Shot Size Selection


Lately the shot size of 8 1/2 has come into favor more and more. I would like to know your thoughts on it, as well as how it would change your choke recommendations of using light mod from 20-35. Would the additional pellets allow an IC to 35 yds? Would you be loosing much if you even used 8 1/2 in a skeet choke out to 20 yds?

The other trend “so to speak” is using 7 1/2 for everything. The argument for this is that 7 1/2 will break everything from an edge on rabbit to a 45 yrd crosser so why bother with anything else. My question is if you do use 7 1/2 for everything what are you giving up in pattern size? Also what would be the optimum choke selections if all you used was 7 1/2s. For all the above questions assume an 1 1/8 of shot.



Dear Mike,

Shot size selection is based on a combination of hard physics, fuzzy logic and primal emotional need. It is seldom completely rational. In ways its like a war stratagem, always based in incomplete information.

I have no argument with the guy who says that he will use full loads of #7-1/2 so he never has to waste the time thinking about shell selection again. He’s making a technical sacrifice in exchange for an emotional benefit. It’s the same argument for the guy who shoots a fixed Full or Mod choke for everything. I’m sure that he knows that a Cylinder Bore choke and a full load of #9s is gives him a larger percentage pattern for the 20 yard skeet shot, but on balance he feels that eliminating certain decisions (such as choke and shell selection) will help him concentrate on more important decisions (such as target analysis).

Another shooter may feel that his target analysis is well in hand and he wants the largest effective pattern possible. For him, it is best to optimize choke and shell.This means changing as the situation demands. This attitude may also be best for someone who isn’t exactly sure what to do and figures that choke and shell is the only thing he has control over, so he might as well tinker with it. Many newer shooters fall into this category in sporting clays.

So what do you pick. In pellet energy, the following all develop 1 ft/lb of energy when started at a three foot velocity of 1200 fps:

#9s at 21 yards

#8-1/2s at 27 yards

#8s at 34 yards

#7-1/2s at 42 yards

If you are going this route, you now have to decide how many pellets producing how much individual energy you need to average to break your bird. You also need to decide what your acceptable fringe would be. Warren Johnson’s most excellent “Choke Chooser” lays all this out for you. Warren uses an acceptable fringe of a 95% chance of a one pellet strike, which equals an 80% chance of a two pellet strike which equals a 50% chance of a three pellet strike. If you use this fringe definition (and it’s a very reasonable one in the real world) and know the exposed area of your target (how “turned” the bird is, ie edge-on vs full-open and in between), once you add required pellet energy (and I think about 1 ft/lb per pellet is as good a number as any), you can calculate how big a killing circle you get with any given choke. I think that Choke Chooser is a neat little $10 slide rule deal and I use it often. Ed Lowry’s excellent “Shotshell Ballistics for Windows” computer program give advanced ballistic analysis in many fields, but basically echoes what Choke Chooser says.

What you learn right away is that you do give up some effective pattern if you don’t change the choke and shell for each presentation. At 40 yards cylinder bore and #9s don’t equal Full and #7-1/2s. Same at 20 yards. In each case, the wrong selection nets you a considerably smaller killing pattern. In between is in between and how much you want to simplify is up to you.

#9s and Cylinder Bore will break 50 yard crossers. I promise you they will- some times. That combination just won’t break them as consistently as proper choke and shell selection will. That’s the problem with sporting clays that skeet and trap don’t have. Sporting distances change with every shot. Everything works some of the time and nothing works all the time, so you get people who swear that one particular combination is ideal without really having any base in long term statistical feedback. Trap and skeet shooters know what works because they have shot a million-billion identical shots. They have hard numbers. Sporters don’t because shots are never the same.

The bottom line is that I can’t tell you what’s best for you. For myself, I keep it simple, but not totally simple. I tend to do my target analysis starting with the choke required for the particular distance/target exposure. Then, once I select the choke, I let the choke dictate the shell. I tend to pair Cylinder Bore with #9s, Light Mod with #8s and Full with #7-1/2s. Not always, but usually. I’m not saying that you should do this (and you might not if you saw me shoot), but it works for me. For edge-on 110 targets, that works out to 20, 30 and 40 yards or “near”, “normal” and “far”. Put another way, at skeet distances I use what skeet shooters use, at trap distances I use what trap shooters use and in between is in between.

I won’t argue that my approach is “best” or even “good”, but it is what I have come to use. If fills my emotional needs, charges my psyche with optimism and has some vague basis in ballistic science. If I shot like Digweed or Faulds, I’d probably use Full choke and #7-1/2s for everything too. But I don’t, so I don’t. I need all the help I can get so I scheme, plan and pretend.

Best regards,

Bruce Buck
The Technoid writing for Shotgun Report, LLC
(Often in error. Never in doubt.)

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3 Responses to Shot Size Selection

  1. jon bastable says:

    Bruce: Off to Firesteel again this year? I’m headed to Murdo on Wednesday. Not expecting a great shoot as the birds haven’t recovered from the drought.

    Great article on shot sizes et al.



  2. We don’t have one anymore. Perhaps we’ll rev it up again sometime in the future.


  3. says:

    Where is the store located? I don’t see a link


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