the field artillery journal - Fort Sill - U.S. Army

SUPPLEMENTAL NOTES ON LOST MOTION
the laying. The author of the criticism on page 534 holds up
with levity a partial quotation, "the idea of checking sweeping
fire by the panoramic sight and quadrant," but he overlooks the
very next sentence, "the gunner, moreover, has a ready check
under his eye on the azimuth scale of the carriage——." The
azimuth scale might be used to advantage by those who strive
for the highest accuracy and most even distribution in
sweeping fire, even though the panoramic sight be of no avail.
Our ammunition allowance is perhaps too low to qualify many
of us in the technique of volley sweeping; still experience
indicates, page 534, that lost motion precludes "any possibility
of regularity between the first and second rounds of volley fire
sweeping." Would it be worth while then for the gunners to
make sure that the pointer of the scale clears about 8 mils in
traverse, one turn of the handwheel, and that the bubble of the
quadrant is approximately central for the second round only of
volley sweeping? It might be pointed out also that the tabulated
statement referred to on page 539 gave displacements of the
piece in the operations of loading only when "as much force as
possible" was exercised by hand. The maximum derangement
in these extreme circumstances was 2 mils in elevation and 7½
mils in deflection. The table of itself has no intrinsic value;
during a few minutes' recess at drill similar experiments in the
usual operations of loading, as performed by service gun
squads, would convince anyone that the greatest derangements
to be expected are far less than those tabulated. Analyzing the
loading operations it will be noted that the only material
derangement occurs in traverse alone and then only in opening
the breech; if the gunner be practiced in bearing his shoulder
against the shoulder guard, this displacement is taken care of
with no loss of time. This practice is important because in
effect it serves almost the same purpose as checking back on
the azimuth scale. It may be said on behalf of the opponents of
the "check back" that it is considered an unnecessary
refinement in sweeping fire; the practice, however, of the gunner
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