Need a Lee Buckshot Mold Guru

[5Shot]

I've tried everything, but can't get good fill out and I am getting a reject rate of at least 60%. I'll get a cavity or two that fill out completely and the rest will have the top one or two pieces of shot in the cavity filled out and a little tail where the alloy solidified before filling the lower portion of the cavity. I am using a bottom pour ladle and the alloy is WW +2%. This alloy works great in my pistol molds. The mold is plenty hot and the alloy is at 725. I've poured close and I've poured an inch above the sprue plate. Nothing seems to work. First Lee mold, so not sure if they take time to break in or not.

Any help would be appreciated.

[Ed_Shot]

Sounds like a venting problem. Have you looked at the Leementing threads here?

[5Shot]

I'll do a search.

I kinda thought venting too, but it has so much machining fly cuts on the faces it didn't seem like it would be an issue.

[rsrocket1]

Your sure the mold is really hot? Do you dip the mold in the melt and let the heat really soak in before you start casting? It also sounds like it could be a cold mold. You should also have a really big sprue puddle on the plate to get the sprue plate nice and hot.

[5Shot]

Yeah...dipped in the melt to heat it up, hot sprue plate - takes a bit for it to harden.

[hickfu]

When I get a new mold I take a file and run it across the top of the holes at a 45 degree angle (each side) so I get good venting up top. I dont have the Lee buckshot mold but I was thinking of getting one so I hope you figure it out and pass it on here..

[5Shot]

I did clean up the top already, as it had a bit of a lip on the inside face of the mold halves. Ran a fine file across it to remove it. The problem hear is clearly at the bottom, as I get good fill at the top.

[5Shot]

So...I tried one of the suggestions from the Leementing PDF and put a strip of foil on the bottom edge of the mold. All of a sudden I was getting fill out of the very bottom and the top and a wasp waist in the middle (3 pieces of shot per cavity). So I figured it had to be venting but couldn't believe it was filling the bottom and top but not the center. I tried a longer pour and presto. Even when the foil fell off (plain foil...not tape) I tried the longer pour and my reject rate went to less than 5%.

So...I have to pour for a 4 count on every cavity to get the air out. Luckily my Rowel is a 2 pounder! The next test will be to see how they fly. The top pellet has quite a flat spot where the sprue is cut and I am not sure if that will affect patterns or not. I am guessing yes, but not sure how much. I tumbled them in vibratory tumbler but it didn't round off the sprue cut. I am going to try it in a rotary and see what happens. I would hate to have to cull those 6 pellets every time, since then I am at a minimum of 33% reject right off the bat.

These are going to be used for coyote loads, so I would like to duplicate the patterns I was getting with Hornady buck... This an 18 pellet load with 17 pellets inside 12" and 15 of those inside 8" at a measured 40 yards.

https://farm6.staticflickr.com/5594/14961585465_c55609a93a_c.jpg

[Moonie]

I pressure cast with mine and it works great. I also run this mold very hot, extra tin might help. I use WW metal and water drop then tumble in a rotary tumbler.

[5Shot]

Does the rotary get rid of the large flat on the top pellet?

[Harter66]

WCWW ? That's pretty hard shot ,that alone should close groups.....patterns.
I would try to put the sprue balls against the crimp.

Sometimes my 00B mould runs like a champ other times I'm ready to chuck it. The best I've come up with is to let it warm sprue down on the hot plate. It usually runs about 15-17 per drop for keepers and I get about 1 in 4 that are all kept . I usually only run a 300 or so balls per run . I ran 10 pounds and the returns were much higher . The last 5# was probably about 98%. When I get failure to fill out its usually in 2-3 of the 4 middle cavities and usually the middle ball. I just drop it back on the hot plate and put the sprues in the heating pot give it a couple of minutes and resume casting.

[5Shot]

When it wasn't quite filling them all out I let the sprue cool with the mold on top of the pot. Kept the mold warmer than the cold bench (it's 17 today).

[Harter66]

I find myself resting moulds on the pot to setup also. I try to avoid leaving the kitchen when it gets that cold here.

[5Shot]

I wouldn't be able to leave the kitchen for like the next 4 months! I like winter though...who doesn't like to play in the snow?

[snuffy]

I have all 3 lee buckshot molds. They all require pressure/gravity casting. I use the Lyman ladle with it full-as-possible, then mate it to the sprue plate while rotating it to vertical. A five count, then separate - move to the next cavity. there's sometimes whiskers where the lead tries to enter the vents. A shake in a bowl breaks them off, or you could tumble them. Of course with a very thoroughly pre-heated mold.

I wouldn't be worried about that flat where the sprue is, in theory that could result in a flyer in the pattern. The upset of the acceleration deforms all the pellets, so one with a bit more of a flat side is of little concern. If you were to use a buffer surrounding the pellets, then that deformation is reduced.

My buck loads were loaded for 3 gun competition, so I wasn't too concerned about long range, nice small patterns.

The beauty of the buckshot molds is that you can use harder lead that makes each pellet lighter, reducing payload weight for the same number of projectiles ,(means higher velocity without pressure concerns). Also that harder lead deforms a lot less, making for denser patterns. Water dropping WW metal would be even better. Look up nickel plated buckshot on the BP website. You're making the equivalent to that with water dropped WW.

[5Shot]

I will probably heat treat some to try - I have a nice lab oven that will be getting a PID for heat treating my Big Game slugs.

[Moonie]

Does the rotary get rid of the large flat on the top pellet?

Really depends on the hardness of the shot. With my water dropped WW shot it does help a little but I'm sure it would help more if they were softer. The issue there is that hard shot patterns better as it doesn't deform as much when fired, so it's a trade off. Hard shot with a small flat on 1/3 or softer shot more prone to deformation during firing...