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Thread: HW77 .177 transfer port size

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  1. #1
    Snooper601 is offline I likes to polish my trophy
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    Just make sure the gurb screw length is the same as the port length to save making any extra lost volume.

    Cheers

    John
    Snooper601 Suspect a simple fault, or a simple engineer He who dies with the most toys wins!
    QHAC Official lubricant development engineer.

  2. #2
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    Quote Originally Posted by Snooper601 View Post
    Just make sure the gurb screw length is the same as the port length to save making any extra lost volume.

    Cheers

    John
    Thanks John

    I was worried about the actual Allen key hole, would this not cause problems?

    Cheers
    B

  3. #3
    Snooper601 is offline I likes to polish my trophy
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    As Tony says above, make them flush at both ends.
    The slight lost volume due to the Allen recess is only slight and is like putting a pellet with a deeper skirt in the barrel, probably less than the 0.1mm size difference in the drilled holes, though it may be a bigger difference on a short transfer port.

    Cheers

    John
    Snooper601 Suspect a simple fault, or a simple engineer He who dies with the most toys wins!
    QHAC Official lubricant development engineer.

  4. #4
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    There was a very early 20th century, pre first world war, trade magazine called Arms and Explosives? I read an article in an edition which detailed in several pages experiments carried out by BSA using the Lincoln Jeffries patent underlever rifles they were making at the time. They experimented with light and heavy pistons eventually settling on the heavy for best overall performance in their production air rifles.

    "an early 1900s rifle (can't remember the make/model right now), where the maker fitted an aluminium piston in the target version to reduce recoil."

  5. #5
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    the difference now is in an age of sharing, before 99% was all kept secret, so even though 99% has been done before it really is all new as before most was never released.

    Ask Jb if he will share all his secrets....report back to us what he says

    the gun trade is very secretive.....

  6. #6
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    "the gun trade is very secretive...."

    Read my previous post again.



    There was a very early 20th century, pre first world war, trade magazine called Arms and Explosives? I read an article in an edition which detailed in several pages experiments carried out by BSA using the Lincoln Jeffries patent underlever rifles they were making at the time. They experimented with light and heavy pistons eventually settling on the heavy for best overall performance in their production air rifles

    That doesn't sound very secretive to me
    As well as I can remember JB gave details in Airgun World of what he did in his air rifle conversions including information about piston heads, weights transfer port sizes, barrel locks, adjustable hinge bolts etc. Is there anything specific you want me to ask him tomorrow? Why don't you ring him and seek his advice yourself? It would save me the cost of a phone call

  7. #7
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    Quote Originally Posted by greenwayjames View Post
    "the gun trade is very secretive...."

    Read my previous post again.



    There was a very early 20th century, pre first world war, trade magazine called Arms and Explosives? I read an article in an edition which detailed in several pages experiments carried out by BSA using the Lincoln Jeffries patent underlever rifles they were making at the time. They experimented with light and heavy pistons eventually settling on the heavy for best overall performance in their production air rifles

    That doesn't sound very secretive to me
    As well as I can remember JB gave details in Airgun World of what he did in his air rifle conversions including information about piston heads, weights transfer port sizes, barrel locks, adjustable hinge bolts etc. Is there anything specific you want me to ask him tomorrow? Why don't you ring him and seek his advice yourself? It would save me the cost of a phone call
    you think jb would talk to me lol.....dream on man...in fact I would not dream of asking him as I prefer to make my own notes.

    you seem quite hostile with me, I think it best we do not comment on each others posts going forward, we do not want to upset the admin now.

    I respect your opinion, please respect I have my own too, if I offer advice its up to the in decidual if they choose to except it or not.

    thank you

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