Gas assembly fit too tight?

[Davy Crockett]

As per the title, is there such a thing?

I installed my new USGI gas assembly last night and it took some serious persuasion with a plastic block and a hammer to seat the thing. From what I read I thought it should only need to be tapped into place. The norc unit was very sloppy and basically fell off without being touched.

On the bright side my GLFS now indexes properly and tightens right up at 5 o'clock, no need for any shims on this unit.

 

[gnmontey]

Mine was really tight as well. Took some serious emery work to get it even close to going on. As it stands I still need to use a rubber mallet to get in on and off.

 

[Hungry]

I've had the same situation with my USGI gas system on my Douglas Hvy NM Stainless barrel. Had to whack it sternly with the wooden block and a plastic hammer. I expected that kind of firm fitting with a match barrel! Done this many times.

I'm glad that your timing for the gas cylinder lock was sweet at 5 o'clock and then firmly tapped into the 6 o'clock position. That's super!

Hey, all NM barrels have snug fitting tolerances. That's why they ARE NM reputation'ed. That's my experience anyways!



Barney

 

[giwolf]

The gas system fits these new Krieger medium weight barrels nice and tight too.

 

[Davy Crockett]

Good to know guys. Now to get her out and sighted in.

 

[Hungry]

At this point, I should provide some context to all this gas cylinder tension.

After owning half a dozen 12.x 'ed CA USGI M14's back in the 1980's, I discovered that the USGI gas systems SEVERELY needed lots of tightening up. Many of them could (read: battle rifle setup) play "Jingle Bells" with the noise and rattling they made.

So that began the quest for a unitized gas system. These fixes are well documented in the NRA publications from the late 1980's. It's old news. Many efforts were made to unitize the gas system and make everything a super tight fit. And that's what you get today.

Welding was popular by the USMC Armorers, drilling and tapping was favored by the US Army AMTU. Choose your poison.... Whatever works for you. The drilling and tapping method immediately froze the spindle valve in place. You M14 addicts who attended my clinics (31 of them now since 2002) know what happens when you don't understand what happens with the spindle valve.

Heeeeere kitty, kitty, kitty!



Barney