Barrel length

Discussion in 'Hunter (HFT) & Field Target (FT)' started by roger, Sep 7, 2015.

  1. roger

    roger old git

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    I havejust put a longer barrel on one of my Pro Target rifles can anyone help with the question below:confused:
    Will this increase the muzzle velocity? or decrease the muzzle velocity?
     
  2. BDL

    BDL Dangerous

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    It will increase the velocity

    Bri
     
  3. roger

    roger old git

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    Many thanks that is what i have been told. thanks for the confirmation:)
     
  4. Ceathreamhnan

    Ceathreamhnan WHFTA Champion 2013

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    A longer barrel is more efficient - for the same amount of air coming out of the firing valve, the pellet will accelerate for longer before leaving the barrel.
     
  5. roger

    roger old git

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    Many thanks for the explanation i understand the principle now
    Roger:lev
     
  6. luddite

    luddite I Love HFT

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    The downside is that you will need to hold aim for longer as the lock time will increase. :shot:
     
  7. roger

    roger old git

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    Thanks for that tip definatley one to consider
    Roger:lev
     
  8. Darron

    Darron Reformed Bandit

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    The lock time will increase but by an absolute nano second. Good follow through technique is a pre requisite of good shooting with any barrel length
     
  9. Tench

    Tench WHFTA World Champion 2016.

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    I have found that you cant generalise and say it will increase velocity, it probably will but it depends on other factors too, if the firing valve is still open when the pellet leaves the barrel then yes it will increase the velocity. But if the valve is closed before the pellet left the original shorter barrel then a longer barrel can lower the velocity. I have seen velocities go up when reducing 19" pcp barrels to 16".
     
  10. roger

    roger old git

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    Thanks to all for your informative replies
    Roger:)
     
  11. Adam

    Adam Active Member

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    Yes...
    by approximately 1 millisecond for an extra ten inches. :lev
     
  12. luddite

    luddite I Love HFT

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    As much as that??? :eek:
     
  13. Jon

    Jon Member

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    Depends what barrel your putting on as well have seenBSA of old and bog standard spec 24" Lothars give 130ft/sec slower than CZ at 17".
    Also shortening properly may increase velocity or lower more usual.

    Only way is see what happens.
     
  14. roger

    roger old git

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    I have gone from 17 inch to 23 inch lost 20fps but could adjust back to 770 tightend up the grouping and made me concentrate more on the follow through.
    Thanks to all who responded to this question.
    Roger:)
     
  15. tillygti6

    tillygti6 Tilly's gun stocks

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    Funny things barrels, I have a ev2 barrel at 13.5" ish and it groups better now than it did at 16" and is more air efficient in MY gun at the shorter length.
    Must be magic or something tench does to them?
     
  16. Tench

    Tench WHFTA World Champion 2016.

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    Just goes to show that the ideal barrel length for best efficiency in a particular gun is one that matches the pellet weight and valve duration, a barrel that is longer or shorter can be less efficient.
     

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