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78CJ
04-03-2006, 11:53 AM
I started using the Lee mold for the .458 caliber 405 grain bullet for the 45/70 as one of my first experiences casting. The first casting session I did not notice anything up with the bullets but the second time I tried to cast I noticed that one half of the mold was not giving me sharp edges on the lube bands. I tried cleaning the mold with brake parts cleaner and that did not help. I read the post about improving the Lee molds but was too lazy and not sure that this would help.

I sent the mold back to Lee and they returned it cleaned up and well smoked (more than I was smoking it), I though to myself maybe this was the problem.
I tried it again this weekend and am getting the same thing. The mold half with the sprue plate fills the bullet out well but the other half is giving me rounded edges, rounded enough that if the mold were rounded inside I would be able to see it.

I tried adding some 40 / 60 flux core solder to my 10# pot of wheel weight alloy. I added a piece about 2' long and it did not seem to help at all. I also varied my casting procedure by placing the spout right against the sprue plate, swirilling the lead, letting it drop a little, and nothing would fill out that side???

Does it really matter anyway?

Oh yeah, the other thing is that the rounded corners are very frosted.

I am almost to the point that I would like to find a fellow caster here in Michigan that I could send the mold to and have them try it if there is nothing obvious that I am doing wrong.

Thanks

Ryan

mooman76
04-03-2006, 12:26 PM
If it's frosted you melt is too hot. Turn itdown a bit. Have you tried holding your mould at an angle or level if you were angeling it?

44man
04-03-2006, 01:41 PM
Are you bottom pouring or using a ladle? Those larger boolits need some head pressure to fill. If you are just running lead into the hole from a height, they will not fill. Try holding it against the spout with the handle held up longer. If using the ladle, hold the ladle on top for a longer time.
Instead of too hot, you might be too cold and the lead is setting up before filling the bands. This is the usual cause. Better to be too hot anyway.
With the bottom pour, the outlet hole might have crud in it limiting the flow. This is a very big problem with the bottom pour.
The ladle is better for large boolits. Make sure you have a good amount of lead in it and hold it much longer then you have been doing. The mould and lead has to be hot.
To just tip up the mould and ladle and then tip the ladle away, right away, will not give you good boolits. HOLD THAT POSITION LONGER before tipping off the ladle.

montana_charlie
04-03-2006, 01:42 PM
The mold half with the sprue plate fills the bullet out well but the other half is giving me rounded edges, rounded enough that if the mold were rounded inside I would be able to see it.
Guys use different techniques for uncoupling the junction between ladle and sprue plate. When I feel my mould (being held upright with the ladle on top) is full, I just tilt the ladle enough to allow the remaining lead to leak out onto the sprue plate...and dribble back into the pot. It looks messy, but it's really not.

This method, and closely related variations of it, has the mould being held vertical while the ladle gets manipulated in a number of ways. By the time one is finished fiddling with the ladle, the alloy in the mould has probably solidified.

If you are joining the ladle to the sprue plate...tipping the mould upright to fill...then returning everything to the original horizontal orientation (to effect a clean separation of the ladle from the mould) you may be allowing some of the alloy in the mould to pour back into the ladle, leaving the block on top with too little metal to keep the corners full.
CM

78CJ
04-03-2006, 02:47 PM
I am using a Lee bottom pour pot, I have tried holding the spout right tight against the sprue plate hole but maybe not enough. I am going to clean the pot prior to my next session and I will work on the flow.

SharpsShooter
04-03-2006, 04:47 PM
78Cj,

I use a bottom pour for 458 boolits up to 550gr and would use it for larger ones if I had the moulds for such a beast. It would pay you to go over that mould as described in the lee-menting post. I have the Lee 457-450-F, and it would not cast a decent boolit until I went through the procedure and cleaned up the vent lines and polished the cavities. After that hour and a half chore, it casts a fine, well filled out boolit. I use a Lee 10 pound capacity bottom pour and crank it up nearly full blast. When I pour the boolit, the mould is resting on the base structure of the pot, nearly an inch from the pour spout.

Clean up those vent lines, smoke the mould heavily and crank up the temp. Frosty boolits are fine. If you want em to shine just wipe them off with a paper towel after they cool.

StanDahl
04-04-2006, 12:12 AM
Like you, my first attempts at casting were with this mould. I have always had a tough time filling the bottom of the bullet, which has a very fine rim around the bottom edge of the base. I didn't get much success until I tried pouring directly into the mould with a full bottom pour ladle, like the way 44 man and Montana Charlie describe. Even then, many rejects result. I should try to re-vent it too, and see if that makes it more effortless. Stan

Blackwater
04-04-2006, 12:13 AM
78, FWIW, I was recently casting some Lee C430-310-RF's, and had a similar problem. HAd done as you did, and used brake cleaner to degrease the mould. Usually works, but on this occasion, I had a long stint before getting bullets to come out well filled out, and then there was some rounding on one of the cavaties of the grooves, as you describe. Maybe this time, I'd used some lube/preservant/oil on it that the brake cleaner just didn't clean up as well as I thought? I dunno. All I can tell you is that I took it to the sink and cleaned it with soap and water, then with Comet, and as Sharps Shooter says, checked and deepened some vent lines, and deburred the mould cavaties very lightly, and the problem vanished after doing that.

