You can't achieve a full loadout atm. You'll always be one rocket & one mag shy. This is because the ammunition that's chambered up in the weapons, comes from player inventory instead of going straight into the chamber from the .ext.
Basically, it looks like the ammunition is placed into your bags (vest, uniform & backpack) first & then loaded into the weapon immediately after (with no animation). For example, rendering an assault back pack with only 1 PCML (Missile) instead of 2 Missiles. And 1 chambered up in the launcher. Leaving a half full back pack.