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View Full Version : Mould guide for soft nose caster.



44man
08-22-2006, 12:40 PM
I got out my pot and found it has a lot of room for some guides. I was looking at my other pot and thought there was a shortage of room. I made it out of oak and a piece of aluminum from a storm door. I used two screws placed as stops for the mould which is a 2 cavity. Push against one and drop lead, pull back against the other screw and drop lead into the other cavity. It should even out the level in the mould. Now I need to figure a removable stop for my single cavity moulds. No need to look underneath the pot.

44man
08-22-2006, 12:42 PM
I am also going to try a 20 to 1 mix for the nose instead of pure lead. Should flow better and make a nicer joint.

44man
08-22-2006, 03:01 PM
I just cast some to see what happened. There is no difference in the joint, it being more open on one side. I use a ladle so I wondered about the bottom pour. I had to clean out the spout to get the best flow. NO GOOD, the base will not fill out. So I held the mould tight against the spout for head pressure. Bases were good but the joint was the same and maybe a little worse. I then tried pouring from the ladle instead of holding them together. Bases not filled again. I will never understand how anyone can use a bottom pour or pour from the ladle and get good boolits. Both of my pots are running wide open instead of the 750 to 800 degrees I usually cast at. Anytime the lead has to span a gap to the mould, the boolits suck. Same thing I have found in 51 years of casting. The larger the boolit, the worse it is. The only way to cast is to have the ladle or pot spout and mould together and hold it there for some time before tipping them apart. The only boolit that will fill from a pour is a round ball. Lead can't go up hill to the corners of a base unless pressure is there.
I have to wonder if that is not the reason some guys can't get good accuracy from cast. Commercial casters must have pots that get a whole lot hotter then what we use. The bottom pour spout must be larger too so lead flows with more pressure. The little trickle from my Lyman and Lee pots are pathetic. I will stick with the ladle! I want lead into the mould RIGHT NOW, not a little stream or a trickle at the edge of the sprue hole. No wonder there are so many posts about bad boolits! A sprue cutter with a large hole and a ladle with a large hole, tipped up together and held in place still makes the best boolits.
Yeah, I will get static but how many rejects do some of you get? I might, I repeat, might, get one in every 300 boolits that doesn't look right if I had to stop and pee.

Bass Ackward
08-22-2006, 03:23 PM
Ah come on now. Tell us what you really think? :grin:

But let's get serious here for a minute. In another post, I thought that I read that your first attempt at these bullets shot better than the one mix bullets of perfection, parting line and all. Are we getting just a mite ..... picky? How are you going to keep track of these bullets if you eliminate the line?

Personally, I think that you simply have a pot bias. The real problem is the mold maker not putting in enough ventilation that it takes the weight of a laddle sprue to get fillout.

Gosh darn trainee mold makers. :kidding:

BruceB
08-22-2006, 06:17 PM
Heh, heh...everyone's just the same, except when we're NOT!

I'm a bottom-pour feller from a loooong ways back...I believe my wife gave me my first Lyman furnace in the late '60s, and it's been bottom-pour for me ever since that happy day. I plumb wore that sucker out, and it was finally replaced fifteen-or- so years back with my current RCBS Pro-Melt.

Sure is strange, how our results differ so drastically. I have little to no difficulty getting bullets to fill out perfectly, and even big bullets present no problems. By "big", I mean the 500-grain .45s, 350-grain .416s, and for a while I cast a lot of 560-grain .50s. Typical weight variations are very small....like less than one grain extreme spread on 416-350s and 457125 500-grainers. I do still believe that casting as hot as I do (870 degrees) is a great aid in correctly filling-out the boolits.

Also a big difference in our methods is my practice of using an air-drop gap of as much as an inch between spout and mould. On occasion I do "pressure-pour", with the sprue plate right against the spout, but mostly not.

To avoid that "joint" in the softpoints, heat the mould right in the pot, just as hot as you can get it. Doing so keeps the two alloys liquid for a long time, and the bullets are the crispest, best-filled-out bullets I may ever have seen. My whole purpose in researching the cast softpoint was to ELIMINATE that joint, and the possibility of having the bullet come apart on impact. Heating the mould to melt temperature has accomplished this, and results in there being NO JOINT.

Sheesh, I'd hate to have to go to using a ladle at this late date. But, we all know what they say about opinions, right????

Buckshot
08-23-2006, 01:48 AM
.............You can easily drill the spout larger, at least on the Lee 20lb pot. First hole I drilled just didn't look like much of an improvement, but by golly the SECOND one I drilled provides a veritable flood :-). A bit too much of a good thing. I wouldn't even attempt to try and pour 22 cal slugs with it, and I have it set up to BARELY lift off it's seat now!

................Buckshot

AZ-Stew
08-23-2006, 12:23 PM
44man

I'm with BruceB and Buckshot, but you've also touched on part of the cure.

I use bottom pour with a gap, like BruseB, but as did Buckshot, I've modified the pour spout of my 10# Lee pot so it has a larger hole (sorry, I did it 25-30 year ago and don't remember how big I made it). In addition, after reading a magazine article many years ago, I also modified the sprue plates on my larger caliber moulds. I used a machinist's countersink in a drill press and bored them out to leave a 3/16-1/4 inch hole for the lead to pass through. The burr on the bottom of the sprue plate was filed/stoned off to leave that side of the plate smooth and flat.

