H&G Mold with bottom pour Lee pot technique

[Tmaloy]

So I got my Lee 4-20 pot setup the way I wanted. Tried it with a couple of molds and now I decided to try my H&G #68 with it. I wasn't getting the fillout I hope I would and was getting alot of rejects. Mold is 4 cavity, PID set to 750 degrees. NOE mold guide setup installed. Mold up to temp. Not much in the way of wrinkly boolits, but more of the first band not filling out. I even got the mold so hot, the pour wouldn't solidify. I noticed on my NOE and Lee molds the sprue plate has individual sprue holes while the H&G has the trough. Never had a problem ladle pouring into it. Just seems more difficult with the H&G sprue plate. Anyone have any tips?

[oger]

Iron molds are different than alum to work with. Fill the trough as you fill the holes and try filling the mold faster, once you get it right you will find nothing works better than the H&G

[LenH]

Keep the trough under the spout and just keep the mold moving, just like oger said. The 4 cavity molds are easy, try and 8 cavity, those are beast.

[lightman]

I tilt the mold a little bit up at the back and start pouring in the first cavity, moving to the 2nd, 3rd and 4th. I usually have one long sprue doing it this way.

[Dusty Bannister]

I think that everyone has their own extra touch when it comes to multiple cavity molds. If you are not getting the bases well filled, you might be pouring too slowly, or the plate (heavy iron plate) is not hot enough.

I have tried two methods of filling the mold cavities and one might be helpful to you. With the Lee molds, no trough, I start at the far end of the mold, tilted slightly down so any run off goes off the end and not into the next cavity. I poured in a steady stream and moved the mold to the next holes until I had completed the row. This often resulted in rounded bases and lighter weight of the casting. I then tried the same position but did the stop and go at each cavity which directed the flow into the sprue hole more consistently and the bases were much better. And this also resulted in one single long sprue when cut.

Perhaps the continuous flow is actually blocking the venting of the cavity as you move the mold under the nozzle of the pot and the problem with the bases is the result?

[Dale53]

I have a couple of RCBS Pro Melts. I almost exclusively use multi cavity molds. I have the top of the mold about 3/4" under the pour spout. I can regulate my pour rate by leaving the adjustment screw loose to finger adjust. I have the lead stream just a bit faster than than "drip, drip, drip". In other words, a steady stream but not fast. I target the hole and let the weight of the lead falling center the hole. My theory is the weight of the falling metal insures fill out.

I pre-heat my mold on a solid hot plate. I heat to just under casting temp to ovoid over heating. It takes one to two casts to get my mold up to temp. I cast between 700-750 (depending on alloy). My "standard" alloy is WW's + 2% tin. This level of tin helps to insure fill out.

I don't have a Lee pot so some of the details may or may not be pertinent.

FWIW
Dale53

[Dragonheart]

I run 2 H&G 4 cavity molds simultaneously at 800-825 degrees (alloy Thermometer checked) for perfect fill out and very uniform weight out of my old Pro-Melt. I pour as fast as my molds can take it. I have no wait time, no lead smears and faster production. The guys at H&G knew what they were doing as they are the best molds I own and I own a lot of molds. The long trough helps get the mold up to temp and keep it that way due to the extra surface contact. Not to mention easier gathering up the cut sprues. One day when I have a few more projects finished I think I will mill a trough into my NOE molds or just make a thicker sprue plate with a trough.

[Conditor22]

You could try adding more tin. I'm averse to casting at temperatures over 700° even though the lead flows better.- the hotter the alloy + the more the boolit will shrink when cooling (lead expands more the hotter it gets) Unless you have oversized molds or coat you boolits you could end up with undersized boolits.

I preheat my molds to 400° and pressure pour my first few boolits to ensure the cavities are hot. In multi-cavity molds, I like to alternate the fill direction to maintain an even heat in the mold.

[Dragonheart]

Conditioner is right a hotter alloy will make a small difference in bullet size. I don't have a mold that will drop an undersized bullet and wish I had molds that would drop bullets where less metal had to be moved.

I do PC and size all my bullets approximately .0015" over my groove measurement taken from a slug fired through the barrel. In my limited testing I have found no accuracy advantage in sizing a bullet larger. Uniformity is the key to accuracy and if you are getting inconsistent fill out so goes your accuracy. I own about 12 H&G molds and the weight consistency of the bullets is amazing, especially when one considers these molds were made long before all the computer controlled equipment of today.

[Sig556r]

To add to what the gurus already stated, check your flow rate, if nozzle is restricted clean it with paper clip & run the lever screw back & forth to get any dirt blocking the flow out. At temps of more than 700F, you should have nice smooth flow not drips.

[Tmaloy]

Thanks for the tips gents. I think the first thing I should do is a thorough cleaning of the mold, and then smoke it. It's been a while since I used it and just took it out of storage. I also noticed that since I am only a beginner and starting to use the Lee bottom pour beginner I need to make sure the pour is going directly in to the sprue holes directly in the mold.