Change 1, 30 June 1995
e) The OB may be placed on a flatter slope and overlapped to
function as FL canopies if multiple FL's are to be used. See Figure 2.2-11.
This arrangement is cost effective for baffled combat lanes.
188.8.131.52 Ricochet Containment. On Type "FB" ranges, construct non-ballistic
panelling in accordance with Figure 2.2.12. Alternative materials and methods
to prevent RC from leaving the range may be presented to NAVFACENGCOM Code 15C
for prior approval.
184.108.40.206 Impact Structure. The structure varies depending on the type of
range. Acceptable structures by range type are listed below. Alternative
methods may be presented to NAVFACENGCOM Code 15C for prior approval.
a) Type "O" Ranges. The top elevation of the impact structure
should be plus 8.0 meters FLFS for ranges 92 meters or greater in length and
plus 5.0 meters above FLFS for ranges 50 meters or less in length. The impact
structure should extend 45 meters beyond the target line ends for 92 meter
ranges and 15 meters for 50 meter ranges , or until joining with the side
containment, if provided. Locate the beginning of the structure as close to
the last target line as possible.
(1) Earth Berm. The suggested elevation may be met by
designing a combination of earth berm and vertical baffle (Figure 2.2-13).
The earth berm portion should have a top elevation of plus 5.0 meters above
FLFS. The vertical baffle shall be constructed of ballistic material (par.
220.127.116.11) and designed to withstand local seismic and wind loads. This
combination arrangement would reduce the footprint and the amount of material
in the earth berm. The slope of the impact face should be no lower than 1.0v
to 1.5h. The top should be 3 meters wide. The impact slope should be
constructed with a 1 meter layer of easily filtered soil (to reclaim the lead
rounds) with no rocks, sticks, etc. The impact face of the berm will be
periodically mined for spent lead , so consider maintenance when designing.
The rear slope should be appropriate to the native soil and maintenance
requirements. Vegetate appropriately to prevent erosion.
(2) Reprocessed Rubber Products. New products are coming to
the market. Their use is encouraged if appropriate and cost effective.
Contact NAVFACENGCOM Code 15C for prior approval.
b) Type "PB" and "FB" Ranges. The top elevation will vary
depending upon the OB and impact structure arrangement. The impact structure
for Type "PB" can be: standard berm, bullet trap, or hybrid. For Type "FB"
the impact structure shall be a bullet trap. In all instances, the impact
structure will connect to the side containment.
(1) The standard earth berm shall have slopes and width in
accordance with par. 18.104.22.168.a)(1). Provide geotextiles as necessary to