Converting a Lee Pot to Pressure Pouring

[rsterne]

I would imagine I am not alone in having problems casting small caliber hollowpoint bullets, and in particular skirted pellets.... particularly in regards to incomplete fillout…. I use a 10 lb. Lee Bottom Pour Pot (the drip-a-matic), and even running it way up at 900*F with 40:1 alloy (2.5% Tin) my reject rate is dismal....

I have been looking at the spectacular results that Wayne has been getting with a hooded dipper and pressure pouring, just a few rejects out of 500 skirted pellets.... and wondered if I could adapt my Lee for pressure pouring.... I had tried it stock, and the small rounded spout went so deep into the taper in the sprue plate, and sealed against it, so you couldn't tell when the cavity was full.... My solution was simple.... I got out a grinder, gathered up my courage, and ground the bottom of the spout off flat, just below where the taper on the spout transitioned into the rounded end.... I then filed a notch, facing forward, using the corner of a square file, to create a path for the lead to escape from the tapered hole in the sprue plate.... Here is a photo of the modified Lee spout....



When you cast, you lift the mould up so that the end of the (now shorter and flat) spout hits the inside of the tapered hole in the sprue plate, and lift the handle to pour the cavity.... You MUST start at the front cavity and work towards the rear, or the overflow, which happens quite quickly, runs into any hole forward of where you are pouring, and stops you from pouring that cavity on that pour.... Hold the mould at about a 45 deg. angle to the base of the pot, so that the overflow (which comes towards you) is easily visible.... Stop pouring before the lead runs over the edge of the sprue plate, of course.... You will see this....



If you hold the mould up against the spout too long, the lead will solidify and you will have to rock the mould a bit to break off the thin part of the sprue.... The trick is when you see that squirt of lead that indicates the mould is full, lower the handle to stop the lead flow, and then drop the mould down and move it to pour the next cavity, or cut the sprues.... I have only done a few bullets so far, I was so excited by how well this worked that I needed to share it immediately.... Here are some 60 gr. NOE .224 cal bullets, the first few from the mould…. I had 2 wrinkled bullets out of the first 4 (using a preheated mould), so even without getting the mould up to temperature the fillout was perfect....



After I do some more of these, I have some 24 gr. HPs to cast in .172 cal.... THAT should be a critical test.... I'll let you know how it goes....

Bob

[rsterne]

Very small bullets, and in particular if they are HP, or have a skirt like a pellet.... are very hard to get to fill out.... I recently got a PID controller for my Lee pot, and even running over 900*F, with hot moulds, my reject rate on pellets was 30-50%.... With this very simple mod. to the spout, and pressure pouring, I can't believe the difference.... 8)

I cast some 25 gr. HPs today in .172 cal, and here is a photo of just a handful of random bullets I scooped out of the tray....



You have to see these little gems to appreciate them.... they are less than 1/2" long, and the HP is not much over 1/16" in diameter.... I also cast some of the NOE .217 cal Magnum Hunter pellets today.... This is a mixed batch of 24 & 26 gr. pellets…. The mould comes with 4 sets of base pins to produce 4 different weights of pellets.... These are the lighter two....



Here is a closeup of a random handful of them, you can see the two different skirt depths....



The 61 gr. .224 cal and the pellets were cast at 800*F, the tiny .172 cal HPs at 850*F.... For anyone who is having difficulty casting small, intricate shapes.... try modding the spout and pressure pouring.... I will NEVER go back....

Bob

[rsterne]

Here is the mod. I made to my Lee pot....



Bob

[clodhopper]

Very nice castings Bob.

[Conditor22]

I love it when people think outside the box.

[dragon813gt]

Did you weigh them, say 100, to see if it increased consistency? Doesn’t take long to plot a bell curve.

[rsterne]

No I haven't done that, and I wouldn't have a reference from previous pellets in any case, because all my casting so far is with new moulds…. I would think that more complete and consistent fillout would mean more consistent weights, no?....

Bob

[rsterne]

I weighed some .30 cal. NOE Hunter pellets I cast today, after throwing any with improperly filled out skirts back in the pot.... Here are the results....



The variation, from lightest to heaviest for both the light pellets and the heavy ones, was 0.6 gr (1.2-1.3%), with most of the pellets being within 0.4 gr (0.8-0.9%).... I think that's pretty good, better than a typical tin of swaged pellets.... even the good ones run 2% or more variation within a tin....

Bob