Up until at least the mid 1960's there were Remington 40X rifles issued t o USAR units. These rifles were not used for training, unless you consider marksmanship competition as training. What caused most of the .22 trainers in USAR and NG units to go out of use was the indoor ranges not meeting OSHA air quality standards. It was too expensive to improve the air quality in most of them to bring them into compliance.
This probably coincided with the reduced emphasis on marksmanship training in the military.
Information
Warning: This is a relatively older thread
This discussion is older than 360 days. Some information contained in it may no longer be current.