle. Simply use it as a reference to keep things in sync from
one bullet to the next.
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An analog clock with a second hand provides an instant snapshot of the entire
Casting Cycle time period. |
If you currently don?e a clock when you cast, you might find it interesting
to see how consistent you are (in terms of overall time per bullet) from one
bullet to the next. The next time you are casting and producing high quality
bullets, have a friend or family member time you through the eight phases of the
Casting Cycle. Have them record how long it takes for you to complete each phase
of the casting process. Do this for 10 or 15 bullets.
After your casting session is over, take a moment to add-up the time for each
bullet and analyze the results. Pay particular attention to how consistent you
are in Phase 5 of the Casting Cycle from one bullet to the next. You might be
surprised by the results.
4) Use a Small Fan to Regulate the Temperature of Your Mould
Here?mething that I believe holds a great deal of promise in helping to
control the temperature of the mould even more. I recently starting using a
small electric fan to cool the mould during Phase 5 of the Casting Cycle. Before
I used the fan, I was having to wait as much as 30-45 seconds in Phase 5 for the
mould to cool enough to get the weight I wanted.
Now, as soon as the sprue frosts over in Phase 4, I set the mould on a small
wooden block in front of the fan and wait 10-12 seconds. The fan bathes the
mould in a constant, even stream of cool air. In the two sessions where I used
this method, my bullet weights were incredibly consistent. By adding or
subtracting one or two seconds to this phase of the Casting Cycle, I could
almost predict how much the bullet was going to weigh to the tenth of a grain.
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A small electric fan seems to add a degree of stability to the casting process
by bathing the mould in a constant stream of cool air. |
The outside air temperature during those 2 casting sessions was 55 degrees. I?anxious to see if I can achieve similar results in the bitterly cold
temperatures of a typical Chicago winter. In my opinion the use of a small fan
may add an important stabilizing element to the casting equation.
Some Additional Ways of Achieving Consistency
The secret to casting nearly identical bullets requires performing the eight
phases of the Casting Cycle the same way every time while trying to keep all of
the other variables the same (i.e. melt temperature, air temperature, air
movement, etc...). Changing even one element in the casting equation makes your
job that much harder.
So here are a few suggestions to think about the next time you fire up the pot
to cast some bullets:
Start The Season With The Largest Batch of Uniform Alloy Possible
At the beginning of each shooting season, prepare your alloy so that each ingot
you put in the pot during the year is exactly the same. Mix the largest batch of
alloy you can manage and cast it into small, manageable ingots. If you can,
purchase several hundred pounds of alloy at a time, if storage space and money
are not a problem. Then load it by weight into a large 40 or 50 pound pot, melt
it down, mix it to your desired hardness, and cast it into smaller ingots
appropriate for the size and type of pot you are using.
Lyman and RCBS make ingot moulds that work well for this purpose. I like to cast
my ingots in heavy-gauge aluminum mini-muffin baking pans which you can find at
any grocery or hardware store. They堩nexpensive, durable, and each one allows
me to cast 12 small round one-half pound ingots. I purchased 10 pans that I use
when I melt down the larger seven pound ingots I get from my alloy supplier.
Because they are made from heavy-gauge aluminum, molten lead doesn?ick to
them and they clean up in a snap.
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Inexpensive aluminum mini-muffin baking pans make ideal ingot moulds when
melting down larger bars of alloy into more manageable sizes. |
If you shoot several different guns and each has an appetite for a bullet with a
different hardness, your batches will probably be smaller than someone like me
whose primary gun prefers a 20:1 mix.
A Word of Caution!
If you do use aluminum baking pans to cast your ingots, be sure to allow the
ingots to harden and the pans to cool sufficiently before you empty them. If you
pick up an aluminum pan filled with lead while it is still hot, it will have a
tendency to sag badly or buckle from the weight of the melt. That?e reason
why I purchased 10 pans. It allows me to cast 120 small ingots before I need to
empty the first pan. By that time, the first pan has cooled enough for me to use
it again.
By mixing your alloy in a large quantity and weighing the lead and tin when you
do so, you will achieve the most consistent and uniform alloy possible.
Use a Reliable Heat Source
If you use an electric furnace to melt your alloy, pay attention to where the
thermostat is set and how often it cycles on and off. Measure the temperature of
the alloy when the pot reaches its designated temperature and the thermostat
light goes off (the high end of the temperature range). Then measure again when
the light goes on, indicating that the temperature of the melt has fallen below
an acceptable level and the thermostat has kicked in to start the pot heating up
again (the low end of the temperature range).
How large is that temperature spread? Does your pot keep the melt within a 10 or
20 degree range, or is it more like 50 degrees from its high to low setting?
Once you have tweaked your pot to produce a relatively narrow temperature range,
mark the dial settings and use them every time you cast. Although you may need
to adjust your settings slightly to maintain your desired temperature as the
level of the melt in the pot drops, don?t into the habit of constantly
changing settings during your casting session.
If you use a propane-fueled heat source like a plumber?rnace, turkey cooker,
or camp stove, start with a full tank of fuel and track the number of hours you
use it for your casting sessions or weigh it before and after each casting
session to get an idea of how much fuel you use per hour. Then watch to see when
you start to get erratic heat production. As the amount of fuel in the tank goes
down, so too will the efficiency of the burner. Usually after the fuel level in
the tank has fallen to somewhere between one-half to one-third full, you will
notice that the temperature of the melt will drop by 20 or 30 degrees, even
though the burner control valve is set at the same spot that it was when the
tank was full.
I use a plumber?rnace, and after about 10-12 hours of use, I either switch
to a full tank or get the one I?ing refilled. Having a reliable source of
heat for your casting operation is critical for efficient and productive
casting.
