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I test drove my NEI 311-154 4 cavity today and turned out some really good looking boolits, fast! I found a .7 grain difference in weight and .002" difference in diameter and was wondering if this was normal?
I found it very difficult, however, to cut the sprues. It's almost as if the handle on the sprue plate is too short and I had to resort to banging it with a mallet, also my thumb, ouch :( ! I reversed the mold on the handles (Lyman) but, had to drill a couple more holds so they would fit. Now the sprue plate is facing foward so maybe it will help. How do ya'll overcome this problem?-JDL
04-03-2005, 11:49 PM
.............I'm not familiar with multiple cavity NEI blocks so I can't recommend or even suggest how to go about a specific fix. I think the Lee 6 cavity blocks have a good idea in thatthe handle has a cam which bears against the side of the blocks. The initial movement rotates the cam and provides a heckuva bunch of leverage to begin shearing the sprues.
I know that even in 2 cavitiy blocks when casting with a hard alloy you almost have to clamp the blocks in the vise and beat the SP over.
Suggestions: First, be sure the sprue holes are sharp. If there is a visible flat, it should be sharper. Make an extension for the existing SP handle to increase your leverage. You can get steel in 3' lengths at the hardware store. I'd go 3/16" thick. Cut off a suitable length, file the ends all nice and rounded, etc. Drill and tap 2 holes and join'em together.
All my molds with more then 2 holes (other then a Lyman 35863) are the Lee 6 cavity, and the cam action does a good job. In the Lyman, since it's a pistol bullet mould for a 158gr WC, the alloy has never been really hard. I did cast some at 14 bhn which is a bit over WW hardness. I use the same routine for it. I have the SP facing away from me (pivit end closest to me). Sitting in my spruebox I have a piece of wood and I rest the end of the blocks on this, and then strike the SP down.
This starts cutting the sprues. Then I lift the mould and tap the SP on around. Works well. The piece of wood is to elevate the blocks further away from the bottom of the box so the SP can swing some.
"................ I test drove my NEI 311-154 4 cavity today and turned out some really good looking boolits, fast! I found a .7 grain difference in weight and .002" difference in diameter and was wondering if this was normal?"
The weight variation isn't excessive. By being .002" difference in diameter, do you mean out of round or larger overall in diameter? OOR means running a caliper or mike around the boolit and on one side of the parting line you have .309" and on the other side .311", or do you mean the boolits are running .313" (or somesuch) all the way around?
The size was measured opposite the parting line and there is one cavity that measured .313" instead of the .311" of the others but, that was just one casting, not much data to go on. Anyway, that one will work fine in my 7.62X39 if not in a regular .308".
I had thought of adding an extra length of metal to the SP but, didn't know quite how to anchor short of welding or brazing. Thanks for the tip.-JDL
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