FWIW?

78CJ
04-04-2006, 07:25 AM
Well, I guess the first thing I have to do is get off of my butt and work on that mold. Next step is cleaning out my pot. Then give things a try.

Another question I have is can you have lead too hot? I do not have a thermometer but it is on my list. I just can't stop and wait for a thermometer because this is too addicting!!!

Ryan

44man
04-04-2006, 08:27 AM
I cast at around 800 for most boolits, but if a mould does not fill the bands, I turn it up a little and work faster. A little too hot does not hurt anything and frosted boolits are good anyway. It just takes more time for the lead to harden.
Some moulds with cut vents will spit out whiskers if it gets too hot but they can be rubbed off too. Just reduce the heat a little until they go away.
With all the trials I have done with the bottom pour, I found everything needs to be hotter then with a ladle. A small piece of slag in the spout can mess up good boolit casting. If the lead is swirling as it comes out of the spout, it needs cleaned. There should be a strong steady flow.
I quit messing with it and only use a ladle. I can run a 20# pot without a single reject.
With the larger 6 cavity moulds, the bottom pour would be the only way to fill the mould. Just takes more work and time to keep the spout clear and flowing. I can clean the ladle in a few seconds and since I don't have big moulds, I will stay with it.
If you pour a boolit and see the sprue get sucked in as it cools, there is not enough heat and the mould is not full. You should only see a little shrinkage on the top of the sprue and for the best boolits--none at all, meaning there is no more room in the cavity. My sprues still have a rounded top after cooling.

Bucks Owin
04-04-2006, 10:47 AM
I'm with 44man, if it's "frost" you are seeing it's no big deal. It's pretty easy to get an aluminum mould hot in a hurry, especially with big boolits....

I cast that same 405 gr bullet for my .45/70 and have encountered no problems using 50/50 WW and lino FWIW....(And cast kinda "leisurely" if ya get my drift....)

Dennis :Fire:

BTW, good tip about the sprue 44man!

Pilgrim
04-04-2006, 11:19 AM
78CJ - Take everything you read with a grain of salt. EVERYTHING in casting lead bullets is related. Unfortunately, you have to find out what your technique will be to get good bullets. Remember, the whole process is mechanical so to speak, and temperature, mould venting (or not), Mould metal (aluminum vs steel vs brass), alloy, boolit size and type, ladle, bottom pour, phase of the moon and more all interact. When you find a technique that works for you, generally you can get every mould you own to respond to the same casting technique. Sometimes it just takes a bit of fooling around. I have moulds that demand to be smoked. Others hate being smoked. I recently bought a Mountain Mould mould for casting 9.3mm boolits. I couldn't get good bullets for squat for the first few sessions. Dan ladle casts, I use a bottom pour. Dan got good boolits out of it before he sent it to me. I had problems with fillout. I cleaned, and degreased, and smoked the mould, and ran the temperature up and down and did it all over again, and...well you get the idea. For some inexplicable reason, probably my casting technique, I need to have moulds that are well vented. I've seen moulds without any vent lines cast perfectly good boolits, but I have problems with them. The MM mould I have was beautifully made, but I (with some fear of screwing it up) carefully opened the vent lines. The first time I used an exacto knife and just ran it through the vent lines. Things seemed to get better, but not yet good, so I took a Tool & Die makers file (very very thin) and carefully (very gently removing next to no metal) opened the vent lines a smidgeon more. Eureka! Good boolits and very very few rejects. I suspect the majority of folks would get good boolits right from the get go with that mould, but not me. Anyway, a LEE mould is not a major investment, so don't lose much sleep over experimenting with it. When you get to RCBS, Lyman, Saeco, Rapine, and then the custom moulds (MM, NEI, and others) the cost of making a mistake go up, so do your learning re: mould modifications on the LEE moulds. BTW - I've only been casting for 30+ years, and I have yet to buy a thermometer. I figure its just one item less I can break, so I have yet to get one. It seems I'm always dropping something on the floor of the shop and I have an aversion to glass bits and pieces. I run the pot wide open (temp wise) and when the mould starts to get too hot (takes a long time for the sprue and cavity to set up) I back off the pot temperature a bit. One thing to remember is that just because the sprue has set up, doesn't mean that the alloy in the cavity has set up enough for you to cut the sprue. Don't be in too big a hurry to cut the sprue or you will get "tears" on the boolit base instead of a clean cut, and you'll also gt lead smeared across the top of the blocks. Anyway..long missive...sorry...FWIW Pilgrim

redneckdan
04-04-2006, 01:44 PM
If you want another michigander to giver a try, i'd be willing to. I don't have a gun to shoot the boolits but I could try casting it and I'll send the boolits back. I live in houghton, MI.