5.56mm and 5.45mm ar15 bolts are different?

[n00b]

Weird. When I measured them the 5.45 was had a bigger bolt face area.

Well the bolt is different for sure but a 5.56 extractor will work in a S&W 5.45 upper. At least that has been my experience and many others as well.

The thing is that a 5.56 extractor will cost about $10-$15. According to another member here, they go for $40 from S&W directly. Which is a huge difference. My original extractor broke at about 1k rounds and S&W said I had to ship out the whole upper and the wait time could be from 3-5 weeks!

So I did a bit of reading and ordered a 5.56 extractor. I thought if it doesn't work I still have other 5.56 uppers I could use it as a spare. But once installed it worked great!

Took a couple of rounds to get broken in because the first few rounds would fail to eject but once it was, it was smooth sailing.

[Infidel74]

I misread what you said,reading back I see it. Good to know. My dad ordered a couple barrels and they came with bolts. I need to get on this project, but he tossed another few gun projects my way that are more important. Soon, soon.

[bkb0000]

is 5.45 still widely available and cheep?

[Infidel74]

Yes 189.00 per 1080 at ammoman.

[n00b]

Yes 189.00 per 1080 at ammoman.

Dude it's cheaper at Aimsurplus...

[Infidel74]

I am sure it is that was the last price i remember.

[justin_247]

$130 / 1080 at AIM Surplus.

[Heavy Metal]

And AIM won't try and claim it's a Viet-Nam bringback either.

[bkb0000]

$130 / 1080 at AIM Surplus.

...that's 10-years-ago price for 223

man, i've gotta get me a 5.45 barrel and bolt

[ruf]

Well the bolt is different for sure but a 5.56 extractor will work in a S&W 5.45 upper. At least that has been my experience and many others as well.

The thing is that a 5.56 extractor will cost about $10-$15. According to another member here, they go for $40 from S&W directly. Which is a huge difference. My original extractor broke at about 1k rounds and S&W said I had to ship out the whole upper and the wait time could be from 3-5 weeks!

So I did a bit of reading and ordered a 5.56 extractor. I thought if it doesn't work I still have other 5.56 uppers I could use it as a spare. But once installed it worked great!

Took a couple of rounds to get broken in because the first few rounds would fail to eject but once it was, it was smooth sailing.

Good to know! The geometry is definitely different, but if it runs then great! One less spare to keep around. Mine is bound to go south soon.