Reloadingtips.com

 
 

 

Address
web@loansoftware.com

 

 
 
 



Test the assertion:

Bullets cast of alloys with antimony expand as they age.



Revised 12/17/2011

Experiment 110920-A

Background:

I have already documented this phenomenon but I have been informed I missed the window where the effect occurs.

Prior data covers the time from opening the mold up to eight days and then skips to many months. After closing this experiment, I am told that the fattening happens after a "week or two".

Experiment setup:

I want to measure length as well as diameter. Previous tests have demonstrated that measuring length is a real problem due to the mold seam at the tip of the bullet and the sprue cut at the bottom. It is difficult bordering on impossible to measure the length of a cast bullet with a flat point and get any type of consistent reading.  For this experiment, I wiped the tip and the base of each bullet on a piece of used 220 grit emery paper placed on a flat surface until I could detect no bumps or ridges.

It is critical that each measurement be of the same bullet as the last measurement so each bullet was identified as to which mold filling it came from and whether it was cavity 1,2,3, or 4.

Diameter measurements are taken perpendicular to the seam. Each bullet is marked on the base with a fine cut by an exacto knife showing the diameter to measure and each measurement is taken across that marked diameter.

The above photo illustrates how I kept up with the individual bullets so a separate record could be maintained of the measurements of each individual bullet.

On the right side of the block, you will notice one bullet with the nose colored red. This is my control bullet. It is the  same bullet, cast from the same mold with the same alloy but it was cast about three months before the experiment began.

The rows of four bullets are cavity 1,2,3, and 4 from a four cavity mold. Each row is a separate pouring.

You will also notice a screw driver bit. This is another control. I find it very difficult to measure the diameter of these bullets accurately, especially the as-cast bullets because they are not round. I draw a line on the base of each bullet to give me the location of the measurement. The sized bullets are significantly easier to measure because they are considerably more round than the as-cast.

The Screw driver bit was chosen for two reasons: It is not an antimonial lead alloy and should not be subject to any growth or contraction effects of the test bullets. It is hexagonal in shape and has flat sides making consistent readings much easier than a (semi) round test object. The use of the screw driver bit is to calibrate the micrometer each day. If the diameter of the screwdriver bit changes, the fault is with the experimenter, not the experiment.

Results first 87 days.

Left four columns average measurements of 16 bullets as-cast.

Right four columns are average measurements of 8 bullets sized with a Lee .357 push-through sizing die.

The bullets are Ballisti-cast # 651.

The alloy is clip on wheel weights.  All bullets were poured at the same time, from the same pot and represent 24 consecutive bullets from the same pot.

Date Day
Diameter Variation Length Variation Growth Growth
Diameter Variation Length Variation Growth Growth




Max - Min
Max - Min Average Average

Max - Min
Max - Min Average Average







Dia Length




Dia Length
9/21/2011 0
0.36155 0.00150 0.69981 0.00040 0.00000 0.00000
0.35744 0.00040 0.70313 0.00210 0.00000 0.00000
9/22/2011 1
0.36153 0.00130 0.69970 0.00040 -0.00003 -0.00012
0.35744 0.00040 0.70301 0.00190 -0.00011 -0.00011
9/23/2011 2
0.36152 0.00130 0.69973 0.00040 -0.00001 0.00003
0.35744 0.00040 0.70301 0.00190 0.00000 0.00000
9/24/2011 3
0.36152 0.00130 0.69974 0.00040 0.00000 0.00001
0.35744 0.00040 0.70296 0.00190 -0.00005 -0.00005
9/25/2011 4
0.36153 0.00130 0.69974 0.00040 0.00001 0.00000
0.35744 0.00040 0.70296 0.00190 0.00000 0.00000
9/26/2011 5
0.36153 0.00120 0.69974 0.00040 0.00000 0.00001
0.35746 0.00040 0.70296 0.00190 0.00000 0.00000
9/27/2011 6
0.36151 0.00120 0.69974 0.00040 -0.00002 0.00000
0.35746 0.00040 0.70296 0.00190 0.00000 0.00000
9/28/2011 7
0.36151 0.00120 0.69974 0.00040 0.00000 -0.00001
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
9/29/2011 8
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
9/30/2011 9
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/1/2011 10
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/2/2011 11
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/3/2011 12
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/4/2011 13
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/5/2011 14
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/6/2011 15
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/7/2011 16
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/8/2011 17
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/9/2011 18
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/10/2011 19
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/11/2011 20
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/12/2011 21
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/13/2011 22
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/14/2011 23
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/15/2011 24
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/16/2011 25
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/17/2011 26
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/18/2011 27
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/19/2011 28
0.36151 0.00120 0.69974 0.00040 0.00000 0.00000
0.35750 0.00040 0.70296 0.00190 0.00000 0.00000
10/25/2011 34
0.36151 0.00120 0.69963 0.00040 0.00000 -0.00011
0.35755 0.00040 0.70296 0.00190 0.00000 0.00000
10/28/2011 37
0.36151 0.00120 0.69948 0.00040 0.00000 -0.00014
0.35756 0.00040 0.70296 0.00200 0.00000 0.00000
11/3/2011 43
0.36151 0.00120 0.69949 0.00050 0.00000 0.00001
0.35755 0.00050 0.70294 0.00190 -0.00003 -0.00003
11/10/2011 50
0.36151 0.00110 0.69949 0.00040 0.00001 0.00000
0.35756 0.00040 0.70294 0.00190 0.00000 0.00000
11/17/2011 57
0.36151 0.00110 0.69949 0.00040 0.00000 0.00001
0.35756 0.00040 0.70294 0.00190 0.00000 0.00000
12/17/2011 87
0.36153 0.00110 0.69949 0.00040 0.00002 0.00000
0.35758 0.00040 0.70294 0.00190 0.00000 0.00000
01/17/2012 118
0.36153 0.00110 0.69949 0.00040 0.00000 0.00000
0.35758 0.00040 0.70294 0.00190 0.00000 0.00000
02/17/2012 149
0.36153 0.00110 0.69949 0.00040 0.00000 0.00000
0.35758 0.00040 0.70294 0.00190 0.00000 0.00000


 

 

 

 

 

 

 

 

See Raw Data Here.

 

Questions or comments: 

web@reloadingtips.com

 

Measurements began 09/21/11

 
   
 

 
 

home | products | about use-mail


 
 

Right 1
Right 2


Right 3