223 shoulder measurement

[gunner40sw]

Does anyone here loading 223 or 556 casings use the hornady head space comparator and if so are you using the A 330 insert and if so what measurement are you getting when you measure new brass and fired brass. The book says the measurement should be 
1.557 and yet when i measure even brand new brass i get 1.457

[SnipTheDog]

The headspace comparator measures to an arbitrary point on the the shoulder.  I can't imagine that there would be standards based based on arbitrary points?

[Farmer]

The brass I have sized to fit my M70 is 1.458-1.460. Any longer and they won’t fit. My other rifle has a larger chamber but it’s still only 1.480. You need to fire a case in your rifle, de-prime it without sizing the case and then measure it with your gauge. Subtract .003 and size to that dimension. Sometimes easier said than done depending on your chamber. 

[Ronemus]

Go here for the official SAAMI drawings.  They show 1.557" to the shoulder/neck junction, and the base to .330" dimension as 1.467".

[Ed F]

Running multiple AR's 

Measuring PMC Bronze 223 

1.) 1.520

2.) 1.530 
3.) 1.545

 

I bump to 1.520-1.500, press stretch comes into play on a 650/750

Also because of press stretch I now it through the press 3x

1.) Just deprime 

2.) Size/bump and trim

3.) Setup to load