This fellow had been a machinist in his younger days so he did the job properly. He used a set of piloted adjustable reamers taking a couple thousands off, then polishing and then patterning. True to being thorough he did ten patterns of each tube and said if he got one bad one out of the ten he would do a five extra. I can only guess he did hundreds of pattern before he was done. He did this for three sets of tubes. He only shot the "selected" shells for competition and serious practice. The rest of the time he shot reloads like the rest of us but he patterned them extensively as well. Them man was dedicated to say the least.
I've got to find that choke tube I bought. It looks like a figure eight laid sideways with two projections, one in the center top and one center bottom. The projections were designed to retard the wad, while the pattern was supposed to be a flattened oval. What the projections did was shred the wad so plastic confetti would float away and the pattern was crap to say the least.
