6.5 Grendel AR-15 vs 7.62 NATO AR-10/SR25/GII/...

Discussion in 'AR15/10 Rifles' started by bruce_ventura, May 11, 2015.

  1. bruce_ventura

    bruce_ventura Well-Known Member

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    This question goes out to folks who have owned and shot both types of rifles.

    I have a project coming up where I need a semi-auto rifle with low dispersion (<.75 MOA for a 5-shot group at 100 yds). I need the ballistics of the 7.62 NATO M118-LR cartridge, and a max range of at least 1,000 yds at sea level. I have multiple AR-15 rifles, but no AR-10/SR25/GII/... rifles.

    I started to look at rifle prices and asked myself if I could get the same drop and wind drift in an AR-15 platform. I was a bit surprised to see that the 6.5 Grendel with a 123 gr Scenar has nearly the same ballistics (not including bullet energy) as the 7.62 NATO 175 gr M118-LR round. It's really wind drift that I'm trying to match, not bullet drop. I could save more than a few bucks by buying or building a 6.5 Grendel upper for this project instead of buying a new 7.62 NATO rifle.

    My question is, am I missing something here? Is there a good reason, either for ballistics or rifle function, reliability, accuracy, etc., to use an AR-10/SR25/GII/... rifle instead of a. 6.5 Grendel? Again bullet energy is not an issue - I am essentially punching paper in this project.
     
  2. MainDish

    MainDish Well-Known Member

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    Just for entertainment, I'm going to try and see how many 308 defenders are awake!

    I don't really understand the 308 for non-military applications. If cheap brass but a decent-sized cartridge is desired, one can neck down NATO brass into 7mm-08, which is like the 308's younger, better-looking, stronger brother. Seriously, the ballistics of the 308 don't hold up in my book, and a 160gr 7mm bullet can really do some great damage even at 08 speeds.

    Short answer to your question, I think the Grendel is a fine choice. I built one because it does outshoot the 308 in a lighter platform. I love my 7mm-08 but the reports on the 6.5 bullets are that they punch above their weight in terminal performance. An antelope trip with both this fall will hopefully prove something useful.

    Once you buy the brass, the Grendel doesn't cost more than anything else with a similar bullet weight. In fact you'll save 50% on powder.
    Some argue that the special bolts and mags are a deterrent. $150 bucks gets you a Alexander Arms "hard-use" bolt and 4 mags, which, if we are honest, is an amount of money we tend to burn rather quickly in this sport on less important things.

    My $.02. Bring on the 308 lovers!
     
  3. Win.308Stealth

    Win.308Stealth Well-Known Member

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    I own a Grendel AR, AR10 in .308, and a Mauser based target rifle in .260 Remington. Paper punching I would go with the Grendel. But don't overlook the .260 Remington in the AR10 platform.
     
  4. scrmblr1982cj8

    scrmblr1982cj8 Well-Known Member

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    Ok. I'll bite on this.

    Before I got into reloading, I was not very excited about getting away from standard calibers. I live in a small town in SC. With the place I can hunt, about 375 yards is the farthest shot I would ever take. Around here, you can easily find .308/7.62, .30-06, .300WM, and 7mm. After that, it gets harder to find things. Not all stores carry 7mm-08 or .25-06. It was only last year when Academy Sports came to town that I saw my first box of 6.5 Grendel. What I like about the .308 is (1) I can easily find ammo in town without having to order it online or drive to a different county to get it (2) there is a wealth of information on reloading for the caliber, and (3) I haven't had any issues getting reloading supplies for it.

    If ammo selection for the 6.5 Grendel was better around here, or if I saw bags of brass at the local reloading store, I'd be more excited about the round. Now that I have started reloading, I could order the brass and bullets, but since my potential shots aren't that far, the .308 works just fine for me for now. If I ever move, that may change, but I'll stick with the .308 for now.
    I think the 6.5 Grendel has great ballistics, but
     
  5. MainDish

    MainDish Well-Known Member

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    I completely understand and agree with using common calibers if that is a priority. Personally I hoard the powder, bullets, and brass that I use, so I don't worry too much about availability. Besides that, most of the less common calibers are modifications someone made from something existing. It stands to reason that they are then an improvement in one way or another, depending on your application. The improvements are usually minuscule, but it makes for good arguments.
     
  6. scrmblr1982cj8

    scrmblr1982cj8 Well-Known Member

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    I wouldn't call it a priority, but it does make it easier. I just picked up a 6.5x284. Definitely can't wait to start shooting it. I'm going to have to drive 75 miles to find brass for it if I can find it. I'm much more willing to get more "exotic" caliber now that I can make it myself.
     
    Last edited: May 13, 2015
  7. MainDish

    MainDish Well-Known Member

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    I'm fortunate to live near a very well stocked reloading shop. I didn't realize it until I started spending time on the forums. For example, they have 3 brands of 6.5-284 brass:
    6.5MMX284 Win. (100) - Gunstop Reloading Supplies
    They have a pretty good mail order business - if you sign up for their email flyer you can usually save 5-10%.

    I still get lots of my stuff online though.
     
  8. scrmblr1982cj8

    scrmblr1982cj8 Well-Known Member

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    The local Ace Hardware is the best place around here to get reloading supplies. The only new brass they carry is .270, .243, and 7mm. Of those, I only have a few 7's. Otherwise, it's 90 miles to the Sportsman's Warehouse in Columbia or 80 miles to Myrtle Beach. Brass supplies in both places has stunk the last few years.

    Anymore, I order online. Much less frustration!
     
    Last edited: May 13, 2015
  9. 65 GRENDEL

    65 GRENDEL Well-Known Member

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    I shoot both the Grendel and the .308. I use them both for paper punching out to about 600 yards But both platforms are good out to 1 k with proper glass.
    My best long range deer kill for both is 425-450 Yards, you'll be happy with either or both. My vote is for both.
     
  10. budlight

    budlight Well-Known Member

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    For years in the military I used the M-14 and m-60. both wonderful, but the problem is weight of the rounds and weapon.

    The grendal is about half way in between the 223 and 308. Being able to use the ar15 platform is a plus. We have shooting areas in the local hills and I have lately picked up hundred's of 6.5 grendal brass. So the popularity must have gone up


    6.5 Grendel
     
  11. 65 GRENDEL

    65 GRENDEL Well-Known Member

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    The ammo is much lighter then the .308, especially if you're carrying 2-300 rounds in magazines.