Doesn’t work
Replaced my old AR-10 bolt with a new one. I purchased the BCG from Brownells and upon receiving it, I immediately installed it. Its fit and finish were very nice and I was excited about using it. I took it to the range the very next day, locked and loaded a 20 round magazine. It fired the first round but would not extract the spent round. I had to use a small screwdriver to remove the spent casing out of the chamber, recharge the rifle which I found to have difficulty pushing the next round out of the magazine and back into the chamber. This happened repeatedly and even after 30 rounds, there was no change. I then decided to put my old BCG back into the rifle, loaded another magazine and it fired flawlessly. Just FYI, this is a buyer beware 308 bolt.
Failed headspace check
Tested with Clymer gauges in a Criterion barrel, this failed headspace. Would not close on the Go gauge. Might work in barrels with less tight tolerances, but you're taking a risk to buy this.
Extractor was horrible
If you like your brass, check the extractor. They said to send the entire BCG back. I ordered a JP extractor instead. Sucks that it was sent out like this.
Fails to extract. Does not cycle.
Failed to extract several brands of ammo. Brass stays in bolt. Jams into ejection port. Ruins brass. Something wrong with extractor. To sharp under lip, dimensions off? BCG works ok with original lr308 extractor and also the dpms gen1 upgraded extractor. So, totally useless out of the box. Requires replacement parts immediately to function. Ruins brass. Marks up upper receiver. Better off just buying a quality bcg from a reputable brand. Maybe buy this on sale and use the money you save to get a new extractor.
Does NOT work on sr25 DPMS guns !!!!!!!!
Just an FYI, purchased a Brownells ar10 DPMS BCG for a new AREO build. Worked OK with no mag, put in a magpul and a d&h steel mag and the bolt hung on the follower first, depressed follower thru ejection port and carrier itself does not clear either mag. Tried the BCG in a DPMS Panther ar10 and same issue. Put DPMS BCG in the AERO and no issue. Put both side by side and the cut on the passengers side is way different that the factory DPMS (sr25 pattern on both guns). Called Brownells and they say it SHOULD work in any sr25 type gun. Pen in pics show rail difference, square and smaller track, not angled also.
Dimensions Wrong Affecting Headspace
Actually Zero Stars - It was pretty, but on my specimen of this bolt, the individual bolt lugs measured .308" to .309" long and the bolt face recess measured .123" deep, which resulted in the bolt failing to reject a top quality NOGO gage in a well respected, high-end barrel brand. (WIN 308 headspace is 1.6300" to 1.6340", only .0040" total tolerance range and the barrel/extension combo gets part of that). I tried bolts from three other rifles in my shop and all firmly rejected the NOGO gage in this barrel. I talked with a Brownells' tech and he told me the lugs should be .312" and the recess should be .128" according to their manufacturer. My measurements showed this bolt to be way off the manufacturer dimensions. In my opinion, even if it were correct to the manufacturer's dimensions, it would likely still fail on the NOGO gage based on my experience (bolt face recess too deep). On many other AR-308 bolts and barrels used, I have found that bolt lugs measuring .312" to .313" long and bolt face recesses measuring .1245" to .1255" deep will headspace properly in good quality barrels. There is some info to support these dimensions on the web, but I could find no manufacturer dimensions. Rifle building hobbyists, BEWARE, there is no MIL SPEC for AR-308 rifles or parts, like on M4 and M16 parts used in AR-15s. Each AR-308 part maker chooses his own dimensions and tolerances. Every bolt/barrel combination should be headspaced for best quality, accuracy, and safety.
