What's an enhanced bolt?  I just got a Bushy Patrolmans M4 upper, does it have an EB?

The so called enhanced bolt is simply the regular Rock River Arms bolt carrier.  It has few slight changes that most people won't recognise or care about.  If you're building a rifle from scratch, the RRA enhanced carrier is very good quality and is ironically the least expensive option for a non-used carrier assembly, but there's nothing wrong with the 'normal' bolt carriers that Colt, Bushmaster, Armalite, et.al. have been using in their firearms for many times longer than RRA has been in the AR business.

The 'enhanced' carrier is an RRA product so the odds of finding one in your NIB Bushmaster are somewhere between slim and none.

RRA sell an enhanced carrier, LMT sells an enhanced bolt. Two different things. I dont know the whole story, you should ask Wes Grant ([email protected]) to tell you. he sells them, and knows the whole story.

There are 2 companies that I know of that do this:

Rock River and Olympic Arms

Oly ha been doing it since 2002, at least...

Basically, you take a M16 bolt and cut a single mill-cut where the sear would engage.

The result is a heavier bolt, as not as much material is removed from the rear of the boltcarrier, and no material is removed from the area around the firing pin.

Thanks

I am not sure what the exact details are that make a BC enhanced, however I bought a BM B/BC several months ago and it has the shrouded area over the firing pin.   When comparing it with my old (pre-ban) BC it is significantly differant in that it has (old one) less matierial on the round end and about 1/3 of the firing pin is exposed.  I have a BOHICA lower pre-ban and it isn't exactly MIL-SPEC.  The hammer is about 1/16 of an inch too high and the hammer drags on the older style BC.  But with the new BM "enhanced???" BC it shoots fine.  

My Bushmaster H-bar had an "enhanced" style bolt, straight from the factory.