Page 8 of 8 FirstFirst ... 678
Results 71 to 74 of 74

Thread: Uber-tight upper:lower fit, how to loosen?

  1. #71
    Join Date
    Jul 2009
    Location
    Left Coast
    Posts
    914
    Feedback Score
    4 (100%)
    Rob,

    I've had two LB uppers with the same exact problem. The pins were hammer tight on both regarless of the lower. What I used to open up the holes was labor intensive, but it worked. I erred on the side of caution and enlarged the holes by hand using, at first, 400 grit wet-dry paper rolled in a tube shape. Moving the sandpaper in and out while rolling the paper tube was effective, but took hours. For the second one, I started with 220 grit wrapped around a long roll pin punch as it was more rigid for sanding. I then moved to 300, 400, and finished with 600 grit and some polishing compound.

    The takedown/pivot pins function normally on both now, but the odd thing is that I can't interchange them, i.e., when I do they're too damn tight on other lowers.

  2. #72
    Join Date
    Nov 2009
    Posts
    19
    Feedback Score
    0
    Glad I'm not the lone ranger on this. I have a LB upper and I need a brass hammer to get it in the old pwa lower I'm using. I'm thinking now it is easier to use a RRA 9mm upper and have the tube hole drilled. Works great on all my lowers, even CAV lowers. No brass deflector hump either. I just can't go from slick side A1 uppers to flattops with crap on the side. This would be easier if I wouldn't have seen the the RDS light.

  3. #73
    Join Date
    Apr 2008
    Posts
    162
    Feedback Score
    0
    I have a several year old noveske lower I finally got around to building up. the fit with it on my sr15 upper which I am using on it was horrifically tight. Rather than modify the receivers which are expensive pieces I just sanded down the rear takedown pin by hand with some 400 grit sand paper. it still fits pretty tight but the pin is easily removed using a round as a punch.
    Last edited by yallknowho; 09-06-11 at 16:41.

  4. #74
    Join Date
    Apr 2007
    Location
    FL
    Posts
    9,246
    Feedback Score
    28 (100%)
    Rob, I guess I'll go ahead and ask (as you have posted previously that you already solved the problem) what method you used and your general opinion of the method.
    Tools, time, effectiveness, that kind of thing. After all, it isn't much of a help thread if the reader doesn't know who to trust and who to disregard.
    Jack Leuba
    Director, Military and Government Sales
    Knight's Armament Company
    jleuba@knightarmco.com

Page 8 of 8 FirstFirst ... 678

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •