close

Privacy guaranteed - Your email is not shared with anyone.

Changing upper reciever

Discussion in 'GATE AR-15 Forum' started by faceplant, Apr 30, 2010.


  1. faceplant

    faceplant
    Expand Collapse

    Joined:
    Feb 8, 2006
    1,493
    410
    I have a Colt H-BAR with carry handle. I will be changing out the upper reciever for a flat top keeping the 20in barrel. I have ordered an upper assembly with parts but no bcg as I will be using the colt bcg. Do I need to check the chamber or will it be adjusted already?
    Thanks
     

    Wanna kill these ads? We can help!
  2. Constructor

    Constructor
    Expand Collapse
    Moderator

    Joined:
    Dec 10, 2009
    552
    5
    Location:
    Roaming
    If you keep the same bolt and barrel combination the headspace will not change so you are good to go.
     

  3. faceplant

    faceplant
    Expand Collapse

    Joined:
    Feb 8, 2006
    1,493
    410
    So your saying that if I get an extra BCG say from Bravo Company that I would not be able to use it in different ARs without worrying about headspace?
     
  4. Constructor

    Constructor
    Expand Collapse
    Moderator

    Joined:
    Dec 10, 2009
    552
    5
    Location:
    Roaming
    Most bolts are close and will not pose a problem but CMT/Stag are known to be on the large side, LMTs are known to be on the small side. If you use a Stag bolt in a LMT barrel most will be tight headspace, use a LMT bolt in a Stag/CMT barrel and there will more than likely be too much headspace. I have no idea who BCM buys their bolts and carriers from.
    Also swapping back and forth is not a good idea because the lugs of the bolt get mated to the lugs of the extension, they should be flat but nothing is perfect. I would buy a bolt for each barrel and keep them together.
     
  5. faceplant

    faceplant
    Expand Collapse

    Joined:
    Feb 8, 2006
    1,493
    410
    Thanks
     
  6. faceplant

    faceplant
    Expand Collapse

    Joined:
    Feb 8, 2006
    1,493
    410
    I changed out the upper reciever. The gas tube was big pain in the backside. I had to use a set of pliers to grip it and bang that with a hammer. Any tips for the next one?
     
  7. Constructor

    Constructor
    Expand Collapse
    Moderator

    Joined:
    Dec 10, 2009
    552
    5
    Location:
    Roaming
    installing the gas tube in the gas block, including the roll pin?
    They make a GB jig, little plastic tray but, I just lay the GB in the vise align the hole and use a roll pin starter. It looks like a long punch but has a hole in the end to hold the roll pin. Then slide the assembly over the barrel and through the hole in the receiver.
     
  8. faceplant

    faceplant
    Expand Collapse

    Joined:
    Feb 8, 2006
    1,493
    410
    Getting it out of the front site post while taking it apart.
     
  9. Constructor

    Constructor
    Expand Collapse
    Moderator

    Joined:
    Dec 10, 2009
    552
    5
    Location:
    Roaming
    If I have to pull them apart I clamp the tube in a vise and pull the f-sight base or gas block off.