base not filling out(driving me nuts)

[RU shooter]

I have a new to me lee 309-150 FP and no matter what I do I cant get complete base fill out ! Yes Its clean, vents are clean ,the top edges of the blocks have been slightly beveled. I've tried different temps, different alloys even 50/50 ww and lino with babbit added gives less than perfect results! Whats next? what havent I tried or am doing wrong? I am laddle pouring and never had issues with my other moulds no matter how I pour as long as the alloy ends up in the sprue hole.Maybe open up the sprue holes alittle? Help


Tim

[fredj338]

Have you tried holding the ladle tight against the sprue plate? This is how I cast most molds & it almost always gives complete base fill out. Maybe more lead in the ladle will help too.

[462]

My Lee moulds like the alloy to be HOT. I turn the thermostat to the maximum.

[SciFiJim]

I had similar issues with a TL358158 caliber mold. The solution I found is after pouring a generous sprue, jiggle the mold slightly while the sprue is still liquid. I have also heard to bump the bottom of the mold on a table slightly while the sprue is still liquid. Both methods help the lead to settle into the cavity for better fill out.

[R.C. Hatter]

You might check the sprue plate to make sure it's not too tight, which can hinder base fill-out. Also, you can try increased alloy heat, the addition of some tin, and leaving the ladle in contact with the sprue plate longer which allows the base of the bullet to draw more metal as it cools. Sometimes, a slight bump of the hinge pin (not the mould blocks) on a hard surface such as a piece of 4"x4" while the ladle is still in contact with the sprue plate will aid in fill-out.

[geargnasher]

I use a bottom pour with the Lee moulds, even then it's hard to cast fast enough to keep them hot. Do what 462 and fred' said, get a little gravity pressure on that mould, and use a full ladle. When your start getting spikes on your bases from the bevelled blocks you know you're getting good fillout.

I'm assuming you're using enough tin in your mix?

Gear

[RayinNH]

Have you tried holding your tongue off to the side while pouring? Actually I've usually found it to be a heat issue, try a little hotter...Ray

[mooman76]

Make sure you are leaving a good size puddle on top the sprue plate when you pour. That does help. Heat too could be a factor. I recall a few people here saying they couldn't get the bullet closest to the handle to fill out well. I never had that problem until recently and found that loosening the sprue plate helps in those cases. One I had to loosen to the point that you would think it was too loose but that is what it took to get good fill out at the base.

[O.S.O.K.]

You say you've tried all kinds of temps - I find that I get best results at around 850-900.

[RU shooter]

Thanks for the ideas,I have the sprue plate pretty loose already its adjusted as on my other moulds. I generally pour with a 1/4" or so between the laddle spout and the hole(always worked well with the other lee moulds?)I'll try right up in it I guess, Good idea on tapping the mould while the sprue is still liquid I'll give that one a go too.Same with the temp.But I never had to run any of my moulds that hot before for good results. again thanks all.

Tim

[docone31]

Tim,
Heat soak the mold prior to casting.
I let my mold sit in the melt for a time before I cast my first boolitt.
If you have not yet, soak it in mineral spirits for a few days. Do not smoke the mold.
I try to cast with a six second delay in the sprue freezing. If it is faster than that, I let the casting minus sprue, sit in the mold. That helps the heat. If it takes longer than six seconds, let the mold cool just a bit.
Once you have the mold at the right temp, you will notice the difference.
My first few castings with Lee Molds sucked. Actually quite a few. Once I dialed that technique in, they are great!

[Ben]

RU shooter :

I had the same thing happening to me on a .30 cal. Lee mold a few days ago. I finally corrected the problem with a couple of HOT soapy water treatments with a tooth brush on the hot mold. If there is a millionth of a tiny micro gram of oil in that mold, you'll probably never get good fill out. You often have to clean, re-clean, re-clean, etc. until you finally have a mold that is 101% oil free.

I then took a fine cut jeweler's file and cut a TINY bevel on the tops of the mold halves to allow a little more air to vent at the base of the bullet. Presto........perfect now.
( go easy with this last treatment as you could end up with whiskers on the base of the bullet if you over-do the bevel treatment process )

Ben

[Marlin Hunter]

I had similar issues with a TL358158 caliber mold. The solution I found is after pouring a generous sprue, jiggle the mold slightly while the sprue is still liquid. I have also heard to bump the bottom of the mold on a table slightly while the sprue is still liquid. Both methods help the lead to settle into the cavity for better fill out.

+1

I tap the black part of the handle that mounts to the side of the mold with the wooden dowel I used to open the sprue plate. It I get a tapping rhythm going, it is like counting out seconds for the sprue to cool. I usually tap 10 times, then open the sprue plate.

[dardascastbullets]

Hi RU,

I believe your problem lies in the metal that you are using. You stated that you used '50/50 ww and lino with babbit added'. You actually should have casted your bullets with the linotype (assuming that it is actually linotype with no stray metals). You would have realized excellent results! Mixing the linotype with wheel weights actually contaminated your great linotype with stray metals. Now you may never realize great results with that metal. And the babbit is a very bad choice to use as a casting alloy. Why? Babbitt contains a goodly amount of copper which provides a lubricating property for the bearings that it is intended for. The copper is a stray metal that will cause rounding (in complete fillout). Hopefully, you did not mix this in with your linotype. Hopefully, you have some linotype remaining that you can cast some great bullets with.

[geargnasher]

Hi RU,

I believe your problem lies in the metal that you are using. You stated that you used '50/50 ww and lino with babbit added'. You actually should have casted your bullets with the linotype (assuming that it is actually linotype with no stray metals). You would have realized excellent results! Mixing the linotype with wheel weights actually contaminated your great linotype with stray metals. Now you may never realize great results with that metal. And the babbit is a very bad choice to use as a casting alloy. Why? Babbitt contains a goodly amount of copper which provides a lubricating property for the bearings that it is intended for. The copper is a stray metal that will cause rounding (in complete fillout). Hopefully, you did not mix this in with your linotype. Hopefully, you have some linotype remaining that you can cast some great bullets with.

I must respectfully disagree with your assessment of the copper in babbit being ruinous, unless the copper concentration is like 3-4% of the total casting alloy (which it could be if a copper-based babbit alloy is used in high concentration). I'm not saying you're wrong, just that my experience has been different.

Most of the babbit I've seen is tin-based, some with antimoy/lead added and some with only copper, there are, of course, a bazillion different kinds. I've used a known-content copper-containing babbit for up to a total of 2% copper in the finished alloy, and found it casts and shoots very well. Takes plenty of tin and heat to make it work, though, and that's probably why RU is having trouble: mould not hot enough and not enough total tin in the mix.

One of these days I have planned to see just how much copper a boolit alloy can handle in hopes of garnering some of the gilding-metal lubricity in a low-temp and castable alloy. Too bad zinc makes casting a pain, it sure helps lubricity in copper j-word jacket alloys (bronze, technically).

Gear

[RU shooter]

The Babbit content is very low in this batch 1 maybe 2% total content ,approx. 80% lino balance is WW. I have used this in other moulds with no issues ,I;ll be firing up the pot tonight to try some new methods after another through cleaning .I'll post results as to the out come.


Tim

[RU shooter]

I tried some of the suggested tricks tonight, I tried jiggling the liquid sprue, tapping it, cleaned twice , about the only thing that seemed to work was having the laddle spout right up close to the hole,seeing that I dont normally pour this way it took some trial and error but good fill out occurred doing it this , So I guess its true every mould is a different animal and has its little quirks to perform at its best. again thanks all for the tips .

Tim