Tell me about loose gas rings.

AR/M4 AR General Discussion
1

I have a new Bcg…i got it in november:)
The gas rings are really loose…spinning around up and down any way you want to move them very very loose…It appears to function ok, but it sometimes doesnt lock the bolt back on tula ammo with the last round…I know its tula and its on a 14.5 middy with a heavy buffer and it mostly locks back, but i cant help but wonder if the gas rings are keeping it from locking back with the tula everytime.

2

Whether or not the rings spin on the bolt isn’t telling you anything…they are supposed to do that whether they are new or not. Notice the gaps? Those close together when it fits in the carrier, and spread(hence the looseness) when the bolt is removed.

Clean and assemble your BCG. Fully extend the bolt from the carrier(as though it was unlocked.) Set the BCG down on a table balancing it on the bolt face. Does it collapse? If yes, then you need new rings.

I suppose you could hold it by the lugs and see if it extends from the collapsed position as well.

I wouldn’t make any assumptions regarding the functionality of any of my rifles based on crap Tula ammo.

3

I was shooting some reload today, just testing it out since it was some new shit I just loaded…started using the tula ammo I purchased surplus a while back and the exact same thing happened…its shit ammo, so shit happens. No big deal.

4

Please provide the other pertinent details.

  1. Make of the BCG.

  2. Barrel manufacturer.

These two items are rather important and I am 99% your gas rings have noting to do with it.

5

Its a good brand bcg and barrel

6

Good brand means nothing and is subjective. Do you want some assistance or do you want to play 20 questions?

7

It is a BCM bcg and a BCM 14.5 middy light weight complete upper.

8

^This. And gas rings are supposed to be somewhat loose. They get compressed when the bolt is inserted into the BCG. As long as they create a good seal, they are not the issue.

I have also noticed that Tula and Wolf ammo seem to have issues when used in my Mid-Length carbine until I replaced the gas tube. FWIW.

9

Let me ask a couple more questions why im at it…

My buffer tube was barely catching the retaining pin and i had to file a very small amount off it to make another turn…would that affect it?

Also I installed a centurion c4 rail and i tried and tried to tear the handguard cap off, but it tore all the way around the fsb until there was nothing left to grab ahold of…i ended up having to knock the pins out of the fsb and cut the remainder off…i reinstalled the fsb and it is apparently reinstalled back like it was becuase i didnt have to adjust the irons any, but i cant help but wonder about that also?

10

Ok, now that we have that out of the way. markm and I tested a BCM 14.5" middy a few years back when they were starting to be popular. We were able to run it with a wide variety of ammo and buffers. All the standard stuff- M193, M855, PMC Bronze and the like ran fine.

But, the Tula and Wolf crap is generally not the best choice. If you insist on running it you will probably need a carbine buffer.

11

If you filed on the tube, you either have something out of spec, or you simply didn’t know what you were doing.

Did you bother to read the installation instructions on Centurion Arms website to install the rail?

I highly doubt that the removal of the FSB is a problem. Run it with real ammo and I am 99% certain it will be just fine. Make sure you lube it properly also.

12

I had to file some off the tube…it barely had just a sliver of the pin and it wouldnt make another turn with out hitting it…Im sure something is out of spec…thats why i asked about it

It locks back on pmc bronze and it locks back on cbc m193…and it mostly locks back on tula, but the only reason i am asking about the tula …is ammo isnt exactly easy to find right now and my LGS has a ton of tula for 6.99

Followed the rail instrucions to the letter…the hand guard cap just tore around the fsb and not all the way down in it…im not the first person that has happened too

13

You could have left it, the cap doesn’t need to be removed all the way. If a little piece remains it doesn’t really matter to the weapon.

14

If you want to shoot Tula then you probably need to switch to a carbine buffer.