6x45 AR15; thoughts?

Discussion in 'General Firearms Discussion' started by Atomic_Ed, Dec 23, 2015.

  1. Atomic_Ed

    Atomic_Ed Member

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    Anyone familiar with this AR15 build?

    This round appeals to me more so than the 300 blackout. Simpler reloading in that just a neck re-sizing is all that is needed. Other than the barrel, uses .223 parts and magazines. Bullet weights up to 100 gr. can be used.

    With a 90 gr. bullet, holds around 800 ft.-lbs. out to 300 yards compared to about 625 for a 55 gr. .223 bullet at 300 yards.

    Might be a fun round to play with.

    Any feedback?
     
  2. greg_r

    greg_r Lifetime Supporter

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    Had experience with it in a Contender. Good round. The 25x45 Sharps, in my opinion is better. Everything you said about the 6 mm, applies to the 25 caliber also.
     

  3. undeRGRound

    undeRGRound ROLL wif Da MOLE! Supporting Member

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    25x45 Sharps looks to be a winner, maybe even better than
    the highly touted 300BLK! :eek:

    If I get a different AR-15 upper, however, it will be the
    6.5 Grendel which has
    the best terminal ballistics and range in an AR-15 platform ;)
     
  4. 45Man

    45Man Member

  5. MaryB

    MaryB Supporting Member

    6.5 Grendel in the AR-15, almost identical specs to a .308 in the smaller platform.
     
  6. greg_r

    greg_r Lifetime Supporter

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    6.5 Grendel is a good one. Based on a modified 6.5 PPC, which was derived from the 220 Russian. It does require a non-standard bolt in the AR platform though and they are prone to breakage. 6.5 bullets have an excellent BC. But to equal a 308 the Grendel requires a heavy projectile and a long barrel.

    The 6.5 Grindel in the AR Platform handles bullets to around 120 grains, and can not take advantage of the longer 140 grain bullets. It will handle CPX2 game , very similar to the 257 Roberts and the 243 Winchester.

    I became interested in the Grindel when researching for a new chambering for my 6.5 Arisaka rifle. Am interested in the Grendel, but believe if I ever do get around to rechambering the Arisaka, I will go with the 260 Remington, if it will clean up the chamber, which it dosent look like it will. A common rechamber was the 257 Roberts , which uses the longer 7mm Mauser as a parent case. 6.5/06 is doable, but I want to be able to use standard reloading dies.

    Dang you Mole! I had sort of shelved this idea, now you done gone and blowed on the spark, causing it to flair up again!
     
    Last edited: Dec 24, 2015
  7. The 6x45 was real popular around here for AR pistols a few years back. The reason being for use when deer hunting instead of using a shotgun.

    I don't know if it is still the desired chambering or not for this use.
     
  8. undeRGRound

    undeRGRound ROLL wif Da MOLE! Supporting Member

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    MaryB and my son both piqued my interest in the Grendel. I found a
    comparison article that spoke of how the Grendel was an "inferior" 6.5
    but it was comparing it to all the long-action 6.5 rounds that do NOT
    fit into an AR 15 platform. The guys in the comments really gave it to
    the writer, noting how the 6.5 Grendel was superior to ALL the other
    AR 15 offerings in long range terminal ballistics. MaryB and most
    sources I have read say the 6.5G is good to 1200 yards, so I would
    suppose in the hands of an exceptional shooter, one could stretch to
    nearly 1500 yards. That is some flat-out crazy distance! :eek:
     
  9. MaryB

    MaryB Supporting Member

    Actually they have fixed the bolt issues. And it is the same bolt as the 7.62x39.

     
  10. MaryB

    MaryB Supporting Member

    42 inches of drop at 500 yards, basically same as the 308. AT 500 yards the 308 starts to gain in foot pounds of energy delivered though. It is a good trade off for a low cost AR-15 build instead of the way more expensive AR-10 parts. I researched for a long time looking at available configurations that didn't require massive mods to the lower or upper.

     
  11. greg_r

    greg_r Lifetime Supporter

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    I'm not dissing the 6.5 Grendel. I think it's a great round. The PPC rounds based off the 220 Russian have always been super accurate, and as I noted the Grendel is really a modified 6.5 PPC. Add to that the fact that the 6.5's have a very good BC. The Grendel has a good trajectory, but as Mary B points out, it suffers from terminal performance. It's just hampered by the AR platform, but like you say Mole, it's good for what's available in the AR platform!

    The goal of the makers of the Grendel were to produce an effective 800 yards AR. They pretty much did that. But go to any long range match and look at the Grendel chambered AR's, you will find 24 to 28 inch barrels and billet receivers. If I were to build a Grendel upper, I would use a 22 or 24 inch barrel. Would make a good beanfield rifle. (FWIW, my beanfield rifle is a 26" 280 Remington.)

    The bolts for the 7.62x39 based AR's have improved. They used to be made out of 8620, now they are made out of 9310, but they still break. At the lugs around the extractor cut. That's the reason, IMHO, that the 6.8 superseded the 6.5. You don't hear much about 6.8 bolts breaking. The 6.5 Grendel, again IMHO, is the better round.

    To be fair, the bolt is a known weak point in the AR platform. 5.56 bolts break, bottom line. Most people just don't shoot them enough to break them. The life of a 5.56 bolt is 6000 rounds. Sometime after that 6000 rounds, the 5.56 bolt will break. (Not to imply that they can't break sooner.)
     
    Last edited: Dec 25, 2015
  12. Atomic_Ed

    Atomic_Ed Member

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    Thanks for all of the input everyone!

    I was thinking of a round that would allow the use of the standard bolt and mags when I was looking at the 6x45. A simple neck re-sizing was also appealing. Now that the 25x45 sharps was brought to my attention, I may drift in that direction.

    I've shot a 6.5 Grendel and it was very impressive. Gophers at 300 yards was a piece of cake. But now you're into a different bolt and brass. It seems to me it so close to a .308, you might as well pull out the .308 and be done with it.

    The 25x45 or 6x45 appeals to me as an "in between" round easily adapted to the AR platform. The 300 blackout is still on my list due to its increasing popularity, but the other two cartridges peak my personal interest more.
     
    Last edited: Dec 27, 2015
  13. MaryB

    MaryB Supporting Member

    .308 puts you into AR-10 hardware and a higher price tag... 6.5 Grendel VS Elk

    [ame]https://www.youtube.com/watch?v=FN_DGVrlfzc[/ame]
     
  14. greg_r

    greg_r Lifetime Supporter

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  15. MaryB

    MaryB Supporting Member

    Barrels are available in a lot of lengths. I went 18" for ease of use in the woods up north where I deer hunt with my brother in law. It doesn't give up much velocity and is accurate.