RCBS-300-swc-gc

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Last Post 05 November 2007

Standard Member

Southern Man posted this 13 June 2007

Hello out there,I still have'nt found washers for my H&G 224,If any one collects these H&G mine are real nice and I"d take a loss and let them go for $100.00.Any way guess it's time to move on to something else.My bases are coming out rounded on my RCBS 300 swc-gc unless I pressure pour from bottom spout.then they come out finned.Then I tried ladle pourin and the bases filled out but there wiskered.I've tried diffrent alloys,diffrent temps,and adjusting the sprue plate from one extreme to the next,all with the same results.What few I've got that were good,about 20 to 30% letting the alloy pour about 1/2” then using hornady gas checks I shot my best hand gun groups ever with my freedon arms and 10 grn. Unique..300"@ 80 ft. So I would realy like to get this thing working right.By the way if there uniform, how critical is it that the bases be sharp as long as Im using gas checks.thanks for your help ,Southern Man

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454PB posted this 13 June 2007

That sounds like a sprue cutter problem. I would guess it's warped some, or has a burr on the bottom where it hinges. Try laying it on a known flat surface and see if it's absolutely flat.

I had a Lyman mould years ago that acted the same way. I tweaked the sprue cutter, then filed it flat and polished it and the problems went away.

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CB posted this 13 June 2007

If working over the sprue plate doesn't work I've taken to milling an .080 deep cavity into the top of the plate on RCBS moulds I recut because of whiskering using a ladle and it works like a champ. Think of a LBT design and you'll get the idea. Just hold the mould and pour the alloy in the cavity letting the excess run over the front back into the pot. Veral's plate design is ingenious and all moulds should use something similar if you ask me.

Pat

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Standard Member

Glen posted this 14 June 2007

Sounds like the base isn't very well vented. Make sure the top couple of vent lines aren't plugged.

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Southern Man posted this 15 June 2007

Hey Guys thanks for the help,I checked the sprue cutter and it was flat,but I checked a Lyman that I've been having trouble with and thats what's wrong with it.I've never seen a LBT so I do'nt realy know what you mean Pat,I would like to know if you dont mind giving me some more info.When I first started using this .45 rcbs 300 swc-gc, the bullets would'nt hardly drop at all.So the next time I used it I sprayed it with a release agent from Midway.What Glen said about the venting made me think I mat have stopped it up with the release agent.So today I cleaned it with Gunscrubber,let it dry then smoked it with Diamond brand kitchen matches.Then started casting withit and a H&G.30 cal. Using lynotype and the bottom pour spout,I had my best casting session yet."started casting in Feb” The bullets filled out great and look good from both moulds.The two ran good together at 740 degrees.After I started seeing those sharp silver bullets I could"nt stop and used about 40# of lyno.Southern Man

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Standard Member

CB posted this 21 June 2007

Yup I have the same trouble. I like them pretty shiny bullets too! Have a hard time stopping.

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Standard Member

Lloyd Smale posted this 28 June 2007

What i find with some big molds and using alloys rich in tin is that it is a venting problem. Ajust your bottom pour to pour at a rate the doesnt plug the spruce plate hole while filling to allow air to escape and make sure you are leaving plenty of extra lead on top of the spruce plate.

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CBA Member

WRDSMTH posted this 30 October 2007

When I have a problem with a bullet not filling out, assuming the mould and lead are hot enough, I sometimes try turning the mould sideways and pour against the seam of the mould. It is a bit of a pain, but often works.

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CB posted this 30 October 2007

.My bases are coming out rounded on my RCBS 300 swc-gc unless I pressure pour from bottom spout. By the way if there uniform, how critical is it that the bases be sharp as long as Im using gas checks.thanks for your help ,Southern Man

Southern Man, Good that you have found the trouble and the mold is working. However, I didn't see that anybody addressed your last question which is to me an important one since we all eventually have other molds- alloys that sometimes produce rounded bases.

The answer is that sharp bases aren't critical at all for most applications. I have shot lots of CBs with rounded bases and have never been able to tell any difference in accuracy at least down to the one minute of angle level. Since it is unlikely that you are getting that kind of precision out of the 300 grain SWC-gc, don't worry about the rounded bases. If there is enough gas check shank for the gas check to crimp on to I don't think you will be able to tell the difference. Shoot them and have fun. Sometimes a person can go crazy trying to get “perfect” bullets and most uses don't require them for the kind of precision most of us get even with a pretty good rifle.

If you were trying to set national records, my answer would be a little different.

John

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CBA Member

fa38 posted this 30 October 2007

To make the base fill out on several moulds that I have I take a 2” by 8” Norton India stone and put a slight bevel on the top of the mould blocks. Gives you a vent line under the sprue plate.

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Standard Member

Southern Man posted this 01 November 2007

Hello , Guys , I have'nt logged on for a while,been getting ready to go to Wyoming for a few months .I had a great hunt, killed a good buck Antelope, a good buck Mule deer , and a doe antelope with that RCBS 300 SWC-GC from my Freedom Arms .454& some smaller critters with my Gary Reeder .454 conversion & same bullet, so Thanks for all the help.fa38 I would like to know more about what you do with the stone. Do you stone up to the edge of the base or stop short? Thanks again Southern Man

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CBA Member

fa38 posted this 05 November 2007

Where the mould halves part I stone the entire part line surface. I don't get any wiskers from this top vent line either.

I recently purchased a RCBS 32-098 SWC double cavity that had a base that would not fill out unless the sprue plate was very loose. I could not stand the way it flopped around so I put this vent line on it and snugged the plate down so that it would barely move of its own weight. The bases now fill out very well.

This mould has to be one of the best casting moulds I have ever owned. Lots of bullets well filled out in a very short time. I think about 490 in about an hour and an half.