That is why the rules state 12.5-13.5 psi to compensate for that.
2 lbs. below the lower limit is not a mistake.
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Yep. And they say some QB’s like the lower end of the legal range and some the upper. A ball at 10 lbs is a big difference.
If I pump to the lower and the weather drops it a lb, the statement MIGHT be made two pounds lower IF I use the higher to base my statement
High end (but pumped to 1 lb lower end) minus a hypothetical 1 lb loss = 2 lb underinflated