Complex sentence: However, deliveries of the initial shipment of 10,000 rifles were not completed until 1897 owing to delays caused by manufacturing issues and contract changes imposed by the Navy, particularly a change in ammunition specification, which required extensive test firings followed by recalibration of the sights.
Split into simpler sentences: However, deliveries of the initial shipment of 10,000 rifles were not completed until 1897 owing to delays caused by manufacturing issues and contract changes imposed by the Navy. The latter included a significant change in ammunition specification, which required extensive test firings followed by recalibration of the sights.