Claims By RG Being Repeated
Claim: The variations of copper in WCC/MC lead come from
microsegregation
Response: False. While there is certainly microsegregation of copper
in this lead, the variations of copper in actual WCC/MC samples show that
something else is controlling its abundance.
Claim: Guinn misunderstood the variations of copper because he didn't
understand microsegregation.
Response: False. See previous response.
Claim: You can't understand the groupings of fragments without being
authorities on elemental metallurgy.
Response: False. Metallurgy is not required for this task, and in fact
has generated the wrong answer in this article.
Claim: RG used cross sections from two WCC/MC bullets to show that
there is no difference between them and the hundreds of other types of bullets
that they have analyzed.
Response: False. They have not done this type of
cross-sectioning on other bullets. Their claim, such as it was, was based on
other, very general considerations and not supported in their paper.
Claim: RG's conclusion that there is nothing special about MC lead is
"devastating" to Rahn/Sturdivan.
Response: RG may conclude that, but they have not shown it with actual
elemental data. In fact, the available data show the opposite, that MC lead is
different from most others, just as Guinn claimed.
Claim: The samples analyzed by Guinn were too small to adequately
characterize MC lead.
Response: False. The consistent log-normal distribution of antimony for
all four batches shows the opposite.
Claim: The photomicrographs of grain structure in the MC lead show
that the elemental data for the fragments are subject to serious doubt.
Response: False. The entire suite of data for the fragments shows that
grain structure does not detectably affect the elemental concentrations in the
fragments.
Claim: Sturdivan does not know that Guinn's 14 test bullets are a
random sample of the four million rounds.
Response: False. (a) Random samples are those that are taken without
sampling bias from the available population. (b) The overlapping log-normal distributions for antimony
from the four lots show that the samples were effectively random.
Claim: Rahn speculates that the MC bullets were mixed in a
ridiculously thorough fashion before they were shipped.
Response: False. No assumptions here. The actual data show that the 14
samples properly represented the lots.
Claim: Rahn/Sturdivan ignore national standards for selecting samples.
Response: False. This is not an assembly-line process where you can pick
and choose. You have to use the available samples, and they are shown to be
properly representative.
Claim: Rahn/Sturdivan are inferring a population from a nonrandom
sample.
Response: False. See the above responses.
Claim: The bullet data are inconclusive.
Response: False. They offer solid answers, to the 3% level at worst and
to one in a million at best.
Claim: The low levels of antimony and silver in MC lead are common in
other ammunitions.
Response: True, and Guinn acknowledged this.
Claim: Therefore the analysis can't eliminate a host of other bullets
as having produced the fragments.
Response: False. The statistical treatment does that, to 3% at worst and
one in a million at best.