User blog comment:101stranger/Ah, the wonderful world of UNSC infantry weapons/@comment-4791664-20100415105028

On the note of plasma and energy weapons; actually, Plasma Weaponry would be the most probable route for UNSC weaponry post-Human Covenant War, as both recovered technologies from the Covenant as well as knowledge from Sangheili technicians would make development of improved Plasma Weaponry much easier than adapting Forerunner technologies. Also, I don't think that the Spartan LASER is an adaptation of Forerunner weaponry... LASER technology has been in development since the 21st Century.

Then on the topic of gauss weaponry; while it is true that Gauss Weaponry is highly efficient, the main problems with common infantry use lie in cost, power requirements, and size. The M99 SASR, the smallest gauss weapon in the UNSC arsenal, requires a link to an external power source, and must be fired from a prone position, due to its large and bulky size.