Author Topic: Rookie mistake  (Read 336 times)

Offline Drvred

  • Newbie
  • *
  • Posts: 16
    • View Profile
Rookie mistake
« on: January 05, 2019, 06:26:26 PM »
When I added the rail section on the front of my M-Lok handguard I placed I where the bolt touched the barrel where it swells back to full size.
I found that tonight after returning from the range, I corrected it after smacking myself in the forehead. It had hit enough to leave a mark on the barrel.
 My question is, what kind of silly effects would it have on accuracy?


Offline binazone

  • Jr. Member
  • **
  • Posts: 41
    • View Profile
Re: Rookie mistake
« Reply #1 on: January 07, 2019, 07:00:51 AM »
Plenty, no doubt. I noticed that conflict with mine and have to move the rail back a section . In addition, I would suggest making sure that the gas block is not anywhere near the handguard. Mine was actually so close, that I had to cut away the surrounding section of the handguard just to make sure it could never hit it.

Offline Drvred

  • Newbie
  • *
  • Posts: 16
    • View Profile
Re: Rookie mistake
« Reply #2 on: January 07, 2019, 11:24:18 AM »
Yeah, it's close all around, about 1/16- 3/32.
I can flex the bbl without hearing it hit. What I thought was the GB hitting the guard, was the bbl hitting the screw.

Offline CCW

  • Newbie
  • *
  • Posts: 14
    • View Profile
Re: Rookie mistake
« Reply #3 on: January 19, 2019, 08:28:56 PM »
Take a dremel cut off disk and cut off about 3/32 of the screw shanks from the MLOK so the screw tips are just flush with the MLOK nuts.   Locate the sling/bipod MLOK away from the gas plug bottom.

"Free floating" means nothing touches the barrel from barrel extension / upper retainer nut forward, except the gas block and gas tube, of course.   This "no touch" should be static from hammer drop to max. firing dynamic whip.

--CCW
« Last Edit: February 08, 2019, 02:39:34 PM by CCW »

Offline Foil

  • Jr. Member
  • **
  • Posts: 20
    • View Profile
Re: Rookie mistake
« Reply #4 on: January 20, 2019, 04:55:18 PM »
I did the very same thing with mine, actually.  I tested all my loads and eventually settled on one that was giving me 1/2 minute groups consistently......

Found my error later, and since I have a Proof barrel, it had made quite a mark in the carbon fiber.  Proof says I have nothing to worry about with delamination and that it's purely a superficial mark, so I'm not worried about that.

So now I'm very interested to see what on earth this was doing to my groups.  I had my grip mounted very far back, so it was pressing on the widest part of the barrel - I suspect in that position it doesn't have enough leverage to really do very much.  It didn't seem to do much to my groups, though I now have to re-test everything. 

But I made a MUCH worse mistake than you, due to my disorganized reloading bench and some products which shared extremely similar boxes.  I'm making a thread about that.  Live and learn!

Offline Drvred

  • Newbie
  • *
  • Posts: 16
    • View Profile
Re: Rookie mistake
« Reply #5 on: January 20, 2019, 07:15:13 PM »
Rifle shot better the last time I shot it, but looking more closely today, the gas block is WAY too close to the handguard. I think touching, or thousands off on 1 upper side, about 1/32 off the other and maybe 3/32 off the bottom. I think I need to buy a grinding stone, and have at it.

Offline binazone

  • Jr. Member
  • **
  • Posts: 41
    • View Profile
Re: Rookie mistake
« Reply #6 on: January 21, 2019, 05:07:35 PM »
Drv, after I got my PSA 20" upper, I noticed that the gas block was within 1/32" on both sides and the top. I took the forearm off and noticed the Parkerizing on the gas block was indeed scuffed. I cut off every piece of offending forearm with a Dremel, filed down smooth and repainted and now the barrel is really free floating. I also noticed that the Mlok base for my bipod was way too close so I cut those screws down as well. I suspect that a lot of folks are having some accuracy issues with barrels that aren't, in fact, "free floating".