How to use a Ballistics Program
07-02-2008 | 08:03 PM
#21
Nontypical Buck
Joined: Mar 2005
Posts: 1,392
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From: Renfrew County, Ontario, Canada
RE: How to use a Ballistics Program
Point Blank is the one I use as well. I read, I believe it was a Chuck Hawks article, that true BC could be found by doing a close measurement and a far one. I'll see if I can find it and post a link to it.
The fact that the numbers proved out gives me the confidence to believe in the tables and by extension, that particular load. I was shooting Nosler Partitions when I did that test.
The fact that the numbers proved out gives me the confidence to believe in the tables and by extension, that particular load. I was shooting Nosler Partitions when I did that test.
07-02-2008 | 08:05 PM
#22
Nontypical Buck
Joined: Mar 2005
Posts: 1,392
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From: Renfrew County, Ontario, Canada
RE: How to use a Ballistics Program
07-03-2008 | 05:20 AM
#23
Thread Starter
Nontypical Buck
Joined: Dec 2005
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From:
RE: How to use a Ballistics Program
http://www.chuckhawks.com/bc.htm
Chap
07-03-2008 | 10:49 AM
#24
Nontypical Buck
Joined: Jan 2008
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From:
RE: How to use a Ballistics Program
Actually, you don't even need the BC -- it is a relatively meaningless and soft number (changes with velocity etc). I have seen few on the internet for ML bullets that generated accurate trajectories with what I saw on the range.
I take a slightly different approach. I get my muzzle velocity, zero the gun at normal range, then check the actual drop at a second range. For example, last summer I zeroed my new scope at 100 yards, getting my MV off the chrony, then aimed dead-on at 200 and shot another nice, tight group. I measured the drop from point-of-aim then went back to the ballistics program and entered a 100-yd zero, my MV, and my best guess for BC. I then adjusted the BC entry until the trajectory the program spit out for 200yd matched what I had just shot on the range. Remember, what is important is an accurate prediction of trajectory, not that the BC you use matches any reported BC for that bullet; BC is only a means to an end.
Low and behold, when I went back out and shot at 300 yds I was withing 1/2 MOA of what the program predicted. I was about 3/4 MOA off at 400 yds I think -- more than enough to get on the paper and adjust.
A ballistics program is NEVER a substitute for actually shooting at every range you plan on shooting at game with a ML. For whatever reason I find that the programs are usually spot-on for centerfire but not as reliable for ML predictions.
I take a slightly different approach. I get my muzzle velocity, zero the gun at normal range, then check the actual drop at a second range. For example, last summer I zeroed my new scope at 100 yards, getting my MV off the chrony, then aimed dead-on at 200 and shot another nice, tight group. I measured the drop from point-of-aim then went back to the ballistics program and entered a 100-yd zero, my MV, and my best guess for BC. I then adjusted the BC entry until the trajectory the program spit out for 200yd matched what I had just shot on the range. Remember, what is important is an accurate prediction of trajectory, not that the BC you use matches any reported BC for that bullet; BC is only a means to an end.
Low and behold, when I went back out and shot at 300 yds I was withing 1/2 MOA of what the program predicted. I was about 3/4 MOA off at 400 yds I think -- more than enough to get on the paper and adjust.
A ballistics program is NEVER a substitute for actually shooting at every range you plan on shooting at game with a ML. For whatever reason I find that the programs are usually spot-on for centerfire but not as reliable for ML predictions.
07-03-2008 | 02:19 PM
#25
Nontypical Buck
Joined: Aug 2005
Posts: 1,081
Likes: 0
From: New Mexico
RE: How to use a Ballistics Program
I agree with you Spaniel. If I'm working with a bullet that I don't have a BC for refrence I will sight in and then shoot at another distance and use the ballistics calculator to find the approximate BC as you did. I had to do that with the No Excuse 460's when I first started testing them. As you said, BC is somewhat fluid and a change of .01 or .02 makes little difference in calculated results within normal hunting ranges, many other factors will affect the bullet more thana small mistake in the BC of the bullet. As stated actual range results are the final word on the trajectory of a load, theprogram is just helping you predict and visualize the expected trajectory.
Chap,
I never thought about the ease of use of the Point Blank program as it was easy enough to use as it was. I do believe there are some instructions in the help screen if they are needed. It also has a firearm database to document all your guns if you want to use it. There are also some lists of bullets and there specs as well as some other things that I've never looked at included.
