+ Reply to Thread
Results 1 to 5 of 5

Thread: 7mm Sight Base Replacement

Click here to increase the font size Click here to reduce the font size
  1. #1
    Really Senior Member nijalninja's Avatar
    Join Date
    Nov 2017
    Last On
    Today @ 06:38 AM
    Location
    Australia
    Age
    20
    Posts
    336
    Local Date
    12-12-2018
    Local Time
    12:31 AM

    7mm Sight Base Replacement

    G'day there, as usual I am here asking for some wisdom with a repair.

    I have a 7mm Brazillian with a hacked to bits rear sight base, and I also have a new sight base to replace it with. Now I have heard it said by plenty of people that to get it off you need a plumber's torch to heat it up and loosen the solder under the base and in the screw threads (Supposedly Lead Solder), and that you need to take the foresights off before the rear.

    But now the question is: How do you get the new sight base on? As in how do you apply the solder back to it like it was before but with the replacement base? I can't think of a way to get the solder in there evenly.

    Cheers to any help, this will get me one step closer to having my 7mm back to nice condition.

  2. # ADS
    Friends and Sponsors
    Join Date
    October 2006
    Location
    Milsurps.Com
    Age
    2010
    Posts
    All Threads
    No Drill-Tap scope mounts for Mosin Nagant, Mauser K98K, Yugo M48, Swedish M96 and M38, Swiss K31, K11, 1911 and more! Bringing mil-surplus rifles to modern standard without damaging historical values! We specialise in military utensils and artefacts such as helmets, daggers, medals and badges, etc.  The on-line store is intended for personal browsing and searching of collecting objects. All items are provided historical value only and can be used for home collection or other purposes except of fascism, Nazism or other extremism manifestation or its propaganda. LIMITED TIME OFFER FROM THE AMERICAN GUNSMITHING INSTITUTE: Get Immediate Online Access To AGI's NEW Armorer's Course for Glock Pistols, Covering Every Generation of Glocks, Including the Latest Model 42/43 and Double Stack Pistols for ONLY $7.00! Brian Dick ... BDL Ltd. - Specializing in British and Commonwealth weapons Chuck in Denver ... Buy-Sell-Trade .. Guns, Cars Motorcycles We pride ourselves on being the new lowest price listing service, and the simplest to use. If you need to buy or sell collectible firearms or any firearm in your legal possession, then this is the place for you. If you’re a big collector clearing house, or other seller that could benefit from a Premium seller account, then we can also support you here at Armory.Auctions LLC. Your source for the finest in High Power Competition Gear. Here at T-bones Shipwrighting we specialise in vintage service rifle: re-barrelling, bedding, repairs, modifications and accurizing. We also provide importation services for firearms, parts and weapons, for both private or commercial businesses.
     

  3. #2
    Contributing Member rcathey's Avatar
    Join Date
    Dec 2012
    Last On
    Today @ 10:26 AM
    Location
    St. Louis, MO Area
    Posts
    699
    Local Date
    12-11-2018
    Local Time
    10:31 AM
    There’ll likely be a bit still stuck on the barrel.
    When you put the new base on and heat it up, capillary action will wick PLENTY around the barrel to hold the sight on. Wouldn’t take much.
    Just like soldering copper pipe together.

  4. Avoid Ads - Become a Contributing Member - Click HERE
  5. #3
    Member wjw's Avatar
    Join Date
    Nov 2011
    Last On
    Today @ 01:52 AM
    Location
    British Columbia
    Posts
    23
    Local Date
    12-11-2018
    Local Time
    07:31 AM
    To get a good joint one needs to clean the old solder off, flux and tin the area where the sight will fit with just a wash of solder, then flux the inside of the sight and position. Heat the sight and barrel and when hot enough, add solder by touching it to the area where the sight and barrel meet. Capillary action will draw the solder into the joint. Not cleaning and fluxing will at best result in a poor joint and usually causes a mess. Be advised that the flux will remove the finish, so try to only flux the area under the sight.

  6. #4
    Really Senior Member nijalninja's Avatar
    Join Date
    Nov 2017
    Last On
    Today @ 06:38 AM
    Location
    Australia
    Age
    20
    Posts
    336
    Local Date
    12-12-2018
    Local Time
    12:31 AM
    Thread Starter
    rcathey, I have no idea what capillary action is or what it is like soldering copper pipe but I will look it up. Cheers.

    wjw, not sure what flux and tin is but I'll look it up thoroughly. I don't think there will be any finish under the sight base anyway. Thanks a bunch.

  7. #5
    Really Senior Member nijalninja's Avatar
    Join Date
    Nov 2017
    Last On
    Today @ 06:38 AM
    Location
    Australia
    Age
    20
    Posts
    336
    Local Date
    12-12-2018
    Local Time
    12:31 AM
    Thread Starter
    So as I understand it: I have to heat up the front sights to get the solder loose, remove a screw under the blade/dovetail and it should drift off (brass drift), the do almost the same at the rear sights. Then I heat the areas where the sights sat and wipe off the old solder, clean these areas with some kind of solvent (Isopropyl alcohol maybe), then flux the areas on both the barrel and inside the sights, then add a small amount of solder to both the sights and the barrel before mounting the sights, then mount the rear sight base and align it with the screws, then just keep heating the barrel and sight base until the solder melts easily and is absorbed under the base by capillary action, then just let it cool and clean up these areas and replace all screws and whatnot.



    Sound right? Only questions I have are what solder to use (50/50 or 60/40) and what flux to use. If someone can help me there then I am all good to go.

+ Reply to Thread

Similar Threads

  1. Issue with front sight base alignment with rear sight
    By RBruce in forum M16A2/AR15A2 Rifles
    Replies: 2
    Last Post: 03-27-2015, 12:29 PM
  2. Mk II 5* Rear Sight Base
    By Bluenoser in forum The Ross Rifle Knowledge Library Collectors Forum
    Replies: 0
    Last Post: 12-26-2014, 07:49 PM
  3. 1903 sight base
    By Calfed in forum M1903/1903A3/A4 Springfield Rifle
    Replies: 2
    Last Post: 07-24-2010, 06:00 PM
  4. L42 sight mount to fit a replacement sight?
    By deanbombboy in forum The Lee Enfield Knowledge Library Collectors Forum
    Replies: 12
    Last Post: 04-15-2010, 01:47 AM
  5. Rear sight base for Target Sight
    By m1903rifle in forum .22 Smallbore
    Replies: 8
    Last Post: 06-03-2009, 02:02 PM

Tags for this Thread

Posting Permissions

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