Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Cuss * Growl * Spit * Cuss


Robocop1051

Recommended Posts

I started assembling another "black rifle". This is a Mega Arms AR15 with a Rainier 14.5" mid barrel, DD 12.0 FSPM and AA mid length piston.

This piston and handguard combo do NOT like each other! Used my rotary tool to get the cuts started on the HG, then diamond files to finish off the cuts. Loooong pain-staking work to make four even notches in the bottom of the handguard.  I had to install and remove the HG about 7 or 8 times to get the fit right.

After about 4 hours of filing and fitting, I finally got the gap correct, all the parts installed, and all the bolts cranked down real tight....

That is about the time that I remember that I only put the barrel nut on hand tight.... CRAAP!!!! <nutkick>

I need a break.

Link to comment
Share on other sites

Robo, how you think I got a YHM Specter gas block under a DD Mk18 RIS II rail?!...  <dontknow>

Modding!!!  <lmao> <laughs>

Don't let anyone tell you "it doesn't fit..."  That poop fits. 

With "clearancing."  <thumbsup> ;D  I feel your pain.  Literally. 

DDMk18RISII1.jpg

Link to comment
Share on other sites

  • 4 weeks later...
  • 2 weeks later...

Just got a RRA lower 5.56 would like to add a lightweight upper w/15.5 barrel and free float railed handguard what are your thoughts.Shoot on bros.

After assembling mine, I would probably go another route if I had it to do over again... looking back I would have liked to have gone with a 14.5" mid-length pencil barrel w/ .625 low profile gas block. I do fancy the Daniel Defense lightweight rails, but an Superior Weapons System rail would look nice too. I am also proud of my Apex CNC "Gator Grip" handguard... FF handguards are always a hard point for me to make a decision.

Link to comment
Share on other sites

unforgiven, I've built a BUNCH of 14.5" carbine gas guns, and two 16" midlength gas guns.  I've been itching to build a 14.5" midlength gas for awhile - actually intended to build that config for the "Pink Range Loaner" that I still want to do.  <lmao>

Last 14.5 carbine gas I did was with a BCM lightweight profile barrel, for my kid - that's a damn fine shooting weapon, right there.  If the midlength gas barrel would have been in stock at the time, I probably would have done that instead of the carbine gas - alas, it wasn't in stock.  The barrel contour profile makes a big difference in swinging the gun, and carrying it for awhile - my kid won't be carrying for long durations, but he is skinny like a beanpole, and needs all the help he can get when he's driving that thing around on different targets.  <laughs>

Lightweight profile barrels - I love 'em.  ;D <thumbsup>

Link to comment
Share on other sites

Come to think of it. I would probably not free float a 14.5" LW middy. I think an A2 fsb with a Magpul MOE would be just fine for me. Very light and efficient.

Free floating is for getting that extra bit of accuracy out of your barrel. If I'm going with a 14.5" pencil barrel, I've obviously thrown out the idea of sub MOA. A mid length MOE handguard is light and can handle all the rails/accessories I could ever ask for.  The FSB can be upgraded with KNS or Trijicon sights. A rear BUIS or even a fixed Troy/DD would suffice for irons. Slap on an EOTech and I'm done. <thumbsup>

Link to comment
Share on other sites

gas-systems.jpg

There is also a "pistol" length for barrels under 10".

Carbine is good for 10"-16"

Mid is good for 14.5"-18"

Rifle is good for 18"+ (.308 can use a 16" barrel w/ rifle length gas)

There is also a barrel out there called a "Dissipator". I think Bushmaster originally made it. It has a carbine gasblock hole, as well as a rifle length faux-gasblock location. This is to have a low profile carbine gas system under the handguard. Then put an A2 front sight block at the rifle length position, so you can have your sights near the end of a 16" barrel. These barrels are rare, and usually handmade. I know someone here recently made one... Maybe he will step up and show off.

xstu5950b.jpg

I think BCM is playing with a lot of different length combo's (with a similar concept in mind) for various SBR's.

Link to comment
Share on other sites

What is the difference between carbine and mid length gas <dontknow>

I was gonna say "About 2 inches - which can be really important sometimes..."

Robo's explanation was much better...  <lmao>

Swing weight will always be subjective, but the more weight you have further forward, the more you'll feel it.  When you're considering mounting a lo-pro gas block 2" further forward, plus the additional weight of 2 more inches of gas tube, the impact is really pretty minimal.  Bottom line - you'd REALLY have to be used to one of those setups, then test back-to-back with the other, just to even be able to tell the difference.

Now, if you freefloat the thing, and you were running a heavy light on a rail, out at the end of a carbine rail - then you move that heavy light to the end of a midlength rail - you'd feel that initially.  Might affect initial training, but you'd get used to it pretty quickly.

Link to comment
Share on other sites

You know even my money is tight I was gonna try and support uncle Armalite and get the upper for $399.99 sent him an Email a few days ago asking about maybe different barrel [14.5] or twist left my #no. and mentioned being on this form no response at all.Then I called sales left #no. got a call later in the afternoon asked the guy same questions he said it was what it was.Then I mentioned I wanted to put it on a RRA lower and I could sense an attitude,and he mentioned guys that worked for Armalite broke off and started RRA.It was almost like the attitude I had found in some Harley shops [when things were good] that we don't really need you,you need us.Well it wasn't exactly what I wanted but was trying to support.Will follow the suggestions previously mentioned and put together exactly what I want/need FYI.Shoot on bros.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...