If you don't think too good, don't think too much.
Figure 1: Illustration of Typical Home Plumbing Vent System (Source).
My coworkers and I often discuss our home remodeling/repair adventures. This morning, a coworker described how a neighbor in his home town used a rifle to solve a common plumbing problem. I do not condone this approach and I am appalled at every possible level that someone would even try it. I think it is general knowledge that if there is an issue with the Plumbing of your home then you will 100% need to call a professional plumber in to get it sorted so that everything is up to code and there is very little room for error. That is certainly my hope anyway, so if you are reading this and believe that picking up that rifle in your home and using it for a problem like this (or any other issue) then you definitely need to take a few steps back and realize that there are a myriad of professionals out there that can help you with any issue that will crop up in your house... put down the rifle.
His neighbor had to run a vent pipe (see Figure 1, vent pipe in red) from an interior room to the roof. Running a vent pipe requires putting holes in walls and floors so that you can run the pipe to the roof. Generally, I solve this problem by taking careful measurements, drilling unobtrusive holes to verify my location, etc.
My coworker's old neighbor came up with a unique solution. Why not just shoot a rifle vertically through your house to mark the path for your vent pipe?
My mouth dropped when I heard this. Once again - call a professional, I beg of you.
maybe a laser pointer could combine the advantages of both proposed methods ...
I use a 5-point laser level myself (i.e. top, down, front, right, left). Some folks don't want to spend a money on laser levels. However, a rifle is certainly not the correct measurement tool.
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