The best reason I can give is that bolt action rifles are faster and easier to reload than lever action rifles.
Lever action rifles have a tubular magazine, and by the time of WWI, most were loaded from a side gate, one round at a time…
Whereas a Bolt action rifle has a box magazine, which could load the magazine to full from a “stripper clip”. All the soldier had to do was insert the clip into the rifle, and press down on the ammunition to “strip” the rounds into the magazine.
The added advantage is that the ammunition was distributed to the troops, already loaded into the stripper clips.
Edit: An additional consideration is that lever action rifles are very difficult to fire from the prone position, not so much of an issue with bolt action rifles.
Writer: David H (call me WarpedFactor)