When I cast, I just turn the temp up enough to get fillout, which is never max temp on my pot. I leave a GENEROUS sprue puddle on top so metal can continue to get sucked through the hole and into the bullet base as the alloy cools and shrinks. This eliminates voids in the lower sections of the bullets and produces bullets with very uniform weight. This is similar to the effect you get by holding your ladle on the sprue plate for a few seconds. I allow a couple more seconds to ensure that the sprue is solid before cutting to avoid lead smear on the bottom of the sprue plate and the top of the mould blocks.

Good luck and keep us informed of your progress with the soft nose bullets.

Regards,

Stew

AZ-Stew
08-23-2006, 01:11 PM
Addendum to my last post. The last paragraph need mor info:

When I cast, I just turn the temp up enough to get fillout, which is never max temp on my pot. I leave a GENEROUS sprue puddle on top to slow cooling in this area and to provide a supply of molten alloy so metal can continue to get sucked through the hole and into the bullet base as the alloy cools and shrinks inside the mould. This eliminates voids in the lower sections of the bullets and produces bullets with very uniform weight. This is similar to the effect you get by holding your ladle on the sprue plate for a few seconds. I allow a couple more seconds to ensure that the sprue is solid before cutting to avoid lead smear on the bottom of the sprue plate and the top of the mould blocks. Bear in mind here, the larger holes in the sprue plate do two separate things: 1.) they improve flow to ensure complete mould fillout and produce square corners, and 2.) they allow alloy to be pulled into the mould during cooling to eliminate internal voids in the bullets. The metal being pulled into the mould during cooling does not fill the corners of the mould. They're already solid because they cool and solidify first. The center of the bullet base (assuming a base-pour mould) cools last, and this is where the shrinkage will occur during cooling because this area is still soft. If the sprue is too small, it will cool too quickly and air will be sucked into the bullet base around the sprue or through microscopic holes that will occur between the crystiline structure of the rapidly cooling aloy. This will cause base voids.

Regards,

Stew

44man
08-23-2006, 02:25 PM
Yeah guys, I realize that the bottom spout has to be larger and that is my problem. Even cleaned out, there is just a tiny stream and the boolit will start to set up before the mould is full. Sprues set up faster then they do with the ladle. I have to wait quite a while when using the ladle for the lead to set. I was running the pots over 900 degrees and it didn't help. I left the largest puddle on top that I could. I never messed with the spout because I always use a ladle. The strange thing is that even pouring from my ladle which has a large hole, the bases did not fill and no, the mould is not lacking vents, I made it.
I think the answer is mould temperature because making a two part boolit slows the pace. If I cast regular boolits too hot I get frost and whiskers but I can't even get a frosted boolit using the two pots. I notice the pure lead sets REAL fast. I don't think the little pot gets as hot as it should, I never used the thermometer in it. I just cranked it wide open. I know it makes great boolits with the ladle.
Maybe a level stand with a torch under it to heat the mould after the nose lead is dropped would do it. I would need a lock for the handles.
The boolit does shoot good to 50 yd's but out at 100 it starts to open groups. I would like to have an even seam or no seam between the nose and base. I would also like an even distribution of nose lead because it weighs different then the hard alloy.
I can't put the mould in the pot because it is too big.
The soft nose pot never throws the exact amounts either, some boolits have a larger nose then others. I need a small scoop.
I tried the 20 to 1 mix and it looks the same as the pure lead so I will just save that lead for BPCR.
I might try a pot of pure lead on my plumbers furnace to raise it to 1000 degrees or so. That might keep the mould hot. I could hold the mould handles on a level stand, pour the hotter lead and pour soon with the ladle. That way I don't have to move the mould and shift the lead. The seam is not too important as long as it is even all the way around, mine are crooked and more open on one side.
This is just for fun anyway! If I don't get what I want, my regular alloy with the huge meplat works just fine on deer. I would just like to see the results when I hit one. Too much meat damage and the soft nose will go away.
How about one of you coming up with a ladle that would inject just the right amount of pure, then follow up right away with the hard stuff. Maybe two spouts and two chambers. Or a spout with a gate! Fill the front of the ladle from a dipper of pure, then after pouring it, open the gate. HEE, HEE, now I got you thinking.

Bass Ackward
08-23-2006, 02:45 PM
1. and no, the mould is not lacking vents, I made it.



2. I might try a pot of pure lead on my plumbers furnace to raise it to 1000 degrees or so. That might keep the mould hot. I could hold the mould handles on a level stand, pour the hotter lead and pour soon with the ladle.

3. How about one of you coming up with a ladle that would inject just the right amount of pure, then follow up right away with the hard stuff.


44,

You made the mold? I....I....I....I didn't know that!!!!!! :grin:

Now. Life can be pretty simple. Use you plumbers furnace to heat and melt the lead nose before you fill the base. I would cheat. Use a muzzle loader ball of a certain size, that satisfies you, so the quantity of lead is always the same. I use a 30 or 32 ball for 44s. You can use the tourch to help heat the ball with the plate open. Since you need to laddle, close the plate and use a level hot plate to rest the mold on while you laddle in the rest. This way it doesn't lose heat too fast on the nose.

Satisfied? There is a $10 charge for that information :grin: Pay me when that other guy pays you for your bullets. :grin:

44man
08-23-2006, 04:04 PM
OK Bass, I will try it. But you didn't make me a ladle for the $10!