Disassembling-Browning BPS Field Grade 12 ga

Discussion in 'Technical Questions & Information' started by jamone58, Dec 17, 2007.

  1. jamone58

    jamone58 New Member

    Dec 16, 2007
    Disassembling a Browning BPS Field Grade 12 ga

    I own a Browning BPS Field Grade 12 gauge shotgun. I have recently experienced the gun trying to double feed shells, usually at the most inopportune moment. I was told the gun needs to be completely disassembled and thoroughly cleaned. I am looking for complete, step-by-step instructions on how to disassemble the gun (remove the trigger assembly and bolt). I do not want to take it to the local gunsmith because they have screwed up a few guns which friends own. Any help you all can provide would be greatly appreciated.
  2. hlane

    hlane New Member

    Feb 13, 2008

    I dove in last night and earlier this evening came up for air. I've had my BPS Field grade since I was 16, when my dad bought it for me. Fabulous shotgun.

    I hadn't cleaned it in 25 years and it had lots of rounds through it. I can't comment on double loading, but I know mine would occasionally drop a shell out of the magazine while loading the action. Not sure if what I did will remedy the situation, but that's not why I cleaned it. Curiosity got me.

    Last night I didn't know an action bar from a dry spell, but I have a general sense now. Consult a schematic for terms if unfamiliar.

    This is what I did (still had barrel and butt stock on gun, action was closed, gun was upside down, buttstock to my right.):

    Remove trigger pin.

    Tried to remove carrier pin, but it didn't want to go, and at the time I didn't know what it was anyway. It's the smaller pin above the trigger pin running through the gun's receiver.

    (Before you take the trigger out, keep in mind there will be action bars to the left and right of the trigger group. When you take the trigger group out, try and see where the notches are in relation to your receiver. If possible, mark with pencil where the grooves are so that when you go to reassemble, you have a starting point from which to work. This would have helped me greatly I think.)

    Remove trigger by lifting slowly and pulling trigger toward the butt stock.
    As someone elsewhere in cyberspace has said, note which direction the hammer spring pin is oriented. The spring pin runs through the front of the trigger assembly and has, on each end, a half head, a half moon. The pin will rotate 180 degrees. I needed to lube it and work it but it moved. I believe this pin orientation was the cause of about 2 hours of frustration. More on this later.

    Took trigger out and didn't pay attention to anything (must be like a BAR, right? Wrong.)
    Right action bar (closest to me) immediately dislodged. Oh oh.
    Looked at the left action bar immediately and tried to get a look at its alignment, etc. It has a "button" on the end, the left one didn't so I had a fix on whether they were interchangeable. I would say no. Took it out as well.
    Removed receiver(#PO21155), it comes right out.

    I might add that my gun was absolutely filthy.

    Removed bolt. Filthy.

    Magazine was empty except for the carrier. Tried to work the carrier pin again but it wasn't going easily so I left it alone.

    Cleaned everything with solvent, Montana Xtreme Bore Shine, then wiped lightly with Break Free. If I had Kroil, I would have used that.

    Then I had to take the forearm off, naturally. Took barrel off, forearm slid right out. Inside tube was filthy as well as the outside of magazine tube.

    Cleaned everything with solvent and then with CLP. Used Qtips with solvent to really work the grooves and channels in the receiver, for lack of a better term.

    Re-assemble in reverse order.

    Now, the finicky part: the action bar/trigger install. This took me a long time but I was numb and dumb and wouldn't make the same mistake twice, so it's easy.

    Orient the trigger spring ends into the channel in the receiver while bracing the action bars. For me, and what eventually made the difference, I rotated the pin so that the rounded edge was hitting the lower edge of the groove, the flat side was high. Before, I had the flat side on the lower groove and tried unsuccessfully for way too long. The lower groove is actually the upper groove once you flip the gun. I also had to work a thin screwdriver to press open the action bars so that the trigger would seat between them. Another thing that was killing me was the positioning of the action bars. I knew the notches had to line up with the trigger pins but it's hard to see the alignment once you start to seat the trigger. That's why the pencil mark would have been helpful.

    Last night I didn't know any of the nomenclature but I have my manual next to me. All in all, it's simple, with the action bars being the most problematic.

    Good luck and post how it went.


  3. treetohouse

    treetohouse New Member

    Jan 25, 2009
    hey you saved me a lot of time i had the pin upside down as you did. i don't think there's anything wrong with your shotgun mine double loads or some times just drops the shell out on occasion also, don't know why maybe it was dirty or maybe it just happens. any way i was hunting in the rain a few days ago so when i got back i took my gun completely apart and dried it off then today i was cleaning it up and went to reassemble it and got stuck with the trigger mechanism but it worked fine when i turned the pin over like you said thanks. i also like this shotgun a lot the only thing i had to get use to was that it shot high now that I'm over that i love the gun.
    Last edited: Jan 25, 2009
  4. Marlin

    Marlin *TFF Admin Staff Chief Counselor*

    Mar 27, 2003
    At SouthernMoss' side forever!
  5. TRAP55

    TRAP55 Active Member

    May 10, 2004
    Occupied Territory Of Kalifornia
    Part numbers 10 and 11 are the shell stops, they stop the second round from feeding with the first.
    The first step that usually cures the problem is a good cleaning. Bits of powder residue, pieces of plastic from the shell crimp, etc. will lodge in behind them and cause problems.
    They can become bent or worn just enough to let that second round jump by too.
  6. tustijo

    tustijo New Member

    Jan 30, 2011
    Thanks to all. The tip about orienting the spring pin saved me that two hours you mentioned. I ended up driving out the carrier pin (probably didn't' have to do this, but made cleaning the gun internals a bit easier. When I pulled the trigger mechanism out, ended up with an extra part (roll pin) I could not locate a home for (Oh crap, now what?). Didn't realize what it was for until I saw the post with the exploded view link and found this was the keeper for the carrier pin. I had the gun put back together by this point, and it seemed to work fine, plus had cleaned up the mess on the kitchen table before the missus got home, so will disassemble later in the week to re-install (Probably good practice anyway).

    Great gun, but definitely easier to take apart than put together. Not as bad as a carburetor, but still plenty of fuel for frustration without these helpful posts.

    I'm embarrassed to admit that I'd never had the gun apart before, and like hlane commented, mine was also absolutely filthy and in dire need of a good cleaning and lubrication.
    Gotta love the internet! Thanks guys!
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