i'd just like to verify what i know...or don't know about headspacing...

 

while everyone thinks 223 and 556 "are the same", they do have differences and while there are go, no-go and field headspacing gauges for 223, there are only min and max gauges for 556.  my barrel is chambered for 556, which leads me to believe that i should simply check min and max.  does this "min-max check" have anything to do with what caliber ammo i use in the firearm?  meaning, there is a min-max check for 556 and a go, no-go, field check for 223...?  i understand what head space is, i'm just now sure about it's relationship to checking it...in regard to what ammo i might be using and if it makes a difference?

 

so...checking a 556 chambered barrel for min-max headspace, as long as my bolt and barrel check out, i can safely fire 223 or 556 ammo...correct?

 

probably over thinking things, but learning is fun

 

 

I am certainly no authority but AFAIK, you can shoot .223 and 5.56 in a 5.56 chamber but you can only shoot .223 in a .223 chamber?

Yes. You can shoot .223 in a 5.56 barrel but not the other way around.

yes, that is correct.  so i would assume if a 556 chamber is headspaced per min-max, you can use 223 ammo in that headspace and not have to check it for 223...?  not sure if that makes sense, i would assume a properly headspaced 556 chamber, spaced per the correct min-max for that caliber...223 will also work with no issues.  i think i'm saying that right.

 

a lot of threads online, people are headspacing with just go and no-go gauges (which are typically 223/556 gauges - which in reality should not be the same thing), and if you're going to headspace at all, that seems incorrect.  they should be checking with go and field gauges, as no-go is still within spec, just not optimal and might be a sign that it's time for some new parts.

 

once again, i'm probably over thinking this.  i don't really want to worry about headspace at all - but if i'm going to do it, i want to know what the correct way is and why.

 

food for thought:

 

http://ar15barrels.com/data/223-556.pdf

well if anyone needs to check headspace for a 556 chambered barrel, i'll soon have the tools to do it.  i was able to find Forster gauges on ebay so i pulled the trigger (pun intended) and picked them up.  i have another stripped lower, so i know i'll be building at least one more rifle after this, plus whatever my friends decide to build in the coming months, so it seemed like a purchase i would get some use out of.