Hello to_saptarshi
]Since I don't change my grip during five shot, I see a very tight and consistent group , but they keep shifting right or left in every five shot group. Which I strongly believe happening due to my incorrect zero point or NPA.
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Obviously you shoot on an open range, where the wind does have an effect on the extended arm. That should be taken into account first and foremost. Otherwise, I think you maybe right about your NPA.
In all your video , I have observed that, you directly took the shoot , without even checking for zero point. The reality is you already knew that your NPA is correct and that's why you directly go for shot development process, but how you did that just by looking into the target ?
Your observation was pretty sharp, if you replay the tape where I comment that I will now be concentrating on my SOS and hence no commentary, observe very carefully, you might just see me making micro corrections in the feet position before I pause to visualise and then lift the pistol. Maybe its not all that clear, but Yes!, I didn't bother to check my NPA or Body Zeroing and just took the shot ramming through the slight opposition by my arm muscles , which at that point of time were pulling slightly towards the LEFT. What I should have done; was to stop, adjust my position and then shoot. But I just shrugged it off because the camera was rolling...
Now I wouldn't be so nonchalant if I was shooting a match or even a practice session.
Coming to your point; The quickest way to check your NPA, is to be very tuned in, to what your arm muscles are saying when you lift the pistol, if you feel the pistol is going to the right or left fractionally, then quickly cancel the shot, and adjust your feet, lift your pistol and check whether it is OK.
The above takes practice and you can do it, by consciously practising it. With the passage of time this gets ingrained into your subconscious and the quick adjustment is made without conscious effort.
All right, I promise to address this question in my next video.
Thank you for asking me a really meaning full question and I enjoyed answering you, sincerely hope that my answer satisfies your question completely, if not fire away again till you are satisfied with my reply.
Regards