New Lyman 4 cavity #452630 results

[Jumping Frog]

After getting everyone's help in the thread "Lyman-enting version of Lee-menting? (http://castboolits.gunloads.com/showthread.php?t=57576)", I prepped my new Lyman 4 cavity mould: 45 Auto - #452630. These I cast some boolits using straight wheelweights.

In the above thread, people mentioned concerns about undersized or eccentric boolits with new Lyman moulds. I measured the diameter for 25 sample boolits in two dimensions using a micrometer. Once along the mould part line and then at right angles to the mould part line. Measuring at right angle to the part line was pretty consistently small than measuring along the part line.

I am asking for feedback on two aspects of the numbers.

First, the average eccentricity is 0.0008" (8 ten-thousandths), with a maximum eccentricity of 0.0022" (22 ten-thousandths). Is this degree of roundness acceptable quality, or should I be complaining to Lyman.

Second, 14 or 25 (56%) of the boolits measured less than 0.4510" when measured at right angle to the part line. Slightly small. I figure if I complain about this they will simply point out that I should use their faced "#2" instead of straight wheel weights.

I figure I'll load and shoot them next and see how they perform while undersized. However, I suspect I will find myself needing to hone these cavities out slightly after testing.

What do you think?
================================================== ===========
X is across part line
Y along part line


Average: X=0.4510, Y=0.4519, Difference=0.0008
Maximum: X=0.4528, Y=0.4536, Difference=0.0022
Minimum: X=0.4500, Y=0.4503, Difference=-0.0006
Std Dev: X=0.00066, Y=0.00064, Difference=0.00071
Samples
(sorted by X)

X=0.4500, Y=0.4522, Difference=0.0022
X=0.4502, Y=0.4515, Difference=0.0013
X=0.4504, Y=0.4515, Difference=0.0011
X=0.4504, Y=0.4518, Difference=0.0014
X=0.4505, Y=0.4503, Difference=-0.0002
X=0.4505, Y=0.4512, Difference=0.0007
X=0.4506, Y=0.4514, Difference=0.0008
X=0.4506, Y=0.4514, Difference=0.0008
X=0.4506, Y=0.4523, Difference=0.0017
X=0.4507, Y=0.4515, Difference=0.0008
X=0.4507, Y=0.4518, Difference=0.0011
X=0.4508, Y=0.4515, Difference=0.0007
X=0.4508, Y=0.4523, Difference=0.0015
X=0.4508, Y=0.4528, Difference=0.0020
X=0.4510, Y=0.4511, Difference=0.0001
X=0.4512, Y=0.4516, Difference=0.0004
X=0.4512, Y=0.4524, Difference=0.0012
X=0.4513, Y=0.4518, Difference=0.0005
X=0.4514, Y=0.4521, Difference=0.0007
X=0.4515, Y=0.4522, Difference=0.0007
X=0.4516, Y=0.4520, Difference=0.0004
X=0.4518, Y=0.4536, Difference=0.0018
X=0.4519, Y=0.4516, Difference=-0.0003
X=0.4521, Y=0.4523, Difference=0.0002
(sorted by Y)

X=0.4505, Y=0.4503, Difference=-0.0002
X=0.4510, Y=0.4511, Difference=0.0001
X=0.4505, Y=0.4512, Difference=0.0007
X=0.4506, Y=0.4514, Difference=0.0008
X=0.4506, Y=0.4514, Difference=0.0008
X=0.4508, Y=0.4515, Difference=0.0007
X=0.4507, Y=0.4515, Difference=0.0008
X=0.4504, Y=0.4515, Difference=0.0011
X=0.4502, Y=0.4515, Difference=0.0013
X=0.4519, Y=0.4516, Difference=-0.0003
X=0.4512, Y=0.4516, Difference=0.0004
X=0.4513, Y=0.4518, Difference=0.0005
X=0.4507, Y=0.4518, Difference=0.0011
X=0.4504, Y=0.4518, Difference=0.0014
X=0.4516, Y=0.4520, Difference=0.0004
X=0.4514, Y=0.4521, Difference=0.0007
X=0.4515, Y=0.4522, Difference=0.0007
X=0.4500, Y=0.4522, Difference=0.0022
X=0.4521, Y=0.4523, Difference=0.0002
X=0.4508, Y=0.4523, Difference=0.0015
X=0.4506, Y=0.4523, Difference=0.0017
X=0.4512, Y=0.4524, Difference=0.0012
X=0.4508, Y=0.4528, Difference=0.0020
X=0.4518, Y=0.4536, Difference=0.0018

[Blammer]

I'd size em to .452 and shoot them.

I've never looked THAT closely at my cast boolits before.

I'd think you should be able to hit a pie plate at 10 yds with them. :)

[anachronism]

After considering all aspects of the situation, it is my professional recommendation that you follow Blammers advice. You will see some variation in diameter as the mould heats up. Tin may help, as may a wee bit more antimony, like a 50/50 lino/WW blend.

[2Tite]

I think Blammer's advice is sound. It's VERY hard to have a "round" bullet come out of a cherry cut mold. I think much too much is made of concentricity of "as cast" bullets. We (collectively) should more aptly consider concentricity of our sizing dies. You don't often hear that considered but, in my mind it's probably more applicable.

[243winxb]

You seem to have a wide spread in diameters. Are you fluxing the pot? Are the smaller diameter bullets frosted? If the groove diameter of your barrel is .451" or smaller you may be OK. A bigger groove diameter barrel, will not give you match grade accuracy. If your happy hitting a 9" pie plate at 25 yds, load them.

[captaint]

Jumper - Are you using any mold release stuff?? That will make your boolits at least a little smaller. If so, try casting without - it's no handicap. Mike

[runfiverun]

if you measured them right after you made them remeasure them after aboput a week.
if they are say 4526 one way and 4513 the other they will be close enough to 452 after you size them your gun really won't care.
i have a few molds that when i size them it just scrapes by the parting line and they do dandy when shot.
if you are gonna shoot bullseye at 75 yds you have other things to worry about.