The lonliness of the long distance Auto Mag

How many here have fired their Auto Mags at long-for-pistol distances? And what results have you had? The question is posed upon my reminiscing of a shooting day last year. In question is a 10 1/2", .44 AM pistol. I was doing some routine chronographing and cyclability testing, usually a sub 20 round affair, when I noticed the steel practice container in the distance as I was putting the gun away. This container was a remnant of some other shooters, but it measures some 16" in diameter and 24" in height; This steel makeshift gong delivers a kind, reaffirming chime everytime it's hit. It is audible past 500 yards. We've used it in the past to test surplus military rifle sights, and to zero-in scopes. From our postion we have verified it to be 320 yards. Returning to the Auto Mag.....as I was putting it away, and espied the rusty whiner, I thought why not try my last five rounds on the old bucket? Well, being a somewhat devoted Kieth man, using the front sight hold-over method I tried a few shots. The load is a LaserCast .430" 240gr. Semi-Wadcutter over 19.8 grains of H-110. This load does about 1390-1440 f/ps from this barrel. The first round struck the twilight of the metal and the ground. The subsequent two rounds row-called in with their positive ringing tone. I stopped, put away the last two rounds, and scratched my head. I took no credit with the bystanders, and simply decided the gun was inherently hexed in a good way. I have made a practice to shoot pistols at long distances since I started shooting, but always had to tailor loads for this kind of accuracy. I was kindly vexed by the instant precision. Do I have a lucky barrel, did the load just hit the gambler's odds and make a great combo.......or......are Auto Mags just superbly accurate. Your thoughts. I ask modestly, for in all respects I do not wish to factor in to the equation. I do understand Mr. Jurras made common practice of this, and would be hard pressed to deny I didn't feel Jurras'esque as I accomplished this. None the less...........How 'bout them Auto Mags?