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John MH

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Posts posted by John MH

  1. I think the term used these days by the liberal elite is you have to be 'woke'.

    In its modern-day, politicised context, 'woke' is defined by the OED as 'originally: well-informed, up-to-date. Now chiefly: alert to racial or social discrimination and injustice'.

    Or IMHO the ability to be offended by everything and be the excuse used to shut down debate, particularly from the left leaning snowflakes, when it does not fit their polarised agenda.

  2.  

    Food for though 🙂

     

    Annual deficit:

    Lab 2010: £153.5bn

    Con 2019: £32.3bn

     

    NHS Budget:

    Lab 2010: £111.7bn

    Con 2019: £139.3bn

     

    Minimum Wage:

    Lab 2010: £5.93

    Con 2019: £7.70

     

    Tax Free Allowance:

    Lab 2010: £6,475

    Con 2019: £12,500

     

    Unemployment:

    Lab 2010: 8%

    Con 2019: 3.9%

  3. 2 minutes ago, Popsbengo said:

     It's not surprising that the UKV demographic is heavily Tory.  My guess is predominately over 50, white males into country sports  🤔

    Well, I'll buck the trend I think.  I'll hold my nose and vote for anyone but the Serial Lying Buffoon and his cabinet of self-serving weaklings and nasty thick Little Ingurlanders.

    So you are happy to give up your .308 Win and .338 Lapua?

  4. 1 hour ago, BlueBoy69 said:

    I extensively used Doppler radars as part of a suite of ballistic instrumentation for one of my previous jobs. The biggest problem with Dopplers, after being able to detect the projectile for long enough, is triggering. Get that wrong, especially with high-drag projectiles which small arms generally are, and you can give up trying to get decent muzzle velocity results, or results at all. Bad triggering is more than likely the problem that is occurring here with these small-calibre high-drag projectiles.

    The Labradar is normally triggered by acoustic noise (pressure), or a change (increase) in the Doppler signal. The Labradar has three acoustic triggers, the inbuilt high noise level one, plus two external ones, the air-gun trigger and the archery trigger. The inbuilt should work with most unsuppressed guns, the air-gun trigger for air-guns and suppressed guns, and the archery trigger is self-explanatory.

    For acoustic triggering, this is something we never used as it was generally impractical on big guns as it was too variable and hence impossible to get the precise muzzle exit times. Precise muzzle exit is required for accurate muzzle velocity prediction, especially on high-drag projectiles and when measuring automatic weapons. A piezo pressure gauge fitted near the muzzle, which would require a hole to be drilled and tapped, was a good pressure trigger but obviously totally impractical for many weapons for many reasons.

    Doppler triggering, which is generally caused by the high-pressure propellant gases venting or the projectile as it enters the beam, was used for simpler Doppler systems we used and the error with low-drag projectiles was acceptable. For small arms, their drag is so high in comparison to larger projectiles that a slight error in what is perceived to be muzzle exit will result in an incorrectly calculated muzzle velocity. Also, if the trigger is late and the Doppler low powered, the projectile can be out of detectable range before measurement can occur.

    It should be noted that precise muzzle exit times are only required for muzzle velocity prediction, not the measurement downrange. Saying that, a good muzzle exit trigger is required so that the said measurement can at least take place. If the trigger is late and the projectile is out of the beam, or its reflected signal is too weak, you’re not going to get anything.

    For me, the Labradar falls down in a number of ways, the first of which is its power supply which is abysmal. It should have a far better battery power system, such as an external battery pack as standard with nothing internal, and an external mains power supply system. It could certainly do with a better non-contact muzzle exit detector, such as a flash detector. It could do with the ability to set the offset distances of the acoustic trigger, to the side and backwards and forwards, so geometric correction of the trigger and Doppler can be made. It would be nice to be able to do some post-analysis, so the ability to save of the digitised raw Doppler signal, or whatever else it might be able to saved, would be nice. The standard tripod is lacking and the aiming ability isn’t very good either, but over the ranges, it works over, probably not much of a problem.

    And as an afterthought, well comment, if you want to know the 'muzzle velocity', get an in-bore Doppler, radar or laser. Muzzle velocity is a bit of a misnomer anyway as the bullet is still being accelerated by the existing propellant gases for a few projectile calibres anyway, so the peak velocity isn’t at the muzzle!

    Have you been able to do any performance comparisons between a UK/EU Labradar model and a US Spec model?

  5. On 12/2/2019 at 3:21 PM, cheshirelad said:

    Don't suppose anyone knows where there might be a second hand system for sale.

    Unlikely to get a full kit but I have a V2 thrower with Area 419 upgrades and a V1 trickler lying around at home, all that is missing is the stepper motors which you would have to procure yourself, these are generic items available from many sources on the www but you would need to clarify which type to get from Adam McDonald. Working away at the moment but should be home just before Christmas. You would still need to get the scale.

  6. 1 hour ago, No i deer said:

    There is more than one video and that A&D&AT is a monstrosity and was a piece out of that Delorean from the back to the future film which also became part of the mouse trap game 😉😂. The matchmaster is a far better looking piece of technology rather than a contraption 🤪😂.

    Luddite 

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