So Mark - that depends on how much you smoke and how long you plan on living:
http://www.thepipetool.com/blog/2016...accopocalypse/
This nice man thinks 70lbs - calculated at 1 bowl per day x 30 years.
The problem being the imperfect science of it all, and the more you smoke, the quicker you will consume your stash, but the more you hasten your demise....
Considering my job, BMI and smoking habit, 30 years is very optimistic.
