Current best deal on BCG?

[markm]

Word on the street is they are actually LaRue!

As long as it's not LWRCi. It would have never functioned if that were the case.

[georgeib]

FWIW, I received a reply from AR15Discounts today with an RMA and label for the BCG. They're offering me store credit or a replacement. Think I'm going to take them up on it rather than dicking around trying to diagnose this thing, even though my general proclivity is to try and solve things and understand why they happened. Must be getting old.

[markm]

Well that's good.

[prepare]

FWIW, I received a reply from AR15Discounts today with an RMA and label for the BCG. They're offering me store credit or a replacement. Think I'm going to take them up on it rather than dicking around trying to diagnose this thing, even though my general proclivity is to try and solve things and understand why they happened. Must be getting old.

Thank them for the replacement and tell them you would also like to know what is wrong with the first BCG and would appreciate it if they could follow up with you on the problem.

[markm]

Thank them for the replacement and tell them you would also like to know what is wrong with the first BCG and would appreciate it if they could follow up with you on the problem.

As a retailer, I doubt that have the tools, time or knowledge to figure it out. Something like this (assuming it's an issue beyond lack of lube) is going to be a few thousandths +/- somewhere.

The instruments BCM showed for checking their BCG specs and dimensions is pretty sophisticated. There's no way a retailer is going to have anything in that arena.

[georgeib]

The BCG doesn't really get THAT hot though. I suppose the rings might on aggressive firing volume.

I always used to chuckle when the piston gun peddlers would act like holding the bolt after a mag dump was miraculous... even though you can do that with a DI gas system too.

This got me to thinking that it was the one piece ring I had laying around that I had installed in there and forgotten... Yeah, I know. If that ring gets really hot, seems it would expand in a way that may make it bind, as opposed to standard rings that can expand into the gaps... So, I switched back to the 3 rings and I'm going to give it another shot. May have found the issue here.

[markm]

So, I switched back to the 3 rings and I'm going to give it another shot. May have found the issue here.

I think so.

[DG23]

This got me to thinking that it was the one piece ring I had laying around that I had installed in there and forgotten... Yeah, I know. If that ring gets really hot, seems it would expand in a way that may make it bind, as opposed to standard rings that can expand into the gaps... So, I switched back to the 3 rings and I'm going to give it another shot. May have found the issue here.

Not saying those McFarland rings are good or bad -

But,

They have been out a long time and have not personally read any stories about them seizing up when they got heated...

I would swap back to the originals for testing purposes here but would not throw the McFarland stuff in the trash just yet. May not be their fault.

[georgeib]

Not saying those McFarland rings are good or bad -

But,

They have been out a long time and have not personally read any stories about them seizing up when they got heated...

I would swap back to the originals for testing purposes here but would not throw the McFarland stuff in the trash just yet. May not be their fault.

Agreed. I've had a McFarland in a BCM and have heated up a lot more. But perhaps combined with a tight carrier bore, it was too much. I'll find out on Tuesday. The RMA is good for 30 days.

[georgeib]

Well, as I suspected, it looks like the McFarland gas ring was the likely culprit, at least in conjunction with the tight bore of the AOP carrier. Today, with the standard gas rings, and a fairly generous amount of fresh lube, the rifle functioned flawlessly through a few mags at a FA ROF. Never got sluggish like it did last time, nor was the bolt sticking in the carrier afterwards.

I suppose an argument could be made for the BCG being better lubed, but that wouldn't explain why the bolt stopped sticking after it had cooled off (when I had the issue last week), unless I'm missing something.