< Back to the Main Site

Author Topic: Help with ar  (Read 2143 times)

Offline btw.2008

  • Forum Member
  • *
  • Join Date: Jul 2013
  • Posts: 4
Help with ar
« on: October 21, 2013, 07:04:18 PM »
I am curious if anyone knows how the process of changing a handguard on a rock rivers arms lar-8 works. I know they use their own barrel nut and can only use a few different handguards that they sell. Changing it out doesn't seem to bad but the gas block is attached using dowel pens instead of screws.   Has any delt with something like this before?  Or know a direction to go?  I want to make sure that this could be changed before getting into a gun like this. Thank you

Offline bkoenig

  • Gun Show Volunteer
  • Powder Benefactor
  • *
  • Join Date: May 2009
  • Location: Lincoln, NE
  • Posts: 3677
  • Aspiring cranky old gun nut
Re: Help with ar
« Reply #1 on: October 21, 2013, 07:43:45 PM »
I'm not familiar with that setup.  Can you post pics? 


Offline gsd

  • 2013 NFOA Firearm Rights Champion award winner
  • NFOA Full Member
  • **
  • Join Date: Oct 2010
  • Location: Lincoln, NE
  • Posts: 1831
Re: Help with ar
« Reply #2 on: October 21, 2013, 11:08:38 PM »
Is it a Delta Nut style or threaded? the Gas block is no big deal usually, new pins are available. You drive the pins out and do your work, then drive the new ones in. If you have to swap out the barrel nut (which is a possibility) they aren't very expensive. You just need to make sure you have access to a vice and block to properly torque the nut down.

And like bkoenig said, pictures would help, RRA, offers a few different styles of the LAR-8.
It is highly likely the above post may offend you. I'm fine with that.

Offline btw.2008

  • Forum Member
  • *
  • Join Date: Jul 2013
  • Posts: 4
Re: Help with ar
« Reply #3 on: October 22, 2013, 04:23:35 AM »
I think it's the delta ring. The new quad rail does come with a new barrel nut. Here is a link to the set up. https://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=506   Difference is this gas block has fixed iron sites and where those 2 screws are it has dowel pins. Do they need replaced or can they be reused?  How do you know the gas block is centered over the hole in the barrel?  Thanks again

Offline FarmerRick

  • NFOA Co-Founder
  • *****
  • Join Date: Mar 2008
  • Location: Valley, NE
  • Posts: 3250
  • Antagonist of liberals, anti-hunters & hoplophobes
Re: Help with ar
« Reply #4 on: October 22, 2013, 06:23:17 AM »
I think it's the delta ring. The new quad rail does come with a new barrel nut. Here is a link to the set up. https://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=506   Difference is this gas block has fixed iron sites and where those 2 screws are it has dowel pins. Do they need replaced or can they be reused?  How do you know the gas block is centered over the hole in the barrel?  Thanks again

The pins can be reused, no problem.

If you are also reusing the gas block/front sight, it will only go on in one position due to the way the assembly is drilled for the pins during the initial assembly by Rock River.

99% of the time tapered pins will be used, and they will need to be driven out towards the ejection port side of the rifle, and reinstalled in the opposite direction.



They make a pretty nice fixture for holding the barrel while driving out the pins, but I just use a couple small blocks of wood of appropriate size.


Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety.

Offline btw.2008

  • Forum Member
  • *
  • Join Date: Jul 2013
  • Posts: 4
Re: Help with ar
« Reply #5 on: October 22, 2013, 07:56:17 AM »
I appreciate the response. Doesn't sound to horrible if they are tapered. My biggest worry was getting the hole in the gas block directly over the hole in the barrel.

Offline gsd

  • 2013 NFOA Firearm Rights Champion award winner
  • NFOA Full Member
  • **
  • Join Date: Oct 2010
  • Location: Lincoln, NE
  • Posts: 1831
Re: Help with ar
« Reply #6 on: October 22, 2013, 08:37:22 AM »
the bottom of the barrel is sometimes notched so it will center itself.
It is highly likely the above post may offend you. I'm fine with that.

Offline 00BUCK

  • Powder Benefactor
  • *
  • Join Date: Mar 2009
  • Location: Bellevue
  • Posts: 510
Re: Help with ar
« Reply #7 on: October 22, 2013, 12:01:24 PM »
I appreciate the response. Doesn't sound to horrible if they are tapered. My biggest worry was getting the hole in the gas block directly over the hole in the barrel.
Again there are several good you tube videos. Almost all gas blocks are made with a hole bigger than the gas port in the barrel. And they are meant to have a 1/16 gap from the back of the gas block to the gas block stop on the barrel. That is in case you put a regular style fore stock on your gun with the front cap. I usually just use a thick business card to set that gap.

Offline shovelhead69

  • NFOA Full Member
  • **
  • Join Date: Jan 2013
  • Posts: 85
Re: Help with ar
« Reply #8 on: November 01, 2013, 10:25:05 PM »
I have extra pins (if needed) and the correct tools to make this easy. If you are close to the Omaha area, I can show you how or you can watch and learn.









A coward blocks and hides when he is not man enough to confront in person.
To accuse a man for the sake of drama is a cowardly timid man's work (Rick)

Offline btw.2008

  • Forum Member
  • *
  • Join Date: Jul 2013
  • Posts: 4
Re: Help with ar
« Reply #9 on: November 05, 2013, 05:40:48 PM »
If you do have all te tools and the special barrel nut wrench for this I would be interested in learning how to do this. Thank you