Need a Specific Metric Screw - Source?

Discussion in 'Gun Project Questions & Gunsmithing' started by Phil3, Dec 10, 2018.

  1. Phil3

    Phil3

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    I have a Howa 223 barreled action that was bedded into a stock. I then added the Howa DBM kit. This fit, but the mag will not latch. The mags hits something, but I cannot tell what. So, I tried shimming the bottom metal away from the stock with two thin washers. That works, but, the rear action screw (tang) is too short now. It barely engaged before, and really needs to be longer. I need a longer metric screw, but cannot find one. Any good sources?

    Screw is black oxide, 6mm diameter, 36mm long from under screw head to end, threaded about 40% of its length, using a T-30 star driver (Torx) on a rounded head. The current 36mm length grabs one thread, barely. The tang is thick and can easily handle a 40mm length.

    Can't believe a screw is keeping me from using this mag system. The only other thing to do is start grinding away at the mag, but then the bolt may get caught up. I'd rather not try to alter the mag. I have two, and neither will latch.

    Phil
     
  2. John Valencic

    John Valencic

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    Contact the manufacturer of the bottom metal and ask them for suggestions. Could be your particular model needs the bottom metal modified. This would be the best thing to do before you start jury rigging it.
     
  3. Ggmac

    Ggmac Gold $$ Contributor

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    Could you cut the bottom of the torx head , thereby length ing the shaft ?
     
  4. quail farmer

    quail farmer Gold $$ Contributor

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    those screws are 6x1 you can get those at fastinal in allenhead.
     
  5. Dusty Stevens

    Dusty Stevens COVFEFE- Thread Derail Crew

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    Can you just shim the front maybe?
     
  6. Shawnba67

    Shawnba67 Silver $$ Contributor

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    6mmx1.00 is a super common thread. Should be able to score on at about anywhere. If its not x1. I have bought super long 1/4 bolts with the long unthreaded section and cut off to length and just use a die to make 6mm.
    6mm=.236 1/4=.250
     
  7. Bully

    Bully Silver $$ Contributor

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    Can you trim the latch? It’s a pretty common fix with DBM that I’ve seen unless yours is more complex than an M5 type that I’m thinking of.
     
  8. shoot4fun

    shoot4fun Gold $$ Contributor

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    McMaster-Carr would be my go-to place.
     
    B Nettesheim and spclark like this.
  9. spclark

    spclark Gold $$ Contributor

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    McMasterCarr.com

    upload_2018-12-11_11-30-48.jpeg
     

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  10. Phil3

    Phil3

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    I am the OP. Thanks for the helpful replies.

    In response to some suggestions.

    - I cannot cut the bottom of the existing screw enough to effectively lengthen the screw, as I need more length than such a fix would allow.
    - I tried shimming just the front, but does not help enough. The mag well is pretty much between both screws, and while the latch is at the front of the mag, shimming just the front does not seem to help as much as I thought it would.
    - If I have to make, using a 1/4 long bolt, I can do. I have a lathe and can get a die to do it.
    - The way the latch is designed, a spring loaded lever end snaps into a detent on the outside of the mag. I would need to lengthen the lever, or lengthen the detent on each mag.
    - McMaster Carr does have what I need in a 10 pack, but it an Allen screw vs Torx, but it will work. Thanks for that suggestion.
    - I did not see the Allen head version of the screw at Fastenal, but will look again. There is a Fastenall store nearby and can pick up any order there with no shipping. I will check again.

    With all these suggestions, I am confident I will get it working. Thanks to you all. Some other info.


    The rifle is a 223 Howa epoxy bedded into a Bell & Carlson stock. I replaced the stock Howa metal hinged floorplate assembly with Howa’s polymer detachable box magazine (DBM) option. The DBM fit fine, held in by two action screws (one into the bottom of the integral recoil lug, the other into the thick rear tang). So far, so good, but the mag will not latch. Close, but not quite. If the action screws are loosened a turn or two, and the DBM pulled out from the stock a bit, the mag latches fine. The problem is that the bottom metal w/latch is effectively too high in the stock, causing the mag to stop against the action before the latch can engage. There are options to fix, but feel the best way is to lower the bottom metal a bit, so the mag can go higher, and latch just as it hits the bottom of the action. Less than 0.100” should do it.

    Putting a washer under each screw and holding the DBM, action, and stock together (by hand and front action screw) and then inserting a mag allows the mag to latch. Because of the washer and already very short thread engagement of the rear tang screw, that screw (36mm in length) will no longer adequately engage the tang threads. Hence the need for a 6mm x 1.0, black oxide, Torx T-30, partially threaded, 40mm long round head cap screw. If longer, I can cut to length. I can use an Allen head if necessary.

    I have seen a couple of others do this exact same conversion on the same stock with the same action and DBM, and no problem. Perhaps due to unfavorable stack-up of tolerances, a minute amount of bedding compound on the rear tang, or…? No question, at least in the B&C stock, that rear screw is barely long enough to grab any threads and/or the stock marginally too tall for where the screw goes.

    Thanks,

    Phil
     
  11. hogpatrol

    hogpatrol Gold $$ Contributor

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  12. Bob L.

    Bob L. Gold $$ Contributor

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    Bolt Depot has what you want in 40 mm and longer. 40mm is prod. 18962. They sell single items, as well. I have used them often.
     
  13. Leaddipper

    Leaddipper

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    I’ve found MSC manufacturers supply Corp to have quite a variety of unique fasteners
     
  14. Robert

    Robert Silver $$ Contributor

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    DIN 912 socket head sapscrews usually available are 8.8 material quality, while Torx's are of better 10.9 or even more often 12.9.

    I would rather keep the OEM screws and trim the latcghlever ar already suggested.

    R.G.C
     
  15. Bob L.

    Bob L. Gold $$ Contributor

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    I forgot about the Torx head.
     
  16. Robert

    Robert Silver $$ Contributor

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    orx heads ISO 14580 are usually harder. Also, DIN 912 Socket heads have a head height = diameter.

    Tprx heads are 3/4 diameter hgh.

    To replace a Torx standard screw; DIN 7884 Low head Allen in order to not have the head protruding out of the countersink.

    R.G.C
     

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