Sure-Fire Lee-Menting Technique (Aimoo Post Revisited)
I'm not trying to repeat myself here...however, by request...
The title and following text are a copy of a sticky post I made on the old Aimoo Cast Bullet forum on 03/20/2004.
...well at least for my 6 Lee moulds.
I lik Lee molds for their price and light weight...and in general their bullet designs (most are well tested copies from over the years). I have disliked them because they've never dropped bullets to my satisfaction and frequently suffered from poor fill-out. One was so bad I resorted to prying the bullet out of one of the cavities with an awl applyed to the bullet base. I checked for burrs, smoked it, cleaned it, used mold release, all I could think of...to no avail. I was ready to throw it, when I discovered the following solution quite by accident. That was three moulds ago. I now apply the following lee-ment to every new mould. It's worked every time. Bullets drop as well as they do from my RCBS and Lyman molds...first time, every time.
In my opinion, Lee moulds suffer from three main flaws...bad cavity finishing, poor venting, and bad handle to block fit. Higher end moulds don't...but the extra finishing and quality control adds to cost. So...expect to spend a little time to improve the Lee mould
Those of you who've given up on Lee moulds, I recommend you give the following a try. In addition to usual tools, you'll need a carbide tipped scribe and an aerosol graphite mould release (not for the reasons you suspect), and "Comet" cleanser. Several of the "lee-ments have been described by others and I used their experience in developing it. It's an hour well-spent to avoid "Lee frustration"
1. Look for any obvious burrs in the mould cavity and remove them with a sharp knife. Clean and lube the mold per instructions, smoke the mould if you wish, and begin casting. If your bullets fill out drop as advertised, consider yourself lucky, you need read no further. If not, cast 4 well filled-out bullets(hopefully the handle bolt pounding trick will free them) and save them (you'll likely need only two, the others are spares). While the mould is hot, carefully loosen the spue plate screw until it falls free under it's own weight. I've found that if I do this cold, it's too loose while hot. It you back it off too much, you need to tap a screw to hold the spue plate screw in place. Carefully (you don't want to drill the mould), place two bullets back in the mould and using about a 3/32 bit, drill a hole about 1/4 inch deep in the bullet base.
2. Clean the mold again. Now spray the entire cavity and mould face with graphite mold release. Let it dry and spray a second coat. The surfaces should be black. Remove the bolt holding the handles together so you can easily get at the mould faces. With a cloth, and "Comet" clean the block faces. The fine venting lines will stand out...filled with graphite. Take the carbide scribe and run it down each vent line, deepening and widening them (not too much but enough to be noticeable) between the mould cavity and the edge of the block. Put the handles back together. Fill-out problem solved.
3. Screw a 1 to 2 inch long screw into the hole in one of the bullets, wet the bullet, and sprinkle some Comet on it. Place it into the bullet cavity and with a drill at slow speed and the mould closed on the bullet, rotate the bullet in the cavity. Continue until the mould fully closes on it. (Comet as a polisher is another board members idea...don't remember who...but thanks...it works). Repeat a second time. Use another bullet for the other cavity, if you have one, and repeat. Now rinse the molds and with a toothbrush clean them. Carefull inspect the mould cavities. Burrs and high spots that were previously unnoticed will be seen easily as bright spots surrounted by black...depressions as black surrounted by white mold metal. With a sharp knife, scrape the burrs off and smooth any sharp depressions that represent an imperfection. Go back and repeat the Comet trick twice more for each cavity, clean and inspect the mould for burrs once more. Most of the graphite will be gone, some will remain but will be highly polished, and will help fill the inperfections...it is an aid...not a hindrance so leave it. You now have a polished and repaired cavity...it will drop bullets with the best of them. I don't need to smoke the mould...my old "impossible mould" now works beautifully...it had several imperfections in one cavity that I couldn't spot without the graphite trick. I found it by accident, In desperation had tried the mold release (don't use it for its advertised purpose...bad release problems lie elsewhere), but discovered its real value while trying the Comet mould polishing trick. Bullet release solved.
4. I use a 6 gallon plastic bucket when casting. I fill it with water and place a cloth with a four inch slip in it for water-quench bullets. For air cooled, I fill it with rags as a cushion. However, I lay a flat piece of wood (1X4) across the back half of the bucket. Most Lee moulds have bad handle alignment...especially the double cavities. They frequently don't meet squarely when opening or closing. This wears the block face as the two rub together ...eventually wearing off the vent lines. If you lay the rear of the mould blocks on the flat board when opening them, they will open squarely...same for closing. This saves the mould and aids in bullet release. Handle alignment solved.
Sorry about the long post...however, thought it might be of use to those of you who've given up on a Lee mold. If you're not satisfied with the performance of your Lee, I suggest you give it a try. I've had 100% success to date...it works!
Thanks for the great post MTWeatherman!
I use the same process with lapping compounds with some of my iron molds to resolve release problems and mild rust issues. This process can do wonders to restore an otherwise useless mould to better than new condition with round cavities.
You can imbed grit on the body bands of your lap boolits to get an extra .0005" in the body or imbed grit on the nose of your lap boolits to increase nose size. You have absolute control over this process by selecting the grit size you imbed your lapping boolits with.
I use 600 for light surface rust removal and polishing, 320 grit works well for body and nose size modifications followed by a polish with 600 or 800 grit.
You'll be surprised how long it’ll take to enlarge a boolit cavity .0005" with 320 grit.
Brownell's has polishing compounds as fine as 1200 grit. I'm going to guess that Comet Cleanser is twice that at 2400 grit.
To prevent surface rust store your iron moulds in a Rubbermaid food storage containers with airtight lids or an old GI ammo box and throw some of those silica gel packs (aka descant) that came in the packages of your electronics items.
Boomer :Fire:
