Hi,
I am new to PCP rifles and new to the forum as well. If this topic was covered earlier or if it is a completely newbie question, I apologize.
Goal is to find the best pellet for a gun. While that sounds simple and the answer maybe to try out as many as you can, I think the narrowing down process can be made more methodical if some existing data is used. Problem is I don't know yet, how to apply them and hence this thread. I got started with a RAW HM1000x .30 caliber. I have tried the JSB Exact .30 cal, 44,75 grain that the rifle is designed for and also the JSB .30 cal, 50 grain. Both of them performed really well at 100 yards with approx 1.5" groups. Wind being the major factor, I am wondering about the effect of ballistic coefficients on accuracy.
To narrow down the search it would make sense to go with something that has the highest BC. Not sure if URLs are allowed in the forum, so google for "Ballistic Coefficient JSB" and look into the first link.
The 0.25 cal JSB Exact King Heavy MK II 33 gr
The 0.3 cal JSB exact Diablo 44.7 gr
and
The 0.3 cal JSB exact Diablo 50.15
immediately stand out with the 0.3 cal 50 grain coming out the highest at 0.053 BC. So if someone has a 30 cal rifle and if shot count or cost is not an issue and if only accuracy is, wouldn't they choose the 0.053 and just tune the gun to shoot it best?
Secondly, if you look at the velocity of the JSB exact 44.7 gr in the link "Hard Air Magazine", why is the 30 yard velocity at 782 fps which is much more higher than the 0.25 cal JSB Exact King Heavy MK II 33 gr, at only 603 fps at 30 yards?
It was all shot out of the same gun and I see an outlier here. Why am I asking this question?
The BC equation suggests, the higher the velocity, the better BC due to the velocity in the numerator. However there are other factors like harmonics. Let's just start with the first two questions and then proceed form there.
Thanks,
Jai
I am new to PCP rifles and new to the forum as well. If this topic was covered earlier or if it is a completely newbie question, I apologize.
Goal is to find the best pellet for a gun. While that sounds simple and the answer maybe to try out as many as you can, I think the narrowing down process can be made more methodical if some existing data is used. Problem is I don't know yet, how to apply them and hence this thread. I got started with a RAW HM1000x .30 caliber. I have tried the JSB Exact .30 cal, 44,75 grain that the rifle is designed for and also the JSB .30 cal, 50 grain. Both of them performed really well at 100 yards with approx 1.5" groups. Wind being the major factor, I am wondering about the effect of ballistic coefficients on accuracy.
To narrow down the search it would make sense to go with something that has the highest BC. Not sure if URLs are allowed in the forum, so google for "Ballistic Coefficient JSB" and look into the first link.
The 0.25 cal JSB Exact King Heavy MK II 33 gr
The 0.3 cal JSB exact Diablo 44.7 gr
and
The 0.3 cal JSB exact Diablo 50.15
immediately stand out with the 0.3 cal 50 grain coming out the highest at 0.053 BC. So if someone has a 30 cal rifle and if shot count or cost is not an issue and if only accuracy is, wouldn't they choose the 0.053 and just tune the gun to shoot it best?
Secondly, if you look at the velocity of the JSB exact 44.7 gr in the link "Hard Air Magazine", why is the 30 yard velocity at 782 fps which is much more higher than the 0.25 cal JSB Exact King Heavy MK II 33 gr, at only 603 fps at 30 yards?
It was all shot out of the same gun and I see an outlier here. Why am I asking this question?
The BC equation suggests, the higher the velocity, the better BC due to the velocity in the numerator. However there are other factors like harmonics. Let's just start with the first two questions and then proceed form there.
Thanks,
Jai