1. Indian Army despise high rate of fire, Many unit modify their service rifle ( 1B1 ) to fire in slow rate, So that we know where our bullets are hitting and we could know its a burst rather than a single shot. more over during night in burst option one tracer round in slow rate enable us to count and fire with accuracy.
2 & 3. Reliability and weight are always the primary factors which decides the fate of a firearm fit for service or not, Present rifles such as 1B1 and AKM and derivatives hardly produce much of a recoil which is negotiable by our standards, Hence compromising with reliability is not a good prospect for an firearm which intend to be in Indian service.
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Unfortunately their is no training with optics with respect to rifleman in Indian Army, Reason we still go around with 1B1 with empty on rail, Their is need for change in rifleman training with respect to new technologies and just not SF.
I personally like ACOG.
And if you are looking for ACOG alternatives, Then this thread might help you, I posted it during 2013 :
http://defenceforumindia.com/forum/threads/acog-alternatives-legal.51466/
Short stroke piston have three major advantage:
1 Higher cyclic rate: because bolt carrier moves with higher velocity in absence of piston attached to it,hence it has higher rate of fire.
2 Less recoil : since the moving mass in short stroke is small(compared to long stroke) ,it has comparatively less recoil.
3 Accuracy: By virtue of less recoil it has good accuracy.
Long stroke has better reliability ,this does not mean that short stroke have bad reliability!Scar is a fine example of it.
Hence, many prefer short stroke piston due to these advantages;it's up to you what do you prioritize.
Sir,please go ahead.
P.S : More than the rifle, good optics will bring in the real difference.Hope army realize their importance and instead of going in for red dot reflex sight ,goes for sight with at-least 4x magnification.