Master Po's data isn't based on factual velocity and pressure measurements like military ammo is.
Bart,given your background,very few people have had the resources you have had.
Rest assured,I'm here to learn from you,rather than argue with you.
I appreciate your contributions.
When I received my Garand, I was aware of the port pressure issue,so I set about finding some appropriate load data.
I found Master Po's page. On the page it says "Provided by the NRA" Maybe I'm wrong,but I connect that to a long history of DCM,CMP,and the NRA sanctioning of competition providing quite a pool of experience anout what works in a Garand.
I enjoy shooting my Garand. I don't shoot competition. The longest convenient range I have access to is 300 yds,unless I go to some ranch land I can access.
My needs are met by ammo that does not beat up the gun,is reliable,and acceptably accurate.
For myself,at the "stakes" I shoot my Garand,there is no trophy on the line.
In your case,trimming 1/2 MOA off the groups or gaining 70 fps are significant to winning.
In my case,a CMP rack Garand n decent shape levels the playing field.Its not all about focusing on the rifle or the ammo,
Of course,your primary asset was shooting skill. But in your league,to be competitive,the best in rifle and ammunition might be assumed. At least,there aren't any excuses.You shoot with the Big Boys or you don't.
For most Garand owners Its more on learning to shoot it to its potential.
I stock H-4895 in my teloading room for other purposes. I stock Nosler 168 gr Custom Comps for other purposes. I buy WW virgin 30-06 brass for other purposes.
I stock the CCI mil spec large rifle primer for other purposes.
With what I already have,I can load 46 to 47 gr of H-4895 behnd a 168 gr Nosler CC and have pretty good ammo that meets my needs.
Frankly,I did not devote time to learning if RE-15 or Varget or 4064,etc would serve "better" Same with 155 gr MK's or 175 g rMK's,etc.I found "good enough" to meet my needs. If shooting my Garand was my life and passion,then relentless improvement would be the order of the day.
But its casual recreation.
If I had reason ,or opportunity,to shoot 600 yds +,I'd probably switch to 175 gr MK's.
If there is any good reason to switch my load,especially for the good of the rifle,I'd be happy to know about it. Thanks