Daniels Defense Upper Question

Got my new Daniels midlength upper. Took the bolt apart to check things out. I noticed they put a heavy extractor spring with the black bumper and a O ring on their extractor.
Is it ok to run it without the o ring? I usually run the heavy spring and black bumper on my other builds.

From what I understand, the o-ring helps if you’re having extraction problems - if you’re not, I wouldn’t worry about it.

Exactly.

Run it without, if you run into problems throw it back in.

Yep, what those guys said^^^.

From a previous thread on the matter.

https://www.m4carbine.net/showthread.php?t=98347

one of the “name” trainers, LAV or Pat Somethingorother, mentioned how they have seen extraction issues with DD in their class. I know no other details but they did say that adding the o-ring cured the ills.

though I’ve not had any issues personally, I have added the o-ring preventively to all my DD extractors and have not had any negative effects…

I just picked up my first DDM4 and was also wondering the same thing. I usually run BCM BCGs and have never used the o-ring. I haven’t made it to the range yet with the DD, will probably try without the o-ring and see if it needs it. But am curious about others’ experiences with their DDM4s. I guess whether it needs the o-ring depends on how strong an extractor spring they use.

Also, for those that recently picked up DD rifles/uppers, are your bolts un-marked? Mine doesn’t have the typical “HP” “MP” markings on the bolt. I’m not concerned, I’m sure it was tested, but was surprised the bolt wasn’t marked.

It’s my understanding, and I could be wrong, that Paul (BCM) doesn’t typically recommend using the o-ring in his BCGs. When you get a BCM BCG the o-ring comes un-installed and I believe he only recommends using it if you have extraction problems or are running an SBR.

Totally normal for the unmarked bolt with DD

Thanks! Like I said, I wasn’t worried about it since I bought it from a reputable vendor (Rainier), but was just surprised that it wasn’t marked.