Brand new to this board, so excuse me if I step on a couple of toes.
Simple engineering supports the fact that the hammer spring stores the same amount of energy, redardless of the rate of trigger pull, excepting only rearward inertia of the hammer, which has minimal mass.
Ohio, unlike Texas, gets COLD in the winter; cold enough to stiffen grease, and other lubricants, as might be found in the firing pin bore, or on the firing pin spring.
Another possibility, and a more likely one, is headspace/ case dimension.
I'm very interested in this pistol, so accurate resolution of this issue is also of great interest. Is there any chance the Brass still exists, identifiably, for measure???