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@moth
If we're doing physics, lets do it properly. Force = pressure x area. Double the diameter and you get four time the cross sectional area, so *four *times the force to reach the same pressure. Or more generally, the force needed is proportional to the square of the internal diameter.
I once built low-force 'track pump' from a specialized airtool road frame pump. It was intended for use by children launching water rockets, who struggled to reach the 50psig or so needed with conventional track pumps. It worked, but pumped tediously small amounts of air, so it was more fun to struggle on with proper track pumps. (I made a wooden T handle and base, and cannibalized the gauge and hose from a proper track pump. I don't still have it. If i was doing it again i'd use a slightly fatter pump and add a non-return valve at the pump end of the hose. (Maybe improvised from an inner-tube valve. Not having one would make it very inefficient at high pressures. That was less of an issue at 50psig.) Some of the longer frame-fit pumps look promising.)