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Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
WildcatBullet 338 cal 350 gr elevation at 2000 yards ???
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<blockquote data-quote="DANTEC" data-source="post: 65949" data-attributes="member: 685"><p>ok more informations</p><p></p><p>first some tipes on the basics of instrumentation /measurement equipement </p><p></p><p>calibration : for every thing /every stuff you use you need to calibrate </p><p>exmple </p><p>a thermometer probe will be dip in a bath od melded ice to check the zeo ( temperature of melted ice in water is a perfect know temperature ) and dip after in boiling water ( same perefcet know temerature , with possible correction with atmospheric pressure I agree ..)</p><p></p><p>so a chrono need to be calibrated with know velocity ammo as realmil specs ammo and/or twin chrono set up ( the second chrono will a be a lac quality one )</p><p></p><p>resoluation if you want/nedd to measure a physical thing the accuracy of your instrument need to be 1/10 of the lowest step you want measure </p><p>to check one inch you need a instrument accurate at 1/10 minimum </p><p>repetability ; you need to check if if you make string of same emasure you get the same result and that step by step if you use a sevreal stage electronic device and software too </p><p></p><p>after these points od details but very important to not measure anything with anything </p><p></p><p>as set up I use to make accurate velocity / TOF measurement </p><p></p><p>I use a counter timer ( not a cheap chinese /taiwan look a like ) a but HP 5334A or a 5335A these xcounter timer can reach 2 nanosecond on 1 event ( burst mode ) </p><p>to trigger these trigger I use a </p><p>a first trigger near th emuzlle made with microphone and a amplifier/trigger interface to get a logic signal and start the HP5334A so the counter timet start to count </p><p></p><p>to stop it I use a pezo disk glue on a pannel ( rest of the target , when bullet hit the traget that create a vibration and the pezo disq generate a tension to command a electronic device to stop the couneter </p><p></p><p>main difficult thing is to find ( or know the time that your trigger signal ) make to come back from 600 yards , to measure this signal I generate with a pulse genrator a pulse at a know frequency in the wire - short range under 150 yards ) or fiber optic over 150 and up to 600 yards and check with a oscilloscope the time of ( delay ) of signal bteween each end of the wire or the optic fiber </p><p>so I can get a resulat as </p><p></p><p>( T(0) as staring time + T ( Imp ) display on the couner ) - time of signal in the wire = TOF </p><p></p><p>by and with a simalr equipement I can fit two panesl with piezo at 1000 yards and check velocity of th ebullet at 1000 yards or evne 1600 yards but I need to let my couneter timer at 1000 or 1600 yards or I can ( I works on ) use a RS232 radio ( wireless ) communication ports to control my counter timer at 1000 yards and read display on my laptop </p><p></p><p>all hardware can be made with surplus stuff purchase on Ebay </p><p>a HP5334a / HP5335a , Racal or a Solartron cost around as 150 USD to 200 USD </p><p>and home made PCB interface is not very costly </p><p>pulse generator on Ebay cost 200 USD</p><p>a 100 Mhz oscilloscope cost 150 USD or you can purchase a 100 Mhz with memory and use it for strain gage pressure system too </p><p></p><p>even if you add a small generator ( Honda brand with inverter ) toatl cost is not amazing at all </p><p></p><p>good shooting </p><p></p><p>DAN TEC</p></blockquote><p></p>
[QUOTE="DANTEC, post: 65949, member: 685"] ok more informations first some tipes on the basics of instrumentation /measurement equipement calibration : for every thing /every stuff you use you need to calibrate exmple a thermometer probe will be dip in a bath od melded ice to check the zeo ( temperature of melted ice in water is a perfect know temperature ) and dip after in boiling water ( same perefcet know temerature , with possible correction with atmospheric pressure I agree ..) so a chrono need to be calibrated with know velocity ammo as realmil specs ammo and/or twin chrono set up ( the second chrono will a be a lac quality one ) resoluation if you want/nedd to measure a physical thing the accuracy of your instrument need to be 1/10 of the lowest step you want measure to check one inch you need a instrument accurate at 1/10 minimum repetability ; you need to check if if you make string of same emasure you get the same result and that step by step if you use a sevreal stage electronic device and software too after these points od details but very important to not measure anything with anything as set up I use to make accurate velocity / TOF measurement I use a counter timer ( not a cheap chinese /taiwan look a like ) a but HP 5334A or a 5335A these xcounter timer can reach 2 nanosecond on 1 event ( burst mode ) to trigger these trigger I use a a first trigger near th emuzlle made with microphone and a amplifier/trigger interface to get a logic signal and start the HP5334A so the counter timet start to count to stop it I use a pezo disk glue on a pannel ( rest of the target , when bullet hit the traget that create a vibration and the pezo disq generate a tension to command a electronic device to stop the couneter main difficult thing is to find ( or know the time that your trigger signal ) make to come back from 600 yards , to measure this signal I generate with a pulse genrator a pulse at a know frequency in the wire - short range under 150 yards ) or fiber optic over 150 and up to 600 yards and check with a oscilloscope the time of ( delay ) of signal bteween each end of the wire or the optic fiber so I can get a resulat as ( T(0) as staring time + T ( Imp ) display on the couner ) - time of signal in the wire = TOF by and with a simalr equipement I can fit two panesl with piezo at 1000 yards and check velocity of th ebullet at 1000 yards or evne 1600 yards but I need to let my couneter timer at 1000 or 1600 yards or I can ( I works on ) use a RS232 radio ( wireless ) communication ports to control my counter timer at 1000 yards and read display on my laptop all hardware can be made with surplus stuff purchase on Ebay a HP5334a / HP5335a , Racal or a Solartron cost around as 150 USD to 200 USD and home made PCB interface is not very costly pulse generator on Ebay cost 200 USD a 100 Mhz oscilloscope cost 150 USD or you can purchase a 100 Mhz with memory and use it for strain gage pressure system too even if you add a small generator ( Honda brand with inverter ) toatl cost is not amazing at all good shooting DAN TEC [/QUOTE]
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