I'm your guy. First they are heavy to haul around all day. How much weight to you want to haul? You can buy them already made. Your basic garden sprayer. A recycled fire extinguisher is best. Seen Super Soakers and a 5 gal bucket used to defend HQ from up in the tower. They seemed to be having a blast.
You want to be able to reload and recharge it quickly.
Flame throwers are best used on GROUPS of player holed up in an open topped bunker or a tank if the rule allow. You wouldn't go after a single guy unless it was for mission points, general kill, etc.
Using water or other thin liquid maxes out at about 20-25 feet. The same distance you get out of a garden hose sprayer. Barely the distance between bunkers at most fields. The MORE pressure you put behind it, the more it atomizes. Max for water is about 100 psi range.
So you need a thicker simulated 'napalm' to get a decent range. How does 20 yards sound to you? 50% water and 50% regular, heavy drywall mud. Stired and not shaken. (pun) That makes 10 gallons for $15 or so. The pigment is LIME and it is water soluble but slowly so when they whine tell them they should soak overnight before washing. Might want to take a copy of the MDS sheet to the field with you to show them it is not a safety hazard, biodegradeable, non toxic, etc.
You can put 200 psi on that mix in a fire extinguisher body and get 20 yards out of a 1/8" nozzle. You can get them for free or cheap at your local fire extinguisher supplier. The non rechargable, disposible, 2-3 pound ABC Kiddie fire extinguisher., They go flat or have been used and they just sell them for scrap aluminum.
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