I've been shooting a Trulock .680 choke for a couple years, but have been advised that a more open choke may perform better for the 'larger' shot that I'm using. So, I bought the next size up and did a comparison.
Gun: Remington SP-10, 25" barrel
Shells: Nitro Ammunition TSS #7.5 (2 5/8 oz.)
Choke #1: Trulock Turkey Choke .680, non-ported
Choke #2: Trulock Turkey Choke .700, non-ported
I took 2 shots with each choke at 40 yards. Found the greatest pellet mass and drew a 10" circle. I cleaned the barrel with Butch's before each of the 4 individual shots for experiment integrity, though I thought that might be going a little overboard (but it wasn't).
Shot 1 w/ .680 - 246 pellets in 10" circle
Shot 2 w/ .680 - 175 pellets in 10" circle
Shot 3 w/ .700 - 310 pellets in 10" circle
Shot 4 w/ .700 - 312 pellets in 10" circle
The more open .700 choke clearly outperformed the tighter .680, at least using my gun and that ammo. And it wasn't just the 10" numbers. I knew when I was 15 yards out walking towards that first .700 pattern that it was much better. The pattern just looked more concentrated, more even, and far less flyers. The repeated performance on the second shot confirmed it.
What else did I learn? How important it is to shoot with a bright, clean barrel.
After settling on the .700, I proceeded to sight-in my red dot without cleaning the barrel. The difference was immediate. Even the second shot without cleaning I could notice more flyers and a slightly more open spread of pellets in general. And that continued incrementally through the 3rd and 4th shots. Still a great killing pattern, but, shooting a clean barrel does make a difference in performance. Many of you probably already know that, but it was impressive to me.
Anyway, just passing this along if it might be useful to someone. And I do hope it helps keep the 10 gauge discussions going.
