Help: Rust/Damage on exterior of AR Barrel?

[mikethebike]

I build all of my rifles and painstakingly ensure the fit is bang on, however this high quality ARP .750 barrel and a questionable DPMS block started to leak after only a 1000 rounds.

why would you put a dpms part on something like that, why not a bcm or a noveske gas block? Your quality of your rifle is dependant on the lowest quality of any of its parts

my noveske barrels have noveske gas blocks and noveske gas tubes

 

[RobertMcC]

Aside from this post, ive never ever seen a gas block come off on its own through normal wear and tear. But I dont jump from helicopters and run around in the sand, so...

Do they really come off on their own?
If so isnt that a major design flaw?
Must be a reason why KAC puts that shiat in it!

Too bad KevinB wasn't around there to answer why they use the glue. I only seen one come off, It used 3 set screws. The rifle was still running delta ring and hand guard so the counter spring pressure and vibration was pushing the gas block forward. Thus cutting off the gas.

But asking around weapons techs other AR builder if they gooped up or used anything to seal gas blocks and the answers were all huh, no, WHY?

The clamp on gas block that was on my gun fighter AR never loosened up and TV press pass abused it.

why would you put a dpms part on something like that, why not a bcm or a noveske gas block? Your quality of your rifle is dependant on the lowest quality of any of its parts

my noveske barrels have noveske gas blocks and noveske gas tubes

Last AR15 I built and I swore I wouldnt build another ( actually was a rebarreling job for a friend ) It was a un known upper, DPMS barrel, NEA Gen 2 rail and barrel nut. The barrel nut had to be shimmed to index proper and I had to order shims ( that was a first )

His old FSB the pins didnt line up with the new barrel so couldnt use that one to chop. He didnt want to chop the new one. He wanted a low pro block. One came drilled too short and gas tube pin wouldnt line up so I had to go with another company.

Probably why I stuck with Eagle Arms, Armalite and or Colt.

 

[-[Crosshair]-]

I've seen Armalite AR-10T (in the CF) gas blocks come loose and slide forward, pulling the gas tubes with them and creating cycling issues, after prolonged firing. The two set screws just wouldn't stay in place, even with blue Loctite. Drilling two dimples under the barrel for the set screws to seat in and the blue Loctite fixed this.

 

[Trinimon]

You'd figure they'd use something that holds up to higher temps like Rocksett which goes up to 1100ºC. Blue loctite breaks down at 250ºC.

 

[Sqr]

why would you put a dpms part on something like that, why not a bcm or a noveske gas block? Your quality of your rifle is dependant on the lowest quality of any of its parts

my noveske barrels have noveske gas blocks and noveske gas tubes

Agreed I did chinse out with this gas block feeling that DPMS had quality products. My latest Jury Barrel build has a clamp on JP gas block.

 

[RobertMcC]

Agreed I did chinse out with this gas block feeling that DPMS had quality products. My latest Jury Barrel build has a clamp on JP gas block.

DPMS were decent. But they never been any more then a low to mid range AR15.

I've seen Armalite AR-10T (in the CF) gas blocks come loose and slide forward, pulling the gas tubes with them and creating cycling issues, after prolonged firing. The two set screws just wouldn't stay in place, even with blue Loctite. Drilling two dimples under the barrel for the set screws to seat in and the blue Loctite fixed this.

That what happened to the gas block on my fathers AR. Had to dimple the barrel. Because he didnt want to switch over the a FF tube.

 

[Sqr]

DPMS were decent. But they never been any more then a low to mid range AR15.



That what happened to the gas block on my fathers AR. Had to dimple the barrel. Because he didnt want to switch over the a FF tube.

As stated in another thread about supporting local gun stores, Its difficult to get what you truly want and usually I make do. Now I purchase most parts from Brownells.