In my quest to make my shooting better/faster, without spending too much money, I decided to give bullet casting a try. I knew from watching a friend cast fishing weights, I needed a new angle. After little research I came across Magma Engineering. The company sells a very high volume casting machine (19,000hr) and a slower one called the Master Caster they said would do 500-800an hr. So I looked at the pictures they had and dusted off my drafting scale. The machine is based on a cast aluminum frame (which I couldn’t make) and was manually operated (which I didn’t want), but it didn’t seem overly complicated. So I ordered a set of molds from them for 230grn LRN .45. I made a melting pot from 7” round pipe with 3/8” wall, it’ll hold just under 60# of lead (1750 bullets worth). Wrapped it with a new (a used one doesn’t like to bend) 3500-watt oven element I got from the Sears repair center ($9.47). I had a few Yokogawa PID controllers, so I used one of them for my thermostat. I hooked the controller to a 12v dc actuated 230v ac solid state relay. I was then melting wheel weights. I soon covered the element with .045 stainless steel to keep the heat in and off my face. Once I got the bullet mold ($65 & almost three months later) I built a frame out of 1”X1” .095 mild steel. I used double split set collars (2.25 ea.) to hold the oil lite bearings (1.14 ea.), for the main shaft (3/4” OD); this will provide easy maintenance in the future. The mold carriers were machined from 1” solid stock. I rolled ½” solid rod for the guide rods to hold the mold shut. Sections of 5/16 24tpi all thread were used on the sides for adjustment. I decided that sitting around pushing a lever (to let the lead flow), and pulling a handle (to throw the bullets out of the mold) might get in the way of some “quality time”. So I went through my stuff and came up with a gear reduced motor that ran at 4rpm. With two bullets in the mold this came out to 480 bullets an hour, about right. Then I hooked a solenoid to an arm that pulled a ¼ stainless steel rod from the bottom of the pot; a ¼ 20 bolt can be adjusted for the amount of flow. Under the pot I milled a slot that diverted the molten lead to the stainless steel orifice plate that has two holes in it the correct distance to hit the center of the mold holes. The solenoid is controlled by a home made timer (duration of flow) using a 555 integrated circuit (from Radio Shack). I can adjust the pour time from 0 to 10 seconds with 10 turns from a 0-1meg ohm potentiometer (1 sec a turn). This fine adjustment is needed for the sprue (part above the actual bullet/s) to fill properly without spilling over. A double pole single throw switch controls the whole process. When the actuating arm hits the switch, the timer, with a double pole double throw relay, stops the motor while simultaneously pouring lead. As soon as the timer stops the flow of lead the motor begins to drive the mold down, cutting the sprue then hitting two pieces of angle iron that split the mold apart, dropping the sprue into one divider and the bullets into another. Then the process begins again. I found a fan is needed to keep the mold cool enough for the 480 rnd an hour pace, in summer heat. I also added an extra timer for a cool down pause (1-30secs), after the mold opens, to further cool if needed for 350 + grn bullets. The last addition (not in photos) were two 12vdc solenoids to tap the mold carriers, to knock a bullet out if it happens to get stuck. It’s still not finished out, but you can see how it works.
After a few hours of playing with my new toy, I had quite a pile of bullets. They were though, a few thousands over .452. I looked at the sizers available and again they were slow or expensive. A trip to CDC surplus got me a 3” pneumatic ram with integral limit switches for $25. I machined a sizing die from stainless steel. Mounted it all to a piece of 3/8” plate steel. I used a double split set collar to hold the sizing die in place, this will allow for different calibers. I machined a piece of brass that threaded into the ram to drive the bullet through the die. I made a bullet carrier from UHMW to carry the unsized bullets from a feed tube to the mouth of the die. The carrier rides in an aluminum housing that has a momentary switch on the end. When the carrier goes in, far enough for the bullet to drop in the die, it hits the switch that drives the ram down to it’s limit then back up. After this process the bullets are perfect .452. I am still experimenting with different bullet lubes; however, I have been using a water based dry lube for forming steel that seems to work well (just dip and let dry).
One interesting thing, I can, by changing the alloy of the bullets, make anywhere from 210grn to 240grn bullets from the same mold. Cost per loaded round using free wheel weights, range brass and ba10 powder 1.8 cents a round.
