Re: 6.5x47 OCW Test 8.5.2011
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: doubled</div><div class="ubbcode-body">
I went back the following day and did more testing with 37.3 and it was holding less than .5 MOA out thru 400 yards. I am going to go back and stretch out a little more this weekend but I think i have found the load.
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You may, or you may not have found THE load. I don't see enough evidence to suggest 37.3 grains is your OCW, especially since just a mere .3 grains above that scatters all to shit. Do you know where 37.4 and 37.5 impact?
In that size case, you need in the neighborhood of .4 grains above your OCW, and the same range below your OCW, that all shoot just like your OCW.
In other words, if you were to load 36.9, 37.0, 37.1, 37.2, 37.3, 37.4, 37.5, 37.6, and 37.7, albeit singularly, two of each, three of each, or five of each....ALL of them WILL group in the exact same point of impact with no unexplainable flyers.
You don't have that because 37.6 scatters, and I'm betting 37.5 and 37.7 scatter too......37.3 is NOT the winner simply because it groups nicest. It's the nut the blind squirrel found....no offense. If 37.3 is anything it's toward the upper end of the second to the last node. I'm thinking there's another one with more velocity.
You cannot say you kept going up with your R&D until you found the first sign of pressure, which is something I HAVE to know in a load workup. Someone here mentioned a test which determined 38.6 as being the pressure limit they found. It's my overall experience (going on 10 years now using Dan's methods) you will find a good useable node just shy of that pressure limit....so the upper end of the fastest OCW window will be right there close to but not yet at a sticky bolt or a flattened primer or a swelled pressure ring.
If I were you, and I was you wanting to say I found my true "OCW", then I'd go back to square one and start over. All is not lost though as you do know what some of it will do, but you need more evidentiary holes in the paper to prove it out.
I'd go back to 36.6 and work up in .2 grain increments (.1 grain increments won't kill you either) all the way up to the very first hint of pressure. It can be done easily with two or three shot groups of each charge weight, if you can shoot. Do that exactly so you have more data and you will see better what the harmonics are doing with your barrel.
My prediction is 36.6 and 36.7 will shoot similar to 36.9, the second to the last node is from there up to 37.4. 37.5 through 37.7 will scatter like 37.6 did. 37.8 will begin to settle down again, the center of your fastest OCW will between 37.8 and 38.5.....so 38.1, 38.2....ish?
Im betting heavy odds here.............
