Don’t both rounds have the same case head diameter?
What’s the difference between the bolts?
I don’t have my 5.45 bolts to compare,they are different. I can post pics on friday.
I’ll be waiting until Friday also to see the difference.
O
Bolts are different and the extractor is different:
https://www.m4carbine.net/showthread.php?p=447121#post447121
I will take some pics when i get to the shop in the morning.
Allright I promised pics and here they are. The first 3 shots the bolts are identical looking to the naked eye.
I looked them over with my dad they both looked the same. Knowing that not to be the case, I pulled out the calipers. Upon measurement it was revealed to be bigger on the 5.45x39 rim.
In theory a competent machinist could remove material and make a 5.45x39 bolt face very easy.
I have two 5.45x39 bolts and two barrels. I promised long ago i would get some ammo and build some uppers.
I am still planning on it I just need to get the parts,it will get done just don’t know when I could probably build one if I dug in the parts box.
I will put it on a Full-Auto lower and see how well it runs.
With the cost of 5.56 it does not get flipped to the fun button very often.
Enjoy.
thanks for the pics.
No problem.
That’s funny. I’ve got a 5.56 extractor in my 5.45 rifle right now.
So far after 1k+ rounds, no problems at all.
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.
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.
is 5.45 still widely available and cheep?
Yes 189.00 per 1080 at ammoman.
Dude it’s cheaper at Aimsurplus…
I am sure it is that was the last price i remember.
$130 / 1080 at AIM Surplus.
And AIM won’t try and claim it’s a Viet-Nam bringback either.
…that’s 10-years-ago price for 223
man, i’ve gotta get me a 5.45 barrel and bolt
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.