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Is shooting 40 much different than 10?

Discussion in 'The 10 Ring' started by matai, Apr 24, 2010.

  1. matai


    Jan 14, 2009
    I ordered a 40 conversion barrel for my G20. Will shooting target ammo feel much different between the 40 and 10?

    Will there be any point of impact differences?

  2. Richard Simmons

    Richard Simmons American Icon

    Jul 29, 2006
    Can't speak to the G20 but in my S&W 610 shooting 180 FMJ .40 after shooting 180gr Double Tap loads is like shooting .38 Special in a .357. On the flip side I can't tell much if any difference between standard .40 and 10mm loads of the same weight, probably due to the fact that most, off the shelf 10mm ammo, including more than a few "self defense" loads seem to be pretty watered down.

    With that being the case I've not seen much chainge in POI between the two calibers within the same bullet weights. Given that my S&W 610 is the 3" model, most of my target work has been within 3-10 with a little bit at 25yds. The change in POI might be a lot more noticeable at say, 75-100yds.

  3. HOV


    Mar 5, 2005
    Shooting .40S&W from a 10mm to me feels like shooting 9mm from a 9mm.

    Maybe it's the mass of the slide that makes all the difference, but I think it's a great match and I have no regrets dropping the $160 for the KKM conversion barrel.

    I'm not sure about POI because I normally shoot close range.
  4. HOV


    Mar 5, 2005
    Also - if I were to choose a conversion barrel for carry (I wouldn't, but IF...) it would be the 10mm-.40S&W for sure. I believe the reliability of this conversion is one of the best.
  5. DrtyHarry


    Sep 26, 2007
    Personally, I would not carry an aftermarket barrel in my EDC.

    If you said you put 5000 rounds plus downrange with the barrel and it worked fine, I might think differently. Not sure why you would want to carry the bigger G20 and not carry it with HOT SD 10mm loads. The .40 conversion should be left for range fun and cheap plinking, IMHO. In any case, good luck finding a good barrel!

  6. HOV


    Mar 5, 2005
    Of course not.

    But... as far as carrying it with HOT 10mm loads, I do disagree. I think medium-hot 10mm loads are way more accurate and controllable than the nuclear stuff and I much rather carry stuff that I can shoot controllably and hit my target.

    Medium-hot 10mm loads are still greater than anything .40S&W can produce, and are also hotter still than many .357Mag loads... that's the beauty of 10mm.
    Last edited: Apr 24, 2010