7.62x39 vs 300 Whisper

Discussion in 'Class III' started by jds324, Feb 24, 2011.

  1. jds324

    jds324 G&G Newbie

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    Hey all, this may have been covered, but I'm not finding much useful info on it. Independant of rifle, why would subsonic 300 Whisper be any better than subsonic 7.62x39? If I understand everything correctly, velocity for subsonic has to be around 1,000 fps (given temp, elevation, etc.), so the only real variables will be bullet weights and BC (again, assuming similar rifling, etc). So why would a 200 grain 300 Whisper fly and better than a 200 gr 7.62x39? I keep hearing people make broad statments like 300 Whisper is the greatest thing out there, just trying to figure out why. Is it simply because it is a pretty easy conversion on an AR? I'm a bolt rifle guy, so none of that matters to me.

    question 2: assuming the above assumtions are correct, why would anyone make a suppressed 223/5.56 when a suppressed 22lr shoots only a slightly smaller bullet weight wise? (40-60gr 22lr vs 40-80gr 223).

    Thanks guys!
  2. Rex_Lee

    Rex_Lee G&G Newbie

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    I hear you. Why is a 200 grain 300 whisper any better than say, a 200 grain .357 at 1000 fps? You could make the case that the the .357 was better, since it is .357" instead of .308" or whatever exact bore size the .300 whisper uses....
  3. WisconsinHunter

    WisconsinHunter G&G Newbie

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    Its easy to convert an AR to 300 whisper or 7.62x39. Just swap out the upper and you're good to go.
  4. jds324

    jds324 G&G Newbie

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    Sure, but why do I keep hearing about the superiority of 300 Whisper if it shoots the same size bullet at the same velocity as 7.62x39?
  5. jds324

    jds324 G&G Newbie

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    Here is my guess as to the hype around 300 Whisper (granted I've never shot it)

    It has a cool name
    It can use ar mags and bolt faces (but requires a new barrel, so not much different than a 7.62x39 upper)
    It uses the more popular .308 bullet instead of the .311 of the 7.62x39
    It has a slightly smaller case capacity than 7.62 (more a function of powder choice)

    All of these could be considered advatages, but ballistically I see no difference.
  6. Johnnycat

    Johnnycat G&G Newbie

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    I'll take a shot at this. Mind you - I've not shot either suppressed. But I do hear that the 300 whisper is the cat's meow. Both bullets are subsonic and would not make any difference.

    My understanding is that even though it's suppressed there is a sound of the gas from the ignition - like a pellet gun or airsoft. The suppressed sound of the Whisper is less obvious due to something - the efficiency of burning or and even/steady burn rate???? I don't know - it's just supposed to be almost silent.

    As far as the .22lr vs. 5.56 question - I understand your point, but I don't consider them in the same ballpark.

    The thing to keep in mind about suppressors is that they don't eliminate sound, they change the signature of the sound. Also, even if you shoot supersonic bullets, the "crack" sound has no perceptible origin - your target (if it is still alive) can't tell where it came from.
  7. jds324

    jds324 G&G Newbie

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    I guess the sound could be different in commercial loads (not sure of any 7.62x39 subsonic commercial loads, maybe this is a selling point as well) but handloads draw from the same available powders in both sizes, so if they both use the same powder, there can't be that much of a difference if any.

    But it gets better! Now there is also the AAC Blackout which according to the companies website "Full power 123 grain ammunition matches the ballistics of the 7.62x39mm AK". There selling points are that it can be used in AR mags and with standard bolt faces. In all fairness, they also list this AR compatibility as one of their design objectives.

    I think the only difference is marketing, which is a bit disappointing.
  8. jds324

    jds324 G&G Newbie

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    Frago- The ACC Blackout website actually gives the reason why it is better than 7.62x39 and they are all AR specific. It looks like I'll stick with 7.62x39 in the bolt actions.
  9. Johnnycat

    Johnnycat G&G Newbie

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    But then you miss out on buying expensive, proprietary bullets!
  10. Big Cholla

    Big Cholla G&G Newbie

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    jds324: For sometime now, I have been contemplating my next 'hobby shop' gunsmithing project along this same theme. I have both a 7.62x39 AR 15 and a bolt action 7.62x39. I also have been a bullet caster for about 50 years. I see no reason that the 7.62x39 can't be reloaded with a cast 180 to 200 gr. gas check bullet and shot thru either of my rifles. The next step will then be to obtain a licensed sound suppressor and see what I have developed. I have the tools and the skill to thread the end of any rifle barrel. I don't think that the leades of the barrels would have to be lengthened any because the longer bullet can just be seated deeper into the cartridge case. I will be trying to get that bullet moving about 1000 fps at the muzzle, so having the largest case capacity possible is not a consideration. It isn't going to take much powder to move a 180 or 200 gr. bullet at 1000 fps.

    Right now I don't see any major problems in coming up with a viable competitor to the 300 Whisperer with this reloading of the 7.62x39. ...... Big Cholla
  11. cjleete

    cjleete G&G Enthusiast

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    The 7.62x39 is significantly shorter than the 300 whisper, and the parent cartridge, 221 fireball, and the case neck is much longer in relation to the case on the 300 whisper. The cool thing with our AR15's is that we can have them both :)