Develop a Standard Routine for Fluxing
Here?point that everyone has an opinion about: how often to flux. Some
people say to flux at the beginning of the casting session and then again after
every 30 to 40 bullets. Others recommend fluxing the melt after every 10 or 20
bullets.
Experiment with each technique and then use the one that seems to work for you.
The key is to do it the same way every time. Once again, what we are trying to
achieve is consistency. Only by being consistent in every aspect of our casting
operation can we achieve the highest results.
To help me keep track of how many bullets I have cast, I constructed a simple
counting device using 15 plastic golf balls that slide from side-to-side on a
small diameter metal rod about 30 inches wide. It looks like a poor man?abacus, but it works. The reason I use the plastic golf balls is because they
are large enough for me to manipulate while wearing leather gloves. When I have
completed a bullet I slide one of the golf balls to the other end of the rod.
When all 15 balls have been moved from one side to the other, I know it?me
to flux the melt. Any number of other methods will work just as well (i.e. using
a small calculator, a cork board with push pins, a small chalk board, or moving
marbles from one bowl to another).
Add Metal To The Pot At Set Intervals
Here?other element of the casting process with no right or wrong answer ?dding metal to the melt while casting. Some people believe in throwing their
sprue cutoffs and deformed bullets back in the pot as they cast. They believe
that adding material in such small amounts will have the least impact on the
temperature of the melt.
Others choose to accumulate a larger quantity of material, say after 50 or 100
bullets have been cast, and then add it all to the pot at one time. I happen to
be one of those who subscribes to this procedure. The reason I do it this way is
because I usually need a short break after casting about 100 bullets anyway. So
I welcome the opportunity to stop for a short time to allow the melt to come
back up to temperature once the scraps have been added.
The reason we pay attention to this element of the casting process is because
adding metal to the pot during our casting session can have a rather dramatic
impact on the temperature of the melt. Adding a large quantity of metal to the
pot at once can lower the temperature of the melt by as much as 100 to 150
degrees. That kind of temperature change will definitely change the quality of
the bullets you are casting, until the melt returns to its previous temperature
A friend and fellow BPCRS shooter, George Liotta, casts a small quantity of
ingots at the beginning of each casting session and then sets them on top of his
electric pot to stay warm. George believes that using ingots made from the same
batch of melt with which he is casting insures a more uniform mix. Casting the
ingots at the beginning of his session also insures that the ingots will be hot
when he adds them to his melt later and therefore will have little impact on the
temperature of the melt. Decide what makes sense to you and then make that your
standard procedure for adding metal to the pot when you cast.
Determine Which Dipper or Ladle Works Best With Your Mould
Just like every gun seems to have a particular load and bullet hardness
combination that it likes best, so to do your moulds. If you own more than one
type of dipper or ladle, determine which one works best with the mould you are
using.
I own several dippers including ones from Lyman and RCBS, and a bottom-pour
Rowell ladle. Try as I may, I cannot consistently cast high quality bullets
using the Rowell ladle with my Lyman Postell 457132 mould. For some reason, my
bullets will vary by as much as a full grain from one bullet to the next. On the
other hand, when I use my RCBS bottom-pour dipper, I can cast bullets within a
few tenths of a grain all day long.
Why? Perhaps it?cause when the dipper is sitting directly on the mould as
the melt is pouring into the cavity, the pressure of the melt as it enters the
mould is more consistent from one pour to the next. Of course, in order to
achieve this, I have to make sure that I fill the dipper the same way each time.
Having the dipper half-full one time and full the next will also affect the
weight of the bullet cast.
Control Your Casting Environment As Much As Possible
Although you may not have given it much thought, where and when you cast can
have a definite impact on the quality of your casting. If you have an enclosed
space where you can control the temperature and air flow around your casting
area (keeping in mind the need for adequate ventilation) you have a leg up on
those of us who have to cast in our garage or outdoors.
My casting bench was initially located at the far end of my garage and sat under
a large window to the outside. I constructed a small 3-sided enclosure around my
furnace and pot in front of the window (top and both sides) and placed a 20" box
fan on the window ledge. This proved to be a very efficient arrangement. The box
fan drew any smoke or fumes away from my casting position and vented them to the
outside.
For safety reasons, I leave the garage door partially open to provide fresh
outside air. Unfortunately, the outside air on any given day can vary by as much
as 80 to 100 degrees depending upon the season of the year. As a result, the
length of my Casting Cycle varies slightly from month-to-month based upon the
temperature and humidity of the air.
Believe it or not, even changing the speed of a box fan in the window can
adversely affect my casting. One day I changed the speed of the fan from medium
to low. Within just a few minutes I noticed that my bullets were casting nearly
a full grain heavier. I finally figured out that when I changed the speed of the
fan, it reduced the movement of air through my casting area and affected the
temperature of both my mould and melt. As a result, both the mould and melt were
getting hotter with each bullet I cast.
When I realized what I had done and its impact on my casting, I returned the fan
to its original setting and watched my bullets return to their previous weight
range. If you use a fan to ventilate your casting area ?st set it and forget
it?>
If you cast outdoors, your challenge is even greater. Changing temperatures and
variable air currents make your job the hardest of all. If you can, try to cast
at the same time on calm, nearly windless days or days when there is a steady
breeze to carry away smoke and fumes. Early morning or early evening would seem
to be the best times to try to cast due to the lower temperatures encountered.
Conclusion
I hope that the information presented in this two-part article has been useful.
I?nfident that if you understand the Casting Cycle and look for ways of
making your casting routine more consistent, you?oon find yourself casting
better bullets more often! If you have any comments or questions about anything
I have presented in this article, I would like to hear from you. Simply e-mail
me at darrylray@longrangebpcr.com.
By Darryl Hedges
Copyright?0 All Rights Reserved.
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