Define cold bore, in order to impart understandable meaning to this thread.
1) First shot from a fouled cold bore with powder and copper fouling residual in the bore from the prior firing of the gun, or
2) First shot from a clean cold bore, with powder, carbon, and copper fouling removed by thorough cleaning of the bore.
I think most rifles print their first shot to an altered POI under first cold bore shot #2 definition. I've recorded many MVs over the past decade and they are most commonly significantly different from the first cold clean bore shot, compared to the following bullets fired from the fouled bore, whether the fouled bore is cold or warm. The fouling affects the MV.
That change in MV alone could often cause the differing POI on the first shot shot from a cold, cleaned bore.
1) First shot from a fouled cold bore with powder and copper fouling residual in the bore from the prior firing of the gun, or
2) First shot from a clean cold bore, with powder, carbon, and copper fouling removed by thorough cleaning of the bore.
I think most rifles print their first shot to an altered POI under first cold bore shot #2 definition. I've recorded many MVs over the past decade and they are most commonly significantly different from the first cold clean bore shot, compared to the following bullets fired from the fouled bore, whether the fouled bore is cold or warm. The fouling affects the MV.
That change in MV alone could often cause the differing POI on the first shot shot from a cold, cleaned bore.