Thoughts about modifying mag tube for mag extension

The #1 community for Gun Owners of the Northeast

Member Benefits:

  • No ad networks!
  • Discuss all aspects of firearm ownership
  • Discuss anti-gun legislation
  • Buy, sell, and trade in the classified section
  • Chat with Local gun shops, ranges, trainers & other businesses
  • Discover free outdoor shooting areas
  • View up to date on firearm-related events
  • Share photos & video with other members
  • ...and so much more!
  • 71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    Someone I know :innocent0 grabbed a new, semi auto 12 gauge.

    There's videos of this same shotgun being modified for home defense use.

    Exact mag tube extension, pictured below.

    The mag tube, where the nut holds the forend on, is peined over on it's entire inner diameter, to hold the spacer and tube spring from flying out (at least that's my guess?)

    The video states to "cut off" 2 threads, which would eliminate the "pein" and then allow swapping the follower, the spring, and also allowing the extra shells to easily clear that (now gone) obstruction. I am a "mechanic", so that idea doesn't make a lot of sense to me.

    My (potential) method is going to be to use a carbide bit, and remove the peined over section, which would not lose any threads/length, of the existing tube, if that makes sense?

    Just wondering if there's any feedback/thoughts from anyone who has actually done this modification.

    And I am hopeful, that this thread doesn't somehow get turned into a cooking, or oil change thread, lol.

    p.s. The mag tube extension is getting installed no matter what. I'm not concerned about voided warranty.
     

    Attachments

    • magtube extension.jpg
      magtube extension.jpg
      28.7 KB · Views: 689

    Semper Noctem

    Desk Rabbit
    Aug 9, 2011
    4,029
    Fairfax, VA
    I've drilled out the peended detents on an 870 to install an extension, but never on the models listed in the screenshot. Either way, I wouldn't sweat it too much. Use a dremel to smooth out the hole on both sides, hit it with some cold blue or Brownells oxfo and shoot it. Pics or it didn't happen.
     

    71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    I've drilled out the peended detents on an 870 to install an extension, but never on the models listed in the screenshot. Either way, I wouldn't sweat it too much. Use a dremel to smooth out the hole on both sides, hit it with some cold blue or Brownells oxfo and shoot it. Pics or it didn't happen.

    Thanks for reply.
    I do hope to document the mini "build". The mag tube extension should be here today, and the adjustable stock, tomorrow.
     

    byf43

    SCSC Life/NRA Patron Life
    My youngest son bought a Citadel "Boss Hog" (conventional stock) 12 ga semi-auto.

    The procedure you're describing is exactly what has to be done, to install the Carlson's "Benelli Nova" magazine extension.

    IF he really wants the extension put on, I'll have to do it, with him helping.
    (He can turn a wrench, but, he's not confident enough to this job.)

    There's a couple of youtube videos that show the installation.

    Here's one:
    [YT]N6KcBuDRA-k[/YT]
     

    Bountied

    Ultimate Member
    Apr 6, 2012
    6,880
    Pasadena
    I've drilled out the peended detents on an 870 to install an extension, but never on the models listed in the screenshot. Either way, I wouldn't sweat it too much. Use a dremel to smooth out the hole on both sides, hit it with some cold blue or Brownells oxfo and shoot it. Pics or it didn't happen.

    Yeah I did this on an 1187. The tube just needs to be made flush and smooth on the inside to add the extension. If the Nova has a peened/rolled section to hold the spring in you need to open it up and smooth it out so the new spring wont bind. It should be fairly simple. I wouldn't cut any threads unless you have to. I had a Nordic +5 on my 1187 and got a Colfax tactical barrel clamp/sling mount. Worked really well, zero issues.
     

    71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    My youngest son bought a Citadel "Boss Hog" (conventional stock) 12 ga semi-auto.

    The procedure you're describing is exactly what has to be done, to install the Carlson's "Benelli Nova" magazine extension.

    IF he really wants the extension put on, I'll have to do it, with him helping.
    (He can turn a wrench, but, he's not confident enough to this job.)

