PA10 bolt question

[Mgderf]

I just built a brand new PA10, using most all PSA parts, including a brand new PA10 BCG.
I fired it for the first time this morning, and had issues with ejecting right off the bat, so I quit firing after only 4 rounds.

My issue was/is with the extractor I believe.
The extractor would not release the case. It would hold fast to the case whether the bolt held open or tried to return to battery.
'I literally had to pry the cases out from under the lip of the extractor.

Disassembled the BCG and removed the extractor arm.
Underneath, I found the normal spring, but wrapped around the spring was 2 very small o-rings. The o-rings only left 1 coil of the spring exposed, thus shortening the spring travel.

I removed the o-rings and re-assembled the extractor and BCG.
Things seem to cycle better now, by hand at least.

Question. Has anyone seen o-rings around an extractor spring?
What would their purpose be?
Could this have been a prank by someone at the factory?

I've dealt with my share of AR's, both 15's and 10's, but this was the first time I've found o-rings around an extractor spring.

 

[Mgderf]

Just back from the range.
No luck. Cases still won't eject.

Guess I let the dealer send it back to PSA.

 

[SSE]

The o-ring is correct. or 1 is anyway,
It sounds like you have a problem with the ejector not the extractor.
Is the spring loaded ejector working?

 

[Mgderf]

The o-ring is correct. or 1 is anyway,
It sounds like you have a problem with the ejector not the extractor.
Is the spring loaded ejector working?

Yes, the ejector is working well. There is a lot of tension on that side of the case.
Why would they put ANY o-rings around the spring?
What purpose does it serve?

 

[CountryBoy19]

Yes, the ejector is working well. There is a lot of tension on that side of the case.
Why would they put ANY o-rings around the spring?
What purpose does it serve?

The use of O-rings on AR-15 extractors is not a new or novel idea. Google it and you will get more results than you care to read. There is a lot of debate as to whether they actually help or not but I haven't seen much of anything that says they hurt. The general idea is that it changes the single extractor spring to a "compound" spring rate, and the rubber acts as more of a buffer material.