If you were to build a indoor range...

[GDragich]

View: https://youtu.be/lTwvtGooS5U?si=Vi6xF2XnZz6H1f6y

 

[Lazyfaire]

Above-ground pipe, 3 ft diameter, with a target rail thing? Then one end in a berm built up with clay and hard structure inside?

Edit. Might help reduce reports a bit, especially if you could wrap insulation n stuff on outside, basically a giant silencer tube but not attached to guns

Instead of insulation, cover it with dirt to deaden the sound

 

[Sporting Systems]

Lots of good info in the thread. I'm building a personal 20 yard range in a new building right now, in the basement if you will. Here's the plan I put in place.

Physical construction:
20 yard single pistol bay, 12' wide and 9' ceilings
In a "daylight basement". 16" Concrete walls on all sides, ceiling and slab (its all structural for the upstairs on grade garage.)
Floors and walls will be epoxy sealed.
Entry door is a 40" commercial steel exterior door (opens into adjacent indoor space)

Ventilation
Outside air inlet louver that powers open when range is turned on and air enters behind the shooter, drawn in by the exhaust fan draws clean air to the dirty end of the range. Just over 5000 CFM flow, in an air tunnel that will be about 8.5' wide x 9' tall. No heat or air, just have to suck it up.

Lighting:
More light than you think, good lighting on the targets and at the range bench. Also able to control each light independently to practice with low light and Night Vision. The baffles and tires will adsorb a lot of light, so using double the amount you would normally use.

Brass collection
Brass collection baffles on the right side of the shooter. Saves picking up brass off the floor and consolidates any mess into one easier to clean space.

Sound attenuation:
Sound escaping the bay isn't a huge issue, its a concrete room inside of building and 3 sides are underground and this is a rural location.
Duct work will have a cleanable sound attenuator in the duct along with several changes of direction to depress the Sound Pressure Level
Sound in the space is a huge concern - I don't like shooting inside. "Luckily" we have a huge pile of car tires at our outdoor test range. We're going to line the concrete walls with tires stacked horizontally, and fill with rubber mulch. The tires will be stacked in a zig zag pattern so the wall isn't straight, which helps mitigate sound. The beams on the ceiling will have rubber baffles

Backstop/Bullet
Target Bullet trap - a commercial movable target collection box
Backstop. A 2 layer deep of tires as a back up bullet stop. Front facing tires will be filled with rubber mulch. Back row, will be filled with 1.25-1.5" gravel, finally there is the 16" of concrete, which should never see a bullet fragment.

Clean up:
HEPA filtered shop vac - no brooms, no compressed air.
Delead wipes and hand washing outside the range.

Just some of the things I've researched and been around. Relatively low cost solution, except for a the building shell (but we're doing that anyways). We have a 200 yard outdoor range already, and use that for rifle and pistol. Just really want the ability to practice and train indoors during poor weather.