    There's a couple of youtube videos that show the installation.

    Thanks. Yes, I saw that video, but the whole hose clamp, cutting off the end thing doesn't sit well with me for some reason.

    Yeah I did this on an 1187. The tube just needs to be made flush and smooth on the inside to add the extension. If the Nova has a peened/rolled section to hold the spring in you need to open it up and smooth it out so the new spring wont bind. It should be fairly simple. I wouldn't cut any threads unless you have to. I had a Nordic +5 on my 1187 and got a Colfax tactical barrel clamp/sling mount. Worked really well, zero issues.

    Thanks. Good to know there's no issues.
    And yes, this shotgun looks to be ROLLED OVER on the edge, as opposed to peined. I couldn't think of the right word when I typed the OP out this morning.

    Any suggestions on how to keep the spring slightly depressed while clearancing the mag tube? I'm going to look closer at it this afternoon, and may just remove that whole mag tube, if it's feasible. That also saves me from bringing a half shotgun into work and get quizzed by the nosey's...lol
     

    Bountied

    Ultimate Member
    Apr 6, 2012
    6,880
    Pasadena
    Thanks. Yes, I saw that video, but the whole hose clamp, cutting off the end thing doesn't sit well with me for some reason.



    Thanks. Good to know there's no issues.
    And yes, this shotgun looks to be ROLLED OVER on the edge, as opposed to peined. I couldn't think of the right word when I typed the OP out this morning.

    Any suggestions on how to keep the spring slightly depressed while clearancing the mag tube? I'm going to look closer at it this afternoon, and may just remove that whole mag tube, if it's feasible. That also saves me from bringing a half shotgun into work and get quizzed by the nosey's...lol

    It might be awkward but I'd use a dowel to push the spring down while you Dremel the opening until it can be removed. Other than that I'm not real familiar with the Nova series. I shoot an A5 mostly.
     

    byf43

    SCSC Life/NRA Patron Life
    Thanks. Yes, I saw that video, but the whole hose clamp, cutting off the end thing doesn't sit well with me for some reason.

    IF I wind up modifying my son's "Boss Hog", I'll be using the hose clamp method, so that I can cut the tube 'straight and square'.

    I suppose a metal cutting chop saw would be best, but, I don't own one of those, and don't have access to one.
     

    71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    IF I wind up modifying my son's "Boss Hog", I'll be using the hose clamp method, so that I can cut the tube 'straight and square'.

    I suppose a metal cutting chop saw would be best, but, I don't own one of those, and don't have access to one.

    I'm going to use the carbide bit method, and "ream" it out from the inside, then smooth with a sandpaper roll.

    The clamps are not square the whole way around, which may not be that big of a deal, but I highlighted the areas I am referring to. I'm just not comfortable with removing 2 or so threads to make it happen. I'll post up when I do mine, which hopefully is tonight.
     

    Attachments

    • bit1.jpg
      bit1.jpg
      21.8 KB · Views: 207
    • bit2.jpg
      bit2.jpg
      28 KB · Views: 216
    • clamp1.jpg
      clamp1.jpg
      23.1 KB · Views: 214
    • clamp2.jpg
      clamp2.jpg
      20.6 KB · Views: 209

    byf43

    SCSC Life/NRA Patron Life
    I'm going to use the carbide bit method, and "ream" it out from the inside, then smooth with a sandpaper roll.

    The clamps are not square the whole way around, which may not be that big of a deal, but I highlighted the areas I am referring to. I'm just not comfortable with removing 2 or so threads to make it happen. I'll post up when I do mine, which hopefully is tonight.

    Shweeeeeeeeeeeet!!!!!!!!!

    PLEASE let me know how it turns out.

    I got in Brad's safe this afternoon, and was looking over what needs to be done.

    Doesn't look too intimidating.
     

    71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    Shweeeeeeeeeeeet!!!!!!!!!

    PLEASE let me know how it turns out.

    I got in Brad's safe this afternoon, and was looking over what needs to be done.

    Doesn't look too intimidating.

