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marvelshooter
03-14-2017, 09:23 AM
How much trouble am I asking for by considering this? I want to shoot the same boolit with and without gas checks and buying a 4 cavity mold with 2 of each is one option. I know I could just cast all 4 but may not want or need to. Thanks - Dan.

Bent Ramrod
03-14-2017, 10:15 AM
Get the cavities you want to cast most often on the front end of the mould, away from the handles. You can then tip the mould down slightly so the molten metal doesn't run backward into the other cavities. At least, not too often.

Using a bottom pour pot and a mould guide will generally not expedite this process. An aluminum mould is indicated if a long casting session is desired.

When using the back cavities, more nuance and technique will be needed, and many partial castings will have to be culled out of the pile.

I find even two cavity moulds with different design cavities are less practical than they seem in theory. Like the servant with two masters, I wind up liking the one cavity and despising the other. But I get them both. My worst is a three-banger with a hollow point cavity in the middle. No way I separately cast those.

Generally, I wind up going for a smooth casting routine that fills both or all the cavities, and keep the unwanted ones for either the remote contingency or remelting. YMMV.

JonB_in_Glencoe
03-14-2017, 10:16 AM
I have a couple NOE 2 cavity molds (both rifle molds), where one cav is GC and the other is PB.
I do cast with both cavities, all the time, when I cast with those molds, then separate them afterward when I sort out the culls.
The main reason/thought behind that, is temperature control and boolit consistency. Now I haven't tested that theory, it is just my gut feeling.

dragon813gt
03-14-2017, 10:22 AM
The combined GC/PB molds are all I really buy from NOE anymore. I cast all four at once. Separate at the end and throw the type I don't want back in the pot. While it may work to cast just two cavities you're going to change the characteristics of the mold by doing this. I'd rather not fight the mold and sort at the end. This takes little time.

R.Ph. 380
03-14-2017, 10:23 AM
WHY???

Sent from here to there by me using smoke signals

dragon813gt
03-14-2017, 10:29 AM
WHY???

Sent from here to there by me using smoke signals

Did you read the second sentence in the OP?

R.Ph. 380
03-14-2017, 10:35 AM
You bet, waste of time, money,effort and inefficiency.

Sent from here to there by me using smoke signals

marvelshooter
03-14-2017, 11:37 AM
WHY???

Sent from here to there by me using smoke signals

Partly because a 4 cavity mold is a lot cheaper than two 2 cavity molds and partly because it's all NOE has right now. It was just a thought.

runfiverun
03-14-2017, 12:14 PM
why not?
if you just want the gas check or the not gas check boolits there is no reason to cast them all.
the heat will soak in around the cavity's your using enough to make good boolits.
if you need to just cast the third cavity every now and then.

Shiloh
03-14-2017, 03:20 PM
There is a pic floaing around of a 4 cavity mold with two cavities hollowpointed. You have a choice.

Shiloh

country gent
03-14-2017, 06:27 PM
It can be done easy enough buy just filling the cavities you want. The only problem may be getting and keeping the blocks up to temp only filling 2 of the four cavities due to more mass in the 4 cavity blocks. Aluminum will be lighter and bleed heat faster brass is heavier but will hold heat better. I believe doing this pre heating the mould on a hot plate will be a big benefit. As will casting at a fast pace will help also.