Check how hard its shooting by knocking thru soup cans, bars of detergent soaps and a beer bottle. Try it out at various ranges and you will get a fair idea. The pellets b.c. was and is available on the net as I was using some well known stuff. In this case the very popular Crosman Premiers in .22. After all I ran as far as I could from maths after class 10. ;-)So its nuthing that I had to come up with.
Dev
All about FPS!
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Sid_kapur30
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tarat
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Re: How do we check an air rifles fps
Hiya ,
A chrony is your best bet as all have indicated. A few months ago, I had posted a question on how to get a chrony, legal issues etc. Well, it needs to be imported so I'm not sure of the state of health it'll arrive in, so I dropped the idea. The POA-POI (drop) method is tricky and is more of a 'calculation' than a 'measurement' While I am game for any calculations, there are too many variables that affect trajectory, so I am not comfortable with this calc.
Next thing I tried was a music editing software called Audacity (free download) I used my digital camera to record a clip of a shot taken at a known distance, at a metallic target to create a sharp 'clang' I transferred the file to my comp. and ran it on Audacity waveform analysis. Was expecting two tall spikes amidst a bunch of shorter ones. The idea was to time stretch the waveform to get the time interval between the shot and the impact. Distance was known so velocity could be reasonably calculated. But ..... the damn waveform turned out full of almost equally tall spikes. Bummer ! Racked my head inside inside out and finally gave up as it was become too complex to perform accurately.
And then .... I found out a software (free) from the Talontunes forum. This uses EXACTLY the same principle that I was trying to work with developed by a guy at Talontunes. Someone's a little smarter than I am
The sound input is via a microphone. I downloaded it and ran a test today. Results didnt look convincing to me but I think thats my error because forumites (from Talontunes) have reported acceptable measuring accuracy. Basically I was doing the test indoors (mortally scared of taking my gun outside) and this causes echo problems. Also the range becomes too short for the software. My airpistol registered 605, 602 and 595 fps on 3 consecutive shots which is too fast IMO.
Will test some more .... lets see
Regards
RT
A chrony is your best bet as all have indicated. A few months ago, I had posted a question on how to get a chrony, legal issues etc. Well, it needs to be imported so I'm not sure of the state of health it'll arrive in, so I dropped the idea. The POA-POI (drop) method is tricky and is more of a 'calculation' than a 'measurement' While I am game for any calculations, there are too many variables that affect trajectory, so I am not comfortable with this calc.
Next thing I tried was a music editing software called Audacity (free download) I used my digital camera to record a clip of a shot taken at a known distance, at a metallic target to create a sharp 'clang' I transferred the file to my comp. and ran it on Audacity waveform analysis. Was expecting two tall spikes amidst a bunch of shorter ones. The idea was to time stretch the waveform to get the time interval between the shot and the impact. Distance was known so velocity could be reasonably calculated. But ..... the damn waveform turned out full of almost equally tall spikes. Bummer ! Racked my head inside inside out and finally gave up as it was become too complex to perform accurately.
And then .... I found out a software (free) from the Talontunes forum. This uses EXACTLY the same principle that I was trying to work with developed by a guy at Talontunes. Someone's a little smarter than I am
The sound input is via a microphone. I downloaded it and ran a test today. Results didnt look convincing to me but I think thats my error because forumites (from Talontunes) have reported acceptable measuring accuracy. Basically I was doing the test indoors (mortally scared of taking my gun outside) and this causes echo problems. Also the range becomes too short for the software. My airpistol registered 605, 602 and 595 fps on 3 consecutive shots which is too fast IMO. Will test some more .... lets see
Regards
RT
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biking3819
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Re: How do we check an air rifles fps
thanx tarat for sharing the info about the softchrono.
cheers sanjiv
cheers sanjiv