    Well, the prep for the extension went well. Used a cordless Milwaukee drill so I didn't go too far, too deep.

    Unfortunately, and unknown as to why, I ordered the wrong extension, so have to reorder the correct one tomorrow.

    It turned out nice, and was not a lot of effort at all.

    On the bright side, my 1st attempt at cast iron skillet cooked steaks (from another thread here) turned out awesome! Lol
     

    Attachments

    • 20210308_152036.jpg
      20210308_152036.jpg
      73.9 KB · Views: 195
    • 20210308_154317.jpg
      20210308_154317.jpg
      93.1 KB · Views: 210
    • 20210308_154353.jpg
      20210308_154353.jpg
      40 KB · Views: 194
    • 20210308_165926.jpg
      20210308_165926.jpg
      94 KB · Views: 199
    • 20210308_174502.jpg
      20210308_174502.jpg
      96.6 KB · Views: 213

    byf43

    SCSC Life/NRA Patron Life
    Why was the extension, "wrong"????

    I was under the impression that the Carlson's Benelli Nova/SuperNova extension was correct.

    ??? :shrug: ???

    Which one are you ordering???

    BTW........... the steaks look GREAT!!!!!!!!
     

    71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    Why was the extension, "wrong"????

    I was under the impression that the Carlson's Benelli Nova/SuperNova extension was correct.

    ??? :shrug: ???

    Which one are you ordering???

    BTW........... the steaks look GREAT!!!!!!!!

    Thanks. They were pretty damn good.

    It was 100% my fault, ordering wrong. The Nova/SuperNova extension is right. I ordered the one for the other Benelli option. Cant recall the model off hand.
     

    71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    Please keep us informed on the progress and the end result.
    Very interested in this.

    I will. New, correct extension ordered this morning. Says it'll be here Friday. ATI stock should be here today.

    Only thing I can figure is I was flip-flopping around everywhere online looking to see who had what in stock, and simply clicked on the wrong option, lol.

    One thing I will say is, the 8 round extension (as Carlson calls it), would be sticking out 2 inches or so past the barrel. I ordered a 7 round version, which should be close to even with barrel.

    I'll take an attach a pic of the 8 rounder later when I get home, to show you how it looks. I didnt like it.
     

    byf43

    SCSC Life/NRA Patron Life
    I will. New, correct extension ordered this morning. Says it'll be here Friday. ATI stock should be here today.

    Only thing I can figure is I was flip-flopping around everywhere online looking to see who had what in stock, and simply clicked on the wrong option, lol.

    One thing I will say is, the 8 round extension (as Carlson calls it), would be sticking out 2 inches or so past the barrel. I ordered a 7 round version, which should be close to even with barrel.

    I'll take an attach a pic of the 8 rounder later when I get home, to show you how it looks. I didnt like it.

    Great!!!!!
    My son is on his way back from Ohio, and should be home later tonight.

    I look forward to seeing the picture, so he can see, also.
     

    71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    Great!!!!!
    My son is on his way back from Ohio, and should be home later tonight.

    I look forward to seeing the picture, so he can see, also.


    No problem. I'm wanting it to look more like my police 870's, (or the all black Maverick 88) as far as barrel/mag tube lengths.
     

    Attachments

    • shotties1.jpg
      shotties1.jpg
      68.1 KB · Views: 157

    71Chevelle427

    Ultimate Member
    MDS Supporter
    Jan 19, 2015
    3,298
    B'More County, Maryland
    Here is the 8 round extension, compared to the 20" barrel.

    3" difference, so the 7 round one should be perfect.

    I put the stock on, but want to wait until the extension is on first, before adding those pics.
     

    Attachments

    • 20210309_154122.jpg
      20210309_154122.jpg
      87.8 KB · Views: 156
    • 20210309_154104.jpg
      20210309_154104.jpg
      66.5 KB · Views: 169

    Users who are viewing this thread

    Latest posts

    Forum statistics

    Threads
    274,915
    Messages
    7,258,460
    Members
    33,348
    Latest member
    Eric_Hehl

    Latest threads

    Top Bottom