Improved Sprue Plates... Any Interest?

[Cap'n Morgan]

What I would like to see is a small dam around the sprue holes so that I don't get 'runoff' of alloy into my quench bucket.

Maybe something like this:





I was tired of constantly spilling molten lead all over the mold when bottom pouring, and at the same time wondering if a large sprue puddle (the casting term is "dead-head") would eliminate shrinking voids in the bullet base and improve filling.

The system works great; There's plenty of warning time between the filling of the cavity and the sprue reservoir running over (the dead-head weighs about 400 grain) There's absolutely no splatter - even if the stream of lead is off center. The combined weight of the sprue plate and the dead-head prevents the sprue plate from lifting due to the pressure - which sometimes can be a problem with a large bullet/small sprue plate like this one-cavity mold.

The best part of it is that it has turned a somewhat stressing task into a zen-like experience You watch the silver flow raising at a steadily pace in the sprue plate until you cut the flow, then you watch the lead solidifying for five - maybe ten seconds before cutting the sprue and dropping a flawless boolit

[Doby45]

Dats nice right there, real nice. Looks like a TIG weld and if I had a single cavity rifle boolit I would want the exact same thing.

[Bloodman14]

Cap'n, that's exactly what I'm talking about! Jim, can you make that happen? I will need a few made up.

[JIMinPHX]

Either the Captain has a real steady hand with the tig torch, or else he has a genuine tubing welder. That is a beautiful bead if that's what it is. Alternately, he may have machined that.

I don't have a tubing welder & my tig is in storage back east, so I can't weld anything that pretty.

Let me think about it a little though & see what I can come up with.

[Cap'n Morgan]

You're right, Jim, I machined the sprue plate from a bar of steel - easy to do when you have access to a CNC mill - but welding a tube to a sprue plate would not be that difficult. Just make sure the inside of the tube is tapered to prevent the dead-head from sticking.

[Doby45]

That does make sense cause I was thinkin that was one gorgeous TIG weld, which could be possible but tedious. The machining of it is even more uber cool.

[JIMinPHX]

Just make sure the inside of the tube is tapered to prevent the dead-head from sticking.

I found that out when I machined deep sprue holes in my aluminum plates for Lyman molds. Even a short straight section would cause the sprue to get stuck.

[JIMinPHX]

That does make sense cause I was thinkin that was one gorgeous TIG weld, which could be possible but tedious.

I did some consulting work at a jewelry manufacturing plant about 12 or 14 years ago. They were making large quantities of ear rings out of hollow gold tube. They were rolling & welding the tube on site with progressive forming dies & a continuous process tig welder. We were able to get the welds so good that you could not see them. I've seen an automatic tubing welder leave a bead nearly that good too.

[JIMinPHX]

Cap'n, that's exactly what I'm talking about! Jim, can you make that happen? I will need a few made up.

What sprue plate did you want me to try that tall collar trick on? 6-hole Lee?

[a.squibload]

Maybe something like this:...

Dam, that's good.

I'm thinking that dead-head could be useful if you make it fit a 12ga wad!
Maybe a ring inside the collar like in a measuring cup, for consistent size.

Would there be a problem with warping the plate if the collar was to be welded on?

[JIMinPHX]

I'm thinking that dead-head could be useful if you make it fit a 12ga wad!

That's not a bad idea. I wonder what you would do for load data though.

[excess650]

I'm game for one or more of the Lee 6 cavity type plates in steel and with conventional sprue holes vs the trough. My smallest are 30cal, so whatever is standard will work for me. I would prefer to turn the mold around so that it operates like a conventionally worked sprue plate vs Lee's cam operated design.

I'm sure these would be beneficial for pistol bullets, but I have several rifle molds that I'm not getting along with, and I'm sure a replacement sprue cutter of conventional design will solve the problem.

[excess650]

That's not a bad idea. I wonder what you would do for load data though.

12ga work at relatively low pressure, and Lyman's shotshell handbook had a fair amount of slug data in it. Their's was for slugs in wads in addition to Foster type slugs, but I interpolated their data and loaded full diameter slugs in my 870. I think that NEI "bullet" weighs 580gr, and casts .735". I used Blue Dot because it seemed to be the powder to use for 2-3/4" mag loads. I used nitro cards under the bullets to attain the correct internal volume, and then roll crimped. Recoil was pretty brutal, but no issues with pressure unlike one of the factory loads that I had tried.

Using those "deadheads" in wads shouldn't be any different that undersize bullets in sabots. It may require trying various wads for height, and possibly trimming petals and adding nitro cards to build the column, but shouldn't be problematic with slow powders.

[Bloodman14]

Jim, if that could be done on a Lee 6-shooter using a steel sprue plate, THAT WOULD BE AWESOME!! Also the Lee single and double cavities. I would gladly send you my Lee 6 sprue plate for a pattern if you need one, but be aware it has been modified/improved. I also wouldn't worry about the trough; what about a piece of strap that is formed to fit around all the holes at once, thereby replacing the trough with an ingot-looking sprue? I just can't see welding individual tubes to make 'dead heads' (wasn't that the name of a fan group?).

[leadman]

My recent 6 hole Lee molds have a steel insert in the mold for the pivot screw.

Jim, I have some Lyman 4 cavity molds if you need to look at one.

[JIMinPHX]

Jim, I have some Lyman 4 cavity molds if you need to look at one.

That's good to know Mark, & thanks for the offer. I should be back in town tomorrow. Hopefully, the jet lag will wear off enough by Monday or Tuesday to let me get a few things knocked off.

[JIMinPHX]

Is this what everybody's 4-cav sprue plate looks like? Or are there other versions?

[Bloodman14]

Lee 6-cavs use a cam-type plate; their 1 and 2 cavs use a plate similar to your drawing. NOE uses a similar plate, too.

[excess650]

Is this what everybody's 4-cav sprue plate looks like? Or are there other versions?

That's what a Lyman looks like, and IMO, the 6 cavity Lee should look similar. With a conventional sprue plate the mold could be turned 180* in the handles to operate like a normal mold.

[JIMinPHX]

I'm looking for confirmation that all the Lyman 4-cav sprue plates look like the drawing in post #97. I've got the 6-cav Lee plates figured out. I only managed to get my hands on one 4-cav sprue plate to measure so far & have been coming across some rumors that there may be variations in the dimensions on 4-cav plates depending on how old the mold is. I'm trying to find out if that is the case or not.

Thanks,
Jim