My head hurts taking all this in...how about an amusing anecdote for those of us in Rio Linda? Some years back when the Commonwealth countries were still using .303's in competition, it was common knowledge that the Mk7 .303 174 gr ball round was barely capable of holding 2,5 moa at 100 or 200 yards. But, it got better at 300 and , Katy bar the door at 600, theory was the damn thing straightened up and flew right. Embarrassing several competing countries, including us Yanks.
That's not quite the whole story. The Brits harnessed a phenomenon called "Positive Compensation" which meant that Enfield's could be tuned to release bullets at different points of the vibration depending on the velocity of the bullet. The slower bullets would exit the muzzle when the muzzle whip was high and the faster bullets would exit the muzzle at a point when the barrel whip was lower. This would cause the slower bullets to NOT impact lower as you would expect, and the bullets would converge at a given range (but they had terrible vertical at short range). This apparently was a byproduct of the rear locking action and the two piece stock. Creighton Audette mentioned that the M14 compensated slightly at 600 yards as well.
The effect worked in the vertical plane only and Enfields were tuned or "regulated" to take advantage of that effect at 1000 yards commonly. The most well known "regulator" of Enfields is G.E. Fulton.
The effect only worked when there was a wide variation in velocity as was present in the .303 ammo of the day and in Brit 7.62 Ball with large spreads like Radway Green (RG) ammo. This effect was negated when match ammo with decent velocity spreads started being used. I'd heard of Regulated Enfields being used in the 1992 Palma without good effect. I think the Enfields were hung up for Palma matches there after due to match ammo taking over in Palma.
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![[Linked Image from i.imgur.com]](https://i.imgur.com/hopFwlQ.jpg)
