I have a Bushmaster Ar-15 which says 5.56/.223 on the barrel.I have some ammo which reads 5,56x45.Can this ammo be used in my AR?I thinks so but have had a couple of people tell me otherwise.Thanks

Wiley - yep your okay. 5.56x45mm is .223 Remington. I think the confusion may be the 5.45x39mm round which is the Russian round for the AK74/SAR2. Now that SHOULD NOT be used in your AR.

For most intents and purposes 5.56x45 = .223 Remington

Shoot away

Yes, this is the correct ammo.

Thanks.That is exactly what I thought.I was doing some coyote hunting today and as a coyote came flying around a corner and I missed,my follow up shot jammed.Some of the ammo I had in my clip was green tipped and when I disassembled the weapon I noticed some green flecks which I'm guessing  kept the casing from ejecting.(who knows).In any case I remembered having some of this s/b 5,56x45 and thought I would use some of this instead of the old green tipped stuff.Thanks again.

Wiley, that green tipped stuff should be SS109 'Penetrator' steel core, 62gr.

The S&B should be fine as well, and probably a better choice for hunting coyotes anyways. That SS109 stuff will zip right through'em. Probably spend just as much time trying to find him as you did stalking him.

Check that magazine as well, the failure may have been a result of a weak mag spring. If the cartridge didnt eject, check the extractor/ejector and spring on the bolt. Is it a new rifle? If so, maybe just working her out a bit more will solve the problem too.

The magazine has been loaded so it might be a weak spring???The rifle has probably only had about 150 rds thru it also.Could just be one of those "shit happens" things.Threw 4 rds of the s/b in the magazine and it fired as quick as I could pull the trigger.The next time I tried to pull the charging handle it felt like there was no spring there but then suddenly snapped back as I messed with the charging handle.Who knows.All seems to be ok now.Thanks.