Tips for using a 502-700 and other .502” & .512” MP Molds

(700grs “Grand Canyon” HP/FP)

1) Clean this mold completely before use to remove machining oils, which will otherwise cause wrinkles when the oils burn off.

2) I would run the mold halves through at least two (and three would be better) 400+ degree (Fahrenheit) heat cycles in the oven to “normalize” the brass after machining. Best done with the two mold halves wired together so that the alignment pins assist with the normalizing process. Allow to air cool to room temperature between cycles. I started doing this for aluminum molds, and have continued the normalizing with machined brass molds. Miha’s work is amazing, and the molds seem to like the break in cycling.

3) There’s a LOT of brass here. Either use a hot plate, or dip the corner of the mold into the lead FOR A LONG TIME to allow it to come up to proper operating temperature.

4) You will likely NOT have much success with this mold if you try to get it up to running temperature by filling cavities over and over and over again. The mold needs to get up to a HOT temperature to fill properly for these big bullets, especially when running the hollow point inserts.

5) You will find that you need to start off with the alloy temperature a bit on the hot side, and then adjust downward as the mold and the alloy find the mutual perfect place.

6) When the mold and the alloy are at the perfect temperatures, I am easily able to open the sprue plate with a leather-gloved hand (no banging on the sprue plate!)

7) 10 bullets is a pound of lead, so in my mind adding the sprue cut offs immediately back into the pot is a big deal. I drop the cut sprues into my gloved hand, and slip them into the pot for re-melting. This also lessens the heat shock that putting otherwise room temperature sprues into the pot would cause.

8) These bullets are big and dense. The guys who got two molds were the ones wearing the wise and smart caps! It takes a long time for the centers of these big boolits to solidify. So, be patient. While one mold is setting up, you can be pouring the other one. Don’t try to open the molds too soon, you will be ripping and tearing the edges of the hollow points. If you only have one mold, be patient with the set up time. Cut the sprues early though, while everything is still sizzling.

9) I use one of my mold tappers to gently (very light taps…) tap on the pivot screw for the mold handles to create a vibration that eases the mold halves away from the boolits. The boolits should gently fall out with a large thud. I place the mold down on the landing area while doing this tapping. The molds are heavy, and the filled cavities make them even more so.

10) For that reason, use a few cotton or linen cloths in the landing zone for the falling boolits. The boolits are heavy and still kind of soft when you ease them out of the mold halves. You don’t want them banging into your catching area or into each other. And, they will take a long time to cool to room temperature. I don’t like water cooling these boolits. Too much opportunity for boolit on boolit damage.

11) If you have all your temperatures right, you should get nice shiny boolits without having to bang the heck out of the molds. If you treat these molds properly, they will make T-Rex bullets for hundreds of years. Maybe millions.

12) If you are winging it like I used to do, a mixture of 50% wheel weights, and 50% range lead or pure lead is just about right for these boolits. Lyman #2 works well. Add some 60/40 solder if you need to for filling the edges of the hollow points, but don’t go crazy on the tin. No need.

13) There is also no need for “smoking the molds”… These are high quality molds. They should be ready to run and will drop boolits well without any butane smoke.

Orville Deutchman (DukeInFlorida)

http://castboolits.gunloads.com/showthread.php?344846-Mihec-502-700-Mold/page11

Comment by Miha Prevec (MiHec): Orville Deutchman also known as DukeInFlorida at Castboolits.com is a NRA Certified Metallic Reloading Instructor and hosts Full Day – Cast Bullets Workshops in the Eastern Florida area. He also has very good reloading instructions for 500 S&W Magnum.

http://www.floridareloading.com/index.php/2017/02/04/reloading-for-sw-500-magnum-ouch-or-ahhhhh/

More from Duke: web page: http://www.floridareloading.com/

Photos: (all photos by Orvile Deutchman)