PDA

View Full Version : Directing lead stream



currahee1911
05-02-2013, 11:32 PM
Hi,
Having difficulty filling my new Accurate Mold (230 gr. .452). Have to hit the hole dead center or it will not fill completely. Using RCBS Promelt.

Any tips on how to aim that stream, angle seems to vary during melt.

Thanks,
C.

SciFiJim
05-03-2013, 12:49 AM
You might try pressure casting. That is placing the sprue plate hole directly on the pour spout and then letting the stream flow. After the cavity is full, give it a 1 or 2 count and then lower the mold to pour a sprue on the sprue plate. The pressure of the lead above will sometimes correct incomplete fill out.

runfiverun
05-03-2013, 01:41 AM
might try and adjust the flow so it comes out faster.

hermans
05-03-2013, 04:59 AM
I had the same problem initially with my 4 cavity brass mold from Accurate. Once I got the mold up the the right temperature, it filled out properly, even with the stream coming down slowly.

RickinTN
05-03-2013, 08:31 AM
Tom's molds have a thicker sprue plate than most molds I've worked with. Get the mold/sprue plate up to temperature and I think you'll find your problems go away. I've found that just like any other mold you have to find what that particular mold "likes".
Good Luck,
Rick

Mal Paso
05-03-2013, 11:09 AM
Try more light. This is a Lee and I used an LED spotlight reflecting off the shiny bottom of the pot to index the molds. If the RCBS pot bottom isn't shiny a piece of aluminum could be attached. The better I hit the hole the better the boolit.

currahee1911
05-03-2013, 02:26 PM
Thanks, fellas,
Next batch was better, good tips.
Cordially,
C.

Cane_man
05-03-2013, 04:58 PM
had a similar problem with a new accurate mold, i had to adjust the stream on my bottom pour to slow down then it would fill very well... too fast and the lead would collect at the top of the sprue and fill out was terrible...

Mk42gunner
05-03-2013, 08:56 PM
Any tips on how to aim that stream, angle seems to vary during melt.

Empty your pot and clean the nozzle.

Robert

Le Loup Solitaire
05-03-2013, 09:39 PM
The angle of the pour is going to depend upon whether the blocks are level under the spout or if the handles are higher or lower. Some folks like to set up a "swirl" in the cavity and claim that this results in a better cast bullet. Another factor that will effect the fillout is how tight the sprue plate is to the top of the blocks. If too tight then the plate may restrict the escape of air from the cavity(ies). The plate should be loose enough to allow it to swing free of its own weight, but not up & down sloppy. Yet another consideration is the size of the pour...if the diameter of the stream is equal to or is more than the diameter of the sprue hole then it "drowns" the hole and inhibits the escape of air trying to get out of the cavity. A pour diameter 1/2 to 3/4 of the sprue hole should be enough to fill the cavity and allow air being displaced by the lead to vent out. Pressure casting with the sprue hole held tight up against the spout works for some casters, but you have to know when to drop the blocks a bit to allow alloy to flow over the sprue plate and provide alloy to feed the base of the shrinking bullet...otherwise you may cause voids in the bullet base....they are usually off center and set up a condition where the base of the bullet is off center...result is one side of the bullet being heavier than the other and when it gets out of the barrel--yaw and wild shooting. Different molds have different personalities and as you try different techniques you should jot down what you are doing and the results of what you do so that you don't have to guess or fish around the next time you sit down to cast. It saves time and cussing. LLS

Iron Mike Golf
05-04-2013, 01:02 PM
It's weird and I surely can't explain it, but when using a Mihec brass mold (this has happened from time to time in 2 or 3 molds, usually when pretty new), sometimes I'll have a cavity that doesn't quite want to fill all the way to a sharp base. If I do a few pressure casts in a row, it seemed to fix the problem, pretty much for good, or until I over-lube the sprue plate and mold block. Must be some oil residue and a pressure cast forces lead on that spot and boils it off.

ku4hx
05-04-2013, 01:24 PM
I have a six cavity Lee 45 mold that very much prefers the lead hit the slope of the hole and swirl into the cavity; all the others don't have a preference. I just do what works. Since I have an adjustable mold support device under the pot's spout, it's simple (with a little practice) to center the hole.

Marlin Junky
05-04-2013, 02:01 PM
Do yourself a favor:

http://www.buffaloarms.com/Detail.aspx?PROD=160455&CAT=3900

MJ

detox
05-04-2013, 03:46 PM
Preheat your mould and sprue plate...i use propane torch. Also loosen sprue plate so that it swings freely and just lays on top... this will help vent mould better and produce a more square boollit base. Increase melt flow by adjusting screw. Leave a 1/4" gap between spout and sprue plate hole before pouring. Keep melt temp between 650-700 while casting

Lyman or RCBS ladle works verygood also. Cast uphill..starting at the boollit cavity closest to you and work out. Fill ladle half full then hold ladle against sprue hole and pour. Try to leave a little sprue puddle on top. Ladle casting is easier using single or double cavity moulds.