GUN Buying a CMMG upper – questions on the front sight post/gas block, et al

Discussion in 'On Topic' started by Ebtromba, Feb 10, 2009.

  1. Ebtromba

    Ebtromba Active Member

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    I am in the process of putting together a CMMG compete upper via its website - http://cmmginc.secure-mall.com/shop/?cart=1504960&cat=27&

    The purpose of this rifle will be general plinking out to 100-200 yards, nothing too hardcore. I do want it to be as accurate as can be, within my budget. I will be putting some very decent optics on it. Think accupoint.

    1. I will be going with a 20” barrel, the ones at the very bottom of the page linked above. What is the difference between the MedCon and the Government uppers? Any reason to choose one over the other?
    2. These 20” CMMGs obviously use a rifle-length gas system, correct?
    3. My main noob question: I do not want or need a front sight, or the post, or anything. There is no option for “no front sight” or “no front sight post”. If I leave the sight post option as A2 post, and then choose under Front Sight Base/Gas Black Option the YHM 4 rail gas block, or the Micro Gas block, for example, the rifle will not come with a front sight, correct? I would assume so, but leaving the sight post option as A2 post makes me freaking nervous.


    Many thanks.
     
    Last edited: Feb 10, 2009
  2. GarandBobcat

    GarandBobcat New Member

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    Government profile barrel tapers down to a lightweight under the handguards, thenthickens up at the front sight base and stays that way all the way out to the muzzle. MedCon, in CMMG lexicon, is almost a heavy profile--the thickness you see between the FSB and the muzzle is how it is all the way back to the chamber, instead of being thinner and lighter under the handguards. MedCon is a little heavier, but probably better if you're going for a DMR-type rifle or something to that effect, otherwise I'd say stick to the government profile.

    Yes, a 20" upper will use a rifle-length gas system.

    If you get the micro gas block or something similar, it'll come with that instead of the standard FSB. If you're really nervous about it (I wish their site updated as you chose options, so that only applicable choices are shown, but oh well), call them or email them and make sure. They're supposedly reasonably friendly, and they were relatively prompt in responding to a trivial email I sent them a month or so ago, right when the election buying craze was just starting.

    Good luck and enjoy the upper, when you get it.
     
  3. Ebtromba

    Ebtromba Active Member

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  4. If you choose something that's not a standard gas block/ front sight just leave the front sight post set to A2. They'll know what you mean.
     
  5. Ebtromba

    Ebtromba Active Member

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    Wirelessly posted via wap.offtopic.com (Opera/9.51 Beta (Microsoft Windows; PPC; Opera Mobi/2723; U; en))

    yeah, i figured. i just didn't want anything stupid like that to go wrong
     
  6. Paul Revere

    Paul Revere OT Supporter

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    panzerace has the 20" medcon and i believe he likes it. for all intents and purposes it's the same profile as a colt hbar
     
  7. Ebtromba

    Ebtromba Active Member

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    pimp. I think I'm going to go with the YHM single rail gas block, in case I ever want to open-sight it in the future. same price as the micro gas block.

    and let the waiting begin

    dude on sig forum said he ordered about the same thing as I'm getting back in december. great.
     
  8. fatmoocow

    fatmoocow bored OT Supporter

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    Any reason for 20" ? Just so you know, 20" isn't going to be any more accurate than the others, just slightly higher velocity. for <200 yards plinking I'd go with light and short.
     

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