Pennsylvania Firearm Owners Association
Page 1 of 2 12 LastLast
Results 1 to 10 of 12
  1. #1
    Join Date
    Mar 2008
    Location
    Lebanon, Pennsylvania
    (Lebanon County)
    Posts
    220
    Rep Power
    642864

    Default AR15 Barrel Swap

    So I got this used complete upper very cheap. I just bought a $50 Bear Creek stainless barrel on sale to replace the original shot out barrel. I just hit a speed bump getting started on the swap. The old barrel has two slots for the pins and the new barrel looks to have a detent for a set screw. It is a fixed carry handle upper so want to stick with the original style sights. Here are pics of what I am working with.
    Thanks for the help.
    Attached Images Attached Images
    Last edited by 65mustang; March 24th, 2018 at 08:03 PM.
    I've got two guns... One for each of ya (Doc Holiday)

  2. #2
    Join Date
    Apr 2009
    Location
    Dillsburg Area, Pennsylvania
    (York County)
    Posts
    2,281
    Rep Power
    3530860

    Default Re: AR15 Barrel Swap

    Easiest and cheapest way would be to purchase one of THESE and reuse the sight post, spring and detent pin from your old sight to complete the swap out. Or take it to a gunsmith and let them locate & cut the new barrel for the taper pins to install your old A2 front sight post. Note: this won't be real cheap.
    Don't believe a word I say and you'll never be disappointed.

  3. #3
    Join Date
    Aug 2010
    Location
    South East of disorder
    Posts
    2,341
    Rep Power
    21474846

    Default Re: AR15 Barrel Swap

    I would just build two new AR's. Its the cheapest way to go
    “Proclaim Liberty throughout all the Land unto all the Inhabitants thereof.

  4. #4
    Join Date
    Mar 2008
    Location
    Lebanon, Pennsylvania
    (Lebanon County)
    Posts
    220
    Rep Power
    642864

    Default Re: AR15 Barrel Swap

    Quote Originally Posted by edritchey View Post
    Easiest and cheapest way would be to purchase one of THESE and reuse the sight post, spring and detent pin from your old sight to complete the swap out. Or take it to a gunsmith and let them locate & cut the new barrel for the taper pins to install your old A2 front sight post. Note: this won't be real cheap.
    Thanks for the help. This looks like the cheapest/easiest way to go.
    I've got two guns... One for each of ya (Doc Holiday)

  5. #5
    Join Date
    Mar 2008
    Location
    Lebanon, Pennsylvania
    (Lebanon County)
    Posts
    220
    Rep Power
    642864

    Default Re: AR15 Barrel Swap

    Quote Originally Posted by Daycrawler View Post
    I would just build two new AR's. Its the cheapest way to go
    This is #3 so I am set for now. Just couldn't turn my back on a $300 complete rifle, but now it looks like it will be $340
    thanks
    I've got two guns... One for each of ya (Doc Holiday)

  6. #6
    Join Date
    Mar 2009
    Location
    Southwest, Pennsylvania
    (Washington County)
    Posts
    1,404
    Rep Power
    21474847

    Default Re: AR15 Barrel Swap

    I'm no pro, but I would be concerned about that setup staying put with just a set screw. I would think a bit of lateral force could torque that tower out of alignment.

    I know people use set screw low pro gas blocks all the time, but those are protected under a handguard.

    Personally, I would at least dimple the barrel and red locktite the set screw. Honestly, I would probably have it pinned. I have heard arfcom'ers mention sending barrels to Adco for similar work.

  7. #7
    Join Date
    Mar 2008
    Location
    Lebanon, Pennsylvania
    (Lebanon County)
    Posts
    220
    Rep Power
    642864

    Default Re: AR15 Barrel Swap

    Quote Originally Posted by marinville View Post
    I'm no pro, but I would be concerned about that setup staying put with just a set screw. I would think a bit of lateral force could torque that tower out of alignment.

    I know people use set screw low pro gas blocks all the time, but those are protected under a handguard.

    Personally, I would at least dimple the barrel and red locktite the set screw. Honestly, I would probably have it pinned. I have heard arfcom'ers mention sending barrels to Adco for similar work.
    There is a dimple in the barrel already and it also clamps in place. It should be ok. Doesn't look to be many options with these.
    thanks
    I've got two guns... One for each of ya (Doc Holiday)

  8. #8
    Join Date
    Jun 2010
    Location
    Next to the Corn
    Posts
    3,826
    Rep Power
    21474848

    Default Re: AR15 Barrel Swap

    The dimple is for a low pro gas block not an FSB. Best thing to do is to have the new barrel drilled and reamed for taper pins. There is a fixture used to ensure the barrel is straight. Adco charges $105 to do the job and install the FSB. If you are going to install an FSB with setscrews, flats should be milled on the barrel.(like in the link below) Some FSBs with set screws are adjustable for fine tuning the sight.

    https://adcofirearms.com/shop/gunsmi...et-screw-fsbs/

  9. #9
    Join Date
    May 2008
    Location
    Bellwood (Tyrone), Pennsylvania
    (Blair County)
    Posts
    563
    Rep Power
    587998

    Default Re: AR15 Barrel Swap

    Use the old front sight base and prepare as shown in the second photo on this page:

    http://www272.pair.com/stevewag/artube/artube2.html

    if possible, have the barrel spotted as shown in the second photo on this page:

    http://www272.pair.com/stevewag/artube/artube3.html

    All of this can be done on a drill press with a vise, although a mill works better.
    I have done this to about 25 Service Rifles used in High Power competition and never had a complaint.
    Steve

  10. #10
    Join Date
    Mar 2008
    Location
    Lebanon, Pennsylvania
    (Lebanon County)
    Posts
    220
    Rep Power
    642864

    Default Re: AR15 Barrel Swap

    Quote Originally Posted by SteveWag View Post
    Use the old front sight base and prepare as shown in the second photo on this page:

    http://www272.pair.com/stevewag/artube/artube2.html

    if possible, have the barrel spotted as shown in the second photo on this page:

    http://www272.pair.com/stevewag/artube/artube3.html

    All of this can be done on a drill press with a vise, although a mill works better.
    I have done this to about 25 Service Rifles used in High Power competition and never had a complaint.
    Steve
    I have all the tools to do this. I will save the old sight in case of a future need. I had already ordered the other sight.
    Thanks for the tip.
    I've got two guns... One for each of ya (Doc Holiday)

Page 1 of 2 12 LastLast

Similar Threads

  1. M1 Carbine Barrel Swap
    By Hooligan in forum Gunsmithing
    Replies: 2
    Last Post: March 10th, 2017, 10:51 PM
  2. barrel swap on ar15
    By djs7795 in forum Gunsmithing
    Replies: 7
    Last Post: April 10th, 2012, 09:44 AM
  3. Sig Sauer barrel swap
    By joe magarack in forum Pistols
    Replies: 0
    Last Post: January 22nd, 2012, 12:27 AM
  4. Remington 870 Barrel Swap
    By Prof. Chaos in forum Gun Pictures
    Replies: 8
    Last Post: December 7th, 2010, 02:49 PM

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
  •  

Local gun shops | Local shooting ranges | Philadelphia Shooting Ranges | Philadelphia Gun Shops | Pittsburgh Shooting Ranges | Pittsburgh Gun Shops