Well it is time to try my hand a loading a FEW 124g Xtreme Rn loads. After I find the Max OAL and subtract .015 to find my OAL.
Whoa, right there !! Backup.
This is NOT what we said. You want to find the
Optimal OAL, which lies somewhere between the
Maximum OAL and the
Minimal OAL. No one said the Max OAL was the
best OAL.

When you find Max and Min OAL, then there is a zone of usable lengths that fall in between those 2 numbers. Try to envision the OAL as a number line, as the chart above illustrates. Sometimes, the 2 numbers are so close together that the Max OAL becomes the Optimal OAL,
but that is fairly rare if you are using the correct bullets. In most instances you have a decision to make based on many, many factors.
Will be using Winchester 231 powder starting @ 4.1gr. Is this a good starting point?
No one can say, for the simple reason that you haven't picked an OAL. The
Starting Load generally comes from the load data in your manual, in concert with the OAL you choose.
As we saw in your first attempt, due to your very short OAL, the bullet was buried deep into the cartridge case. That affected chamber pressure, therefore the load data should have been modified by moving the load window downward.
The load data in the manual is not some type of Golden Rule. It is not
your recipe, it is
their recipe. If you change any aspect of their recipe, then you might have to modify it to become your recipe. Chief among those changes (the Number One prime suspect) is the OAL and bullet length... because they affect
Chamber Pressure in a big way.
Remember
Chamber Pressure ? We've been talking about it for 2 pages now, but from your latest post, it doesn't seem to have sunk in just yet. I don't want to scare you, some reloading is straight out of the book and very easy. However, most of it takes a little more thought. You must
consider the mitigating factors. In order to do that you first have to
recognize the mitigating factors.
I'm not fussing at you. I'm trying to get you to begin a mindset and thinking process that will lead to a responsible and safe way to reload any cartridge. You wouldn't drive the kids all the way to Daytona Beach before you checked on hurricanes, shark attacks, and local accommodations. In the same way you'll be much better off the sooner you develop a similar mental check list for reloading.
So that I can put this in language that you'll understand, why don't you tell me what your occupation is, please.
