For a very long time I have loaded my 303's with 174 SMK's and driven them at or near 2,440FPS which is the velocity the standard Mk VII ball round was.
What I had noticed is that at this velocity it did not match up at all to the sight graduations on the sight ladders of either my Mk III's or No.4's.
As you found that at times it equated to a 100 to perhaps 200yd higher setting on the ladder to get POA/POI and this had me a bit perplexed until I got a light bulb moment.
I was consulting the latest ADI book and reading about the new propellants coming on line and how they are lowering the temp of the flame and also incorporating an additive to reduce copper fouling.
Got to thinking about BC's and this is where I think I have erred all these years and my thoughts are thus;
There is no comparison between the MK VII ballistics and the reloads we have due to better powders, different rates of burn as cordite burned faster & hotter the BC's of the projectiles are streets apart.
So here is what I think if we have an SMK that flies flatter than the MK VII projie at the same velocity then it will hit LOWER on the target at a given range by that simple fact it flies flatter.
So in order to get the POI we raise our sights because we need to be on POA/POI but it defies logic as we have a bullet flying flatter so we have to lift up the sights.
Sooooo what I am going to play with and be a secret squirrel till I get it right is load down the rounds to minimum and go from there (NOTE: Never go under minimum load data)
Will see what happens and I will report back and as we only go back to 600yds in our matches keeping above the tran-sonic will not be a problem.
What do you chaps think is my summation correct it sounds bizarre I know but think about it and you will see I feel the theory has merit.Information
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