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Thread: something intresting to crosman collectors

  1. #1
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    something intresting to crosman collectors

    got given an old 761xl today not one of crosmans finest designs and needs the check valve replacing but this is the Whaley conversion which have a very naff reputation but to me very collectable
    I was sent it as I've been putting together a bulkfill co2 rifle like the early 113
    but using the sideplates from a 761 and as I haven't many of the needed parts this will enable me to make brass copies of the plastic cocking parts
    I know the Whaleys were based on 1400/140 tubes pump levers and valve parts but this has a brass tube and certainly not a 140/1400 lever so might be a custom tube or one based on an earlier crosman pumper like a 120 i'll know more when I rebuild her

  2. #2
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    Dec 2016
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    2,061
    stripped her last night and found the build quality of the tube where the valve is secured less than I like and the front valve fixing sheared and a bit too close to the valve o ring
    this I can resolve by using a later 766 valve rear which is longer but i'll machine it down so it's .080" longer than the 1377 valve body they've used
    internally I swapped the valve stem for a later 1377 stem and fitted a longer early type check valve and spring to increase valve pressure and lower the amounts of pumps needed
    when I chrono'd her I'm getting 10 fpe on 8 pumps with a bit of air retention on 9 pumps the velocity drops as the hammer spring isn't stong enough to open the valve fully
    with a bit f messing I imagine I can set it like my blue streak which gives two shots at 11fpe on 8 pumps but would need more than 8 pumps
    I may fit a .22 barrel but would have to detune quite a bit
    it needs a new cocking block as it's worn so i'll set to and make a couple but will make the probe so it screws in that way I can easily change calibre and will make the cocking bolt a bit more robust
    the other problem I see is that the barrel is not securely fixed to the tube at the rear so the addition of bands will help accuracy and this omission of rear barrel stability is why they had such a crap reputation for accuracy
    http://i1341.photobucket.com/albums/...psbkb0adap.jpg

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