The UK's Finest Independent Forum for Shooters and Gun Owners. Est 2010.

Hi everyone how are you, my question is this has anyone ever actually heard of a gun blowing up due to using 5.56 ammunition in .233 chambered guns, i have read all about it on the internet and the different pressures, and that both are measured in different ways saami etc but loads of lads at my club use surplus 5.56 x45 nato in their remington 700's i just wondered what everyones views on this practice were please

SAAMI list it as an "unsafe combination" here:

http://www.saami.org/specifications_and ... ations.pdf

Enough reason for me not to even think about doing it (though I don't currently have a .223). Suspect I could reload for close to the cost per bang of milsurp.

http://www.luckygunner.com/labs/5-56-vs-223/ this was quite interesting reading, im not planning using 5.56 myself, i was just curious as to the difference and know alot of lads using the nato stuff

To be honest, pretty much all I use in my Rem 700 and M4 carbine is mil surp 5.56....I think i have 3 different types in my cabinet at the moment, all work fine in both rifles apart from one batch that gives very tight extractions in the M4, but works fine in the Remington... no other signs of excess pressure.

.223 Saiga rifles for example can use 5.56mm ammunition with no problems as the ".223" stamping on the receiver was more of a marketing move for sporting purposes as the .223 appears more "sporting" than the military sounding 5.56mm.The chamber is actually the same as a 5.56 NATO chambered AK-101.

Maybe you should think about having the chamber cut to Wylde specifications, ooman.

The .223 Wylde chamber has the external dimensions and lead angle as found in the military 5.56×45mm NATO cartridge and the 0.2240 inch freebore diameter as found in the civilian SAAMI .223 Remington cartridge. Rifles with a .223 Wylde chamber will accept both .223 Remington and 5.56×45mm NATO ammunition. The case is actually the same in both .223 and 5.56, it's just the chambers that are different between military and civilian rifles. The Wylde chamber shoots the relatively long and heavy 80-grain bullets very well. Have a word with Dave at Valkyrie Rifles...

meles meles wrote:The case is actually the same in both .223 and 5.56, it's just the chambers that are different between military and civilian rifles...

Sort of.
Externally the case IS the same, but they do differ in case wall thickness though.

I wouldn't advise using 5.56 nato in a .223 rem. I do however, have no issues with using XM193 or M193 5.56 in a .223 Rem.