I think a lot of the shortage was caused by panic initially. Add to that the volume of 556 ammo that was purchased in the past couple of years and it’s not hard to see why there was a shortage. Business is supply and demand so when you have an imbalance of demand for one particular round manufacturers start focusing on what makes the most money. They took most of their resources and put them towards making 556. That brought the other calibers to a grinding hault. Now that the frenzy has ebed they are making other calibers again. The government may not have caused the shortage directly but we are seeing an ever increasing militarization of all departments. Like the USDA sub gun request. Those guns will need ammo too so as government expands its army so will ammo purchases.