Could different ammunition extend the Pom-Pom's range?

Could changing the ammunition have given the Pom-Pom a longer range?

Yes, but the comparison uses the rounds actually loaded, including the British ammunition with a 5,000-yard maximum range.

A theoretical ammunition change could have extended the Pom-Pom's reach. The quoted figures concern the rounds actually loaded, rather than every possible development. Britain retained ammunition with a 5,000-yard maximum range and also used a corresponding type for Bofors. Bofors used other rounds as well, so the ammunition chosen could narrow or widen the apparent range difference.