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    FBI Sniper Rifles

    I pray you are right.
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    Garmin Xero C1 Pro chronograph

    I saw better agreement when running a Magnetospeed at the same time as a Garmin. Don't know what caused the disagreement in the photos. That can happen with any instrument. It is the reason I run two whenever making important measurements. IF they are in good agreement, everything is...
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    Garmin Xero C1 Pro chronograph

    Skyscreen chronographs measure velocity midway between the "start" and "stop" screens (no offense intended, you probably know this but there may be some readers that don't). I think the start screen was 9.5 feet. I was using a 9 foot spacing so the point the Oehler was measuring velocity would...
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    Garmin Xero C1 Pro chronograph

    Best I can tell, the Garmins do as good a job of measuring muzzle velocity as most anything. I believe they interpolate a MV from measuring in front of the muzzle because they can't measure right at the muzzle. To investigate, I ran a 20 round test on an Oehler 35P with a 9' spacing. That...
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    FBI Sniper Rifles

    Pictures, artwork, etc., that's how some were concealed.
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    FBI Sniper Rifles

    The weapons display was removed a long time before you went thru the Academy. If I had to guess, I'd say about 2,000. That display attracted a lot of attention and many visitors would linger in the gun cleaning room to view it. There were a few NDs in that room and it was decided that...
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    FBI Sniper Rifles

    The rate at which the Possible Club grew declined significantly when the FBI moved from teaching precision shooting to teaching speed shooting. If you want a good idea of how slowly it has filled, go look at the board and find my name, JB BOONE. I shot it in October of 1988.
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    The Wheel of Time

    Time Of Flight is the most important factor in long range accuracy. Drop? TOF based. Wind deflection? TOF based. Shooters think in terms of distance. Ballistic programs convert TOF to distance. One day shooters will seek TOF consistency in the same way they now seek MV consistency.
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    2024 Christmas gift thread (#2)! Please read instructions to participate!

    M40
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    Key holing 6mm creed after barrel cut

    Publishing was encouraged for our Engineering Technician, Ballistics guy: https://www.longrangehunting.com/articles/the-over-rated-crown.670/
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    Which piece of equipment is more important?

    I've seen a few from AB. I got a call from Bryan to let me know his video showed barrel movement. I reminded him that mine did, too. Only the movement is straight to the rear. The dial indicator was to measure vertical, which was not observable prior to bullet exit (I've only ever heard...
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    Which piece of equipment is more important?

    Nope, incorrect. "Reliable" chronographs have been around since the 70s. Perhaps they were not convenient but they were certainly reliable. BTW, you are not the only one to make this error. I've heard two or more, highly respected, people say the same thing.
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    Barrel rifling

    I looked the Shot Marker up and it certainly seems to be a good piece of kit. In the spirit of "Trust but verify", have you ever put a Garmin or other chronograph downrange to verify the Shot Marker is giving a reliable velocity measurement?
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    Barrel rifling

    Drag consistency has been discussed more in recent months than I can recall in many years. The average consumer now has the ability to actually measure it without "breaking the bank". Two Garmins will give you a MV and a downrange velocity. Hard part is shooting within the appropriate place...
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    Garmin xero or ab mobile wrong?

    I've never found a radar measured drag function done by a competent source to be "Goofy". They offer the most accurate description of drag available - but for the "system" (rifle and bullets) that was actually shot over the radar. Shoot the same bullets in a different barrel and your results...
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    Measuring the velocity of the bullet a target distance

    I should have specified that I meant very few 10 second radar tracks in the civilian world. I get that there are military (therefore Government) entities that have long range radar systems. Most of the radar data available to civilians, for civilian bullets, were done by private entities.
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    Measuring the velocity of the bullet a target distance

    There are few, very few radar measurements of 10 seconds. That takes a multi-head, tracking system. Likely only possessed by government labs. The 10 second limit was set to give "room to grow". When testing into subsonic with the System '89 a target has to be impacted to trigger the...
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    Measuring the velocity of the bullet a target distance

    Unless you are planning on using that data to shoot at a distance where you'll have a TOF of 10 seconds :). I used that example simply to show that, no matter what capability is offered, someone will ask for more. The best use of deriving a single BC from TOF would be on a radar measured drag...
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    Measuring the velocity of the bullet a target distance

    Yes, kind of. The '89 measures time of flight (TOF) and will report BC in multiple drag functions. Some target configurations report velocity at the target but it is a calculated velocity based on a measured TOF and the drag function you chose. Changing drag functions can (usually will)...
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    Measuring BC - Oehler '89

    Both MV ES and drag (BC) ES contribute to vertical dispersion. Most shooters have not had an affordable method of measuring drag ES. The '89 changed that though you had to use skyscreens and a long spacing. Now you can ditch the skyscreens and get data with the same level of confidence but...
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