Duckbill Done Right? Testing the A&W Diverter Shotgun Barrel (w/ Matt Haught)

The A&W Diverter was designed by Clifford Ashbrook and Wilson Wing to change a shotgun’s circular pattern into a horizontal linear one. They applied for a patent in 1967, and it was granted in 1970 (US Patent #3,492,750). Their invention was similar in purpose to the “duckbill” chokes tried out by the US military in Vietnam, but done with a lot more engineering. Two versions were made, a sporting one with a 2:1 shot pattern and a military one with a 4:1 pattern. Thanks to Mike Carrick of Arms Heritage magazine, we have a Remington 870 barrel with a 4:1 Diverter to test out today.

Joining me for the experiment is Matt Haught of Sym-Tac Consulting. Matt is a dedicated shotgun trainer who is slowly converting me to have a better appreciation for smoothbores…

For a look at the original published data on Diverter performance, check the May 1970 issue of Guns Magazine:


  1. Muzzle mods on shotguns is a science on its own. I was one time heavily interested in the subject (and read all the stuff I could find) and can appreciate its complexity. In this case what Ian’s got is useful mostly for birdshot. Unless I miss something, I do not see its use for bucks. At extended ranges… maybe.

    What strikes me though is Mat’s skills; he is a perfect shooting buddy.

    • No. 4 buckshot, the smallest size of buckshot, e.g. 27x .24 cal. pellets, each weighs about 20-gr., or about half the weight of a .22 lr bullet.

      This was often used in the United States “back in the day” by urban police and detectives and stake-out squads due to concerns with over-penetration in apartment buildings and whatnot compared to the “fight stopper” 00 buckshot. Departments that were concerned about armed encounters around vehicles continued to advocate 00 buckshot in cruiser shotguns.

      My admittedly limited understanding has it that while the UK used 00 buckshot in Malay in the counterinsurgency against the MRLA there, finding that a Browning Auto-5 mag dump by the point man in an ambush situation was just the thing in triple-canopy jungle fighting, that the U.S. in Vietnam thought No. 4 would result in a denser pattern of smaller shot at longer combat ranges, and so advocated that buckshot to supplement 00 buckshot. The Ithaca 37 with “duckbill choke” used by the navy was intended for use with No. 4 buckshot.

  2. I think Matt’s characterization is a bit off: at reasonable ranges, the patterning of the AW seems like it would practically guarantee hits regardless of minor azimuth errors (jerking the trigger, etc.) or unexpected target motion – EXACTLY the questions the defensive shotgun is meant to answer.

  3. I must be really old. The idea in using bird shot for riot control was to shoot very low – feet, ankles, and shins. Too low was better than too high. You weren’t trying to kill people, you were just trying to get them to go away.

  4. I could see selling it for bird and rabbit hunting, but I think it would not be a strong positive. On crossing targets you would be more likely to score a hit if your lead was off a little, but you would have to be dead on in terms of elevation and it didn’t look like the density was ideal. For skipping birdshot off the pavement into a crowd of rioters? Greaves could make a comeback.

  5. The “donut hole” is caused by wad “push through” at the muzzle. The late Bud Weisner of Simsbury, Ct. invented and marketed his Jet Away choke during the 1960’s and 1970’s, which will squirt buckshot like a fire hose. I have one, but have never tried it on buckshot.

  6. Hello I have a winchester model 1200 pump with a A&W diverter on it. Very Cool had the gun since 80s never fired it. To clean just collecting. Was a police gun.

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