Originally Posted by statjunk
I am thoroughly confused. My understanding is that my chamber is .002 over saami. The bump should be .002 so that puts me back at saami. I'm not saying I want to be at saami specifically. If the brass measured .006 over saami then I'd be bumping it back to .004 over saami. Isn't that what I'm supposed to be doing here?
Not sure what you mean by I don't need to do anything. I was told that simply neck sizing would lead me to trouble.
Before you fire for the first time the brass will be smaller than SAAMI specs. After you fire it is now the size of your chamber (Fire formed) and is the best fit to your chamber and most of the
time it is at the most accurate size. And will have no headspace which is in my opinion the best
for brass and accuracy.
A SAAMI chamber is one that is the exact size of the cartrige specification with "NO" head space.
but most smiths will add .001 or .002 to the overall dimension to aid in loading. different size
If your cartrige/brass is SAAMI spec. after firing then your chamber is not SAAMI spec. or you have no head space. (Head space is based on SAAMI Dimension + the head space dimension
The neck sizing issue is controversial and if not done right it can hurt you but Is the best method
to load consistant loads and to extend the life of your brass.
Remember , the less you work your brass the longer it will last.
Some people full length size every time, and some neck size 3 or 4 times, anneal. and full length
size. It is a personal choice and depends on what the person wants to use it for. (Full length
size for dangerous game and ease of loading, Neck sizing is best for accuracy and long range
hunting where consistency contributes to Accuracy.
The only reason I can see for bumping the shoulder is if you are loading hard/hot and the brass
will not chamber with out a lot of force.
To me the ideal chamber is one that is SAAMI spec. with .0005 to .001 Headspace.
J E CUSTOM