I would like some advice on what I may need to consider (variables and procedures) to develop my new ballistic tables for a new AIAW 308 with a 20 inch barrel with a S&B 5x25.
I do not handload. I have started shooting it with Black Hills 175 gr BTHP moly's.
I have a 200 yd zero and use my i phone with the JBM tactical ballistic program.
I am using a 1.8 sight elevation with standard atmospheric parameters with a 10 mph crosswind.
It is dead on at 200 and 300 yds same as the tables. When shooting at 800 yds I am 3 inches low when using the ballistic table data. I have found that adding 3 clicks (1/4 moa) brings me to dead on at 800 yds.
I think the scope is tracking well as with no crosswind and dialing in 102 clicks it is dead on at 800 yds and is giving me sub moa groups with no horizontal displacement. I am assuming that if it did not track properly that with 102 clicks dialed in it would be off horizontally if a no wind condition.
Why would my elevation adjustments be off? I have tried tables from the database using the black hills ammo and have used the projectile tables and used a variable BC along with 2600 fps. Both tables come up the same but are a little different from what I see shooting at the farther ranges.
Also, should I be considering switching to another bullet such as a AMAX from Hornady or a Scenar?
I have some other ammo from Fiocchi and Lapua that I plan to experiment with ranging from 155 gr Lapua scenars to fiocchi 165 and 168 grain BTHP.
Thanks
I do not handload. I have started shooting it with Black Hills 175 gr BTHP moly's.
I have a 200 yd zero and use my i phone with the JBM tactical ballistic program.
I am using a 1.8 sight elevation with standard atmospheric parameters with a 10 mph crosswind.
It is dead on at 200 and 300 yds same as the tables. When shooting at 800 yds I am 3 inches low when using the ballistic table data. I have found that adding 3 clicks (1/4 moa) brings me to dead on at 800 yds.
I think the scope is tracking well as with no crosswind and dialing in 102 clicks it is dead on at 800 yds and is giving me sub moa groups with no horizontal displacement. I am assuming that if it did not track properly that with 102 clicks dialed in it would be off horizontally if a no wind condition.
Why would my elevation adjustments be off? I have tried tables from the database using the black hills ammo and have used the projectile tables and used a variable BC along with 2600 fps. Both tables come up the same but are a little different from what I see shooting at the farther ranges.
Also, should I be considering switching to another bullet such as a AMAX from Hornady or a Scenar?
I have some other ammo from Fiocchi and Lapua that I plan to experiment with ranging from 155 gr Lapua scenars to fiocchi 165 and 168 grain BTHP.
Thanks