looking to buy a AR-15

[dutchman]

Here's a good barreled upper assembly: http://palmettostatearmory.com/inde...ped-upper-without-bcg-or-charging-handle.html

 

[chans]

http://www.ar15.com/forums/t_3_118/400993_.html

"A Wylde chamber, which is a mix between .223 and 5.56. The 5.56x45 NATO is NOT exactly the same as a .223 Rem. The 5.56 spec allows for slightly longer chambers for higher pressures. The .223 has a tighter chamber around the neck and is shorter which allows for a bit better accuracy. You can shoot .223 ammo in a 5.56 chamber, but it is DANGEROUS to shoot 5.56 (surplus for instance) ammo in a .223 chamber. What the Wylde chamber does is allow for 5.56 ammo with slightly tighter chamber for better accuracy. So you can shoot both 5.56 and .223 safely with good accuracy"

.223 and 5.56 have identical exterior dimensions. The longer throat on the chamber of the 5.56 is because of the heavy bullets the military uses like 62gr which if you shoot in a tight .223 throat, 1/9 twist can cause more pressure but if you have a 1/8 or 1/7 twist .223 barrel it is designed for 68 and 77gr and the 5.56 will not be an issue. The difference is in the interior capacity since the 5.56 has thicker walls mainly by the base to prevent case separation. How you get more pressure is if you put the same grains of powder but have less room more pressure builds.

.223

 

[jentzschman]

I am a big believer in building them. It allows you to get to know the weapon much better and its fun, IMHO. I build my AR for ~800. I am actually looking to start building another one.

 

[chans]

And since everyone likes PSA read my bottom picture about the original .223 that was adopted as 5.56 with a 55gr bullet designated the M193 which all but the 62gr armor piercing rounds are for surplus. Since the hard steel core should not be shot out in the desert for sparks when it hits on the rocks and causes fires anyways.
http://palmettostatearmory.com/inde...6x45mm-nato-55gr-fmj-120rds-xm193-lbc120.html

Pretty much almost all your surplus is old school .223
If you check the reloading charts you will find many .223 going faster than 3250fps that is standard for the 5.56 out of the same barrel length. Been reloading both the .223 and 5.56 cartridge and shooting them for a quarter century.

 

[chans]

If you have not found one yet here is a DPMS for 439.00 and free shipping on first order when you set up an account.
http://grabagun.com/catalog/product...GrabAGun+-+DPMS+Refurbished+Rifles+-+Blow+Out!