MP5KSD Build from a newbie.
Page 1 of 2 1 2 LastLast
Results 1 to 10 of 19

Thread: MP5KSD Build from a newbie.

  1. #1
    Junior Member

    Join Date : Jan 2018
    Posts : 21
    Mentioned
    0 Post(s)

    Default MP5KSD Build from a newbie. [Completed w/video]

    I'll fill this in more when I get to a computer but the gist of it is K gun with an SD shroud, and a K barrel starting from a flat. Based on laying things out I should be able to keep it under 20" folded with ~8 in of 1.56 diameter suppressor.

    I ordered a bunch of parts from hkparts.net Robert rtg and some for sale threads on hkpro.com

    Blank space for pictures


    US made SD shroud from Robert RTG




    US made receiver flat and weld parts (rear sight base, case deflector,semi shelf, scope base, bushings for pins, reinforcement plates) from hkparts.net



    Parts as received from hkpro seller

    SP89 barrel w/sight tower
    Cocking tube/trunion attached to front cut of receiver
    Cocking tube support
    Cocking handle
    SEF lower pinned and welded
    Paddle mag assembly attached to cut receiver




    Parts after removing the required bits from the old receiver
    I used 1/4in end mill and just milled out the spot welds down to the thickness of the receiver. Screwdriver/hammer got everything apart


    Barrel threaded last night with 1/2-28 threads where the knurling for the sight tower used to be.


    Rough intended layout with my existing suppressor. If the folded stock adds 1.5in to the rear then I can fit just about 8in of suppressor and be right at 20in


    Top suppressor is a form 1 9mm 1.375"x8", bottom is also a form 1 but in 308 and is ~7" long x 1.5"

    Only thing I'm unsure of thus far is the cocking tube support doesn't latch forward in the cocking tube. The "ring" where it is supposed to detent exists but is either oversized or the pin is too short. Next sunday will be the folding of the flat. In the mean time, the cocking tube and support need milled down to SD specs, an adapter needs made for the front of the cocking tube so the sight tower has somewhere to sit (standard cocking tube not SD).

    ETA videos
    These are plated Herco rounds I shoot normally. A few transonic ones in there.
    https://youtu.be/us2CWsArYRY

    The N320 loads I made this morning need a bit more ass until it's broken in. Good Lord are they quiet though.

    https://youtu.be/033PqsRW7XY
    Last edited by Propeine; 03-26-2018 at 01:35 PM.

  2. #2
    AGG
    AGG is offline
    Unrepentant HKHolic
    AGG's Avatar
    Join Date : Feb 2007
    Location : Alabama
    Posts : 34,281
    Mentioned
    269 Post(s)

    Default

    Interesting--- keep us updated on your progress!!!

    Tony

  3. #3
    Junior Member

    Join Date : Jan 2018
    Posts : 21
    Mentioned
    0 Post(s)

    Default

    Today we tried rolling some flats...it isn't as easy as YouTube and the interwebs would have you believe. Mine is way too tight on the carrier. The LSC flat is most definitely worth the 50 % premium as well. The LSC flat has a concave starting surface for the cocking tube area that helps it roll up without peaking. Mine didn't have that and is a bit egg shaped.

    Probably going to have to make a mandrel. The 375 dollars is a bit excessive.

    Tonight I made up a .800 bar (per the HK receiver section views) and slid it into the cocking tube area. I also layed the mill head over to 32.5 degrees and with a .500 end mill made an ellipse approximating a 15/16 diameter but only .080 deep or so. I then proceeded to smash the egg at the top down to a round profile using my newly made tools. Before, my trunion seemed to me larger than the receiver would swallow. Now the bottom closes up nicely and is just snug around the trunion. The material moved around enough that there is more space everywhere. I'm pretty sure it's all salvageable although it will take some file work/sanding to smooth out the top to be aesthetically pleasing.








    Got some welding done tonight. Need steel and a carrier for forming it all up tight now. Carrier is more money than I care to spend just yet but Nate is going to let me borrow a PTR91 carrier for fit checking.
    Last edited by Propeine; 03-21-2018 at 06:45 PM.

  4. Remove Advertisements
    HKPro.com
    Advertisements
     

  5. #4
    AGG
    AGG is offline
    Unrepentant HKHolic
    AGG's Avatar
    Join Date : Feb 2007
    Location : Alabama
    Posts : 34,281
    Mentioned
    269 Post(s)

    Default

    Progressing nicely--- keep us updated!!!

    Tony

  6. #5
    Senior Member
    gt40doc's Avatar
    Join Date : Jan 2018
    Location : Arizona
    Posts : 189
    Mentioned
    0 Post(s)

    Default

    Your skills are most impressive!! I do wish that I had similar skills, but they are lacking in me. I do enjoy watching your progress, and learning from it.....thanx.

  7. #6
    Member

    Join Date : Jun 2017
    Posts : 51
    Mentioned
    0 Post(s)

    Default

    Welds look great, mind if I ask what tig welder you use?

  8. #7
    Junior Member

    Join Date : Jan 2018
    Posts : 21
    Mentioned
    0 Post(s)

    Default

    Just a Lincoln Precision 225. Straight Argon for gas. Very fine point on the Tungsten. I don't remember all the settings but can check next time I go to the weld shop.

  9. #8
    Junior Member

    Join Date : Jan 2018
    Posts : 21
    Mentioned
    0 Post(s)

    Default

    Well, my buddy and I decided maybe a mandrel is useful for all kinds of things. So 30 dollars in steel and some time yields this. Sure beats 379 dollars! Now everything will be forced to be square end to end, as well as allow for better rounding at the top of the cocking tube.




  10. #9
    AGG
    AGG is offline
    Unrepentant HKHolic
    AGG's Avatar
    Join Date : Feb 2007
    Location : Alabama
    Posts : 34,281
    Mentioned
    269 Post(s)

    Default

    Looking nice!!!

    Tony

  11. #10
    Junior Member

    Join Date : Jan 2018
    Posts : 21
    Mentioned
    0 Post(s)

    Default

    Pic dump

    The tactical Pacman rear sight alignment tool


    Recoil rod bushing assembly that had to be deconstructed and shortened


    HDPE SD shroud alignment tool


    Gumbanded together til Thursday. With some good luck I should be shooting by Saturday
    Last edited by Propeine; 03-21-2018 at 07:00 PM.

Page 1 of 2 1 2 LastLast

Sponsored Links

 
 

Posting Permissions

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

Search tags for this page

mp5k sd shroud welding

Click on a term to search for related topics.