[Ads-l] According to =?UTF-8?Q?=E2=80=9CBasic_Training_Memories=2C=E2=80=9D_?=a Facebook S.I.G.,

[Wilson Gray]

An “acting jack” is now an Sp4 holding the acting rank of corporal. Back in
my day, an “acting jack” was an Sp5 holding the acting rank of sergeant.

My analysis: today, the only specialist grade is Sp4 (E-4), with the pay
and privileges, but not the rank and duties, of a corporal, the
lowest-ranking NCO. Everyone with the grade of E-5 or higher is a real
sergeant/NCO.

Back when, the highest specialist grade was the same as the highest NCO
grade, E-9, with a specialist having the same pay and privileges, but not
the rank and duties, of the corresponding NCO. But, in fact, a specialist
of a grade higher than E-5 was so rare as to be merely theoretical - I saw
an Sp6, *once*, in my three years of service - making E-5 effectively the
highest specialist grade then, as E-4 is actually the highest specialist
grade, now. So, a specialist acting as an NCO - an “acting jack” - was an
E-5.

-- 
-Wilson
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All say, "How hard it is that we have to die!"---a strange complaint to
come from the mouths of people who have had to live.
-Mark Twain

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