Waterman,
4 inch guns or 4 inch gun carts? Either one would be impressive and smelly spaying from the waste water pond.

I have done 2 tests with the gun cart using the P85 guns with 11/16 nozzles. Each time I tested it rained 4 times the previous rain starting before I could even complete the test. It rained .2 inches a week before the first test and .8 inches during that first test. The second test a couple of days later a 3.4 inch rain started before I finished.  I was thinking about testing it today as I will have a few minutes free but I am not sure we are ready for 13.6 inches of rain.
Thinking about hiring my self out as a rainmaker "have water gun will travel".
Specifications as it sits today. Twin 69 caliber barrels and built in chamber pressure gauge. 4'' valve head with 2 inch reducer beside the cart.
Gotta be careful with these big guns, they could put an eye out at close range.

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