Chap,
I never thought about the ease of use of the Point Blank program as it was easy enough to use as it was. I do believe there are some instructions in the help screen if they are needed. It also has a firearm database to document all your guns if you want to use it. There are also some lists of bullets and there specs as well as some other things that I've never looked at included.
07-03-2008 | 04:31 PM
#26
Thread Starter
Nontypical Buck
Joined: Dec 2005
Posts: 3,246
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From:
RE: How to use a Ballistics Program
ORIGINAL: spaniel
Actually, you don't even need the BC -- it is a relatively meaningless and soft number (changes with velocity etc). I have seen few on the internet for ML bullets that generated accurate trajectories with what I saw on the range.
I take a slightly different approach. I get my muzzle velocity, zero the gun at normal range, then check the actual drop at a second range. For example, last summer I zeroed my new scope at 100 yards, getting my MV off the chrony, then aimed dead-on at 200 and shot another nice, tight group. I measured the drop from point-of-aim then went back to the ballistics program and entered a 100-yd zero, my MV, and my best guess for BC. I then adjusted the BC entry until the trajectory the program spit out for 200yd matched what I had just shot on the range. Remember, what is important is an accurate prediction of trajectory, not that the BC you use matches any reported BC for that bullet; BC is only a means to an end.
Low and behold, when I went back out and shot at 300 yds I was withing 1/2 MOA of what the program predicted. I was about 3/4 MOA off at 400 yds I think -- more than enough to get on the paper and adjust.
A ballistics program is NEVER a substitute for actually shooting at every range you plan on shooting at game with a ML. For whatever reason I find that the programs are usually spot-on for centerfire but not as reliable for ML predictions.
Actually, you don't even need the BC -- it is a relatively meaningless and soft number (changes with velocity etc). I have seen few on the internet for ML bullets that generated accurate trajectories with what I saw on the range.
I take a slightly different approach. I get my muzzle velocity, zero the gun at normal range, then check the actual drop at a second range. For example, last summer I zeroed my new scope at 100 yards, getting my MV off the chrony, then aimed dead-on at 200 and shot another nice, tight group. I measured the drop from point-of-aim then went back to the ballistics program and entered a 100-yd zero, my MV, and my best guess for BC. I then adjusted the BC entry until the trajectory the program spit out for 200yd matched what I had just shot on the range. Remember, what is important is an accurate prediction of trajectory, not that the BC you use matches any reported BC for that bullet; BC is only a means to an end.
Low and behold, when I went back out and shot at 300 yds I was withing 1/2 MOA of what the program predicted. I was about 3/4 MOA off at 400 yds I think -- more than enough to get on the paper and adjust.
A ballistics program is NEVER a substitute for actually shooting at every range you plan on shooting at game with a ML. For whatever reason I find that the programs are usually spot-on for centerfire but not as reliable for ML predictions.
07-03-2008 | 04:33 PM
#27
Thread Starter
Nontypical Buck
Joined: Dec 2005
Posts: 3,246
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From:
RE: How to use a Ballistics Program
ORIGINAL: dmurphy317
I agree with you Spaniel. If I'm working with a bullet that I don't have a BC for refrence I will sight in and then shoot at another distance and use the ballistics calculator to find the approximate BC as you did. I had to do that with the No Excuse 460's when I first started testing them. As you said, BC is somewhat fluid and a change of .01 or .02 makes little difference in calculated results within normal hunting ranges, many other factors will affect the bullet more thana small mistake in the BC of the bullet. As stated actual range results are the final word on the trajectory of a load, theprogram is just helping you predict and visualize the expected trajectory.
Chap,
I never thought about the ease of use of the Point Blank program as it was easy enough to use as it was. I do believe there are some instructions in the help screen if they are needed. It also has a firearm database to document all your guns if you want to use it. There are also some lists of bullets and there specs as well as some other things that I've never looked at included.
I agree with you Spaniel. If I'm working with a bullet that I don't have a BC for refrence I will sight in and then shoot at another distance and use the ballistics calculator to find the approximate BC as you did. I had to do that with the No Excuse 460's when I first started testing them. As you said, BC is somewhat fluid and a change of .01 or .02 makes little difference in calculated results within normal hunting ranges, many other factors will affect the bullet more thana small mistake in the BC of the bullet. As stated actual range results are the final word on the trajectory of a load, theprogram is just helping you predict and visualize the expected trajectory.
Chap,
I never thought about the ease of use of the Point Blank program as it was easy enough to use as it was. I do believe there are some instructions in the help screen if they are needed. It also has a firearm database to document all your guns if you want to use it. There are also some lists of bullets and there specs as well as some other things that I've never looked at included.
