This neat post card is on ebay (search - Krag). It was mailed and is Post-Marked: Mobile, Ala., August 22, 1907.

Labeled "Co. F. 600 Yard Range", the individuals, (likely National Guard), seem to be 'Posed'.

It is unlikely they are in the actual act of Shooting. The rifle bolts are not cocked. The men are in three different shooting positions.

The 'elbow pads', on the man displaying "Offhand", are an interesting feature. (Go for it Paul. BTW - They're for Prone)!

It appears the rear sights are model 1901 in 'down position'. The front sights appear 'blackened with soot', so maybe there was going to be some actual shooting.

The slings are Krag slings and appear adjusted for 'Carry'. It is unlikely these pre-1907 slings were used as a 'Shooting Aid'.

The pads remind me of something I did in AF basic training.  We got to dry fire on day one, from prone, and man did crawling around that pavement ever hurt my elbows.  That night I found some socks in the trash and cut the ends out so I could wear them under my fatigues the next day for live fire!