5.56 vs 6.5 Grendel, velocity, and energy debate!

I really did not venture out much from the 5.56 and x51 until I went and bought an AAC 300 BO upper, it was a blk friday super sale, could not pass up their complete upper at that price. I love the BO and have built several now of varying lengths. Not sure what I do not have covered with those (3) calibers…running the 200-220 gr subs is just good clean fun.

Along comes this new 6.5 MPC and I’ve got caliber acronym burn out, of which is which.

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Hard to keep up, and I want them all.

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I’m a huge fan of the .224 Valkyrie, but, I’ll leave this video here for your consumption. One of my dreams is to have a few complete uppers of a few different cartridges on hand. :cowboy_hat_face:

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That’s what I really like about the AR platform. You can run just about anything from .17 to .50bmg. I’ve seen .410 shotgun uppers as well as crossbow. For the most part, no real modification is needed other than the .17 and bmg, both use different hammers and spring.

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Indeed. I was able to try a converted .22 LR on a guy’s M&P Sport II at the range last week. I was a blast! Pun intended. The only “recoil” was with the bolt. Haha. I kinda want to build a cheap .22 LR plinker AR out of an Anderson lower and BCA upper.

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I have one of those conversion kits. Swap out the BCG and use the mag that came with it

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Yup. It was a CMMG kit he bought for like $200.

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The kit is IMO, over priced. But, it’s nice to use a good quality AR while shooting low cost .22lr It’s still less than a whole weapon though.

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I don’t claim to be an expert and I have very little experience with 6.5 Grendel and .224 Valkyrie, but I have noticed some things in comments that I don’t quite agree with. Below are some generalizations based on the majority of rounds per caliber from what I have seen.

5.56/.223
-fast muzzle velocity
-poor ballistic coefficient bullets
-good energy out to 200 yards with best bullets, 100 yards with most bullets
-easily affected by wind drift
-flat shooting to medium range (500 yards approx. compared to other cartridges)
-bullets have poor sectional density

5.56/.223 is a great plinking round, inexpensive and plentiful. Its short and light bullets don’t do it any favors at distance with wind, energy, and bullet drop; but its velocity makes up for this in the short to medium ranges. Though hunting bullets are designed for the caliber to even take deer, the low energy and poor sectional densities of most bullets make this caliber more suitable for varmints. Lowest recoil out of all the rounds talked about.

.224 Valkyrie Starts out fast, good ballistic coefficient bullets,
-fast muzzle velocity
-good ballistic coefficient bullets
-good energy out to 300 yards with best bullets, 200 yards with most bullets
-less affected by wind drift
-flat shooting to extreme long ranges (1000 yards approx. compared to other cartridges)
-bullets have okay sectional density

.224 Valkyrie is a great long range round for target shooting. Its long slim bullets are less affected by wind, shoot flat, and hold energy better than its stubby .223 cousin. Though it appears to have decent energy at close range with okay sectional density needed to get penetration on deer sized game, I have not seen any loads made for deer hunting and the .22 caliber bullets don’t do it any favors in this hunting category. This is meant to be a fast round and so it benefits from long barrels to get it that velocity. The perfect varmint caliber and fun long range gong ringer.

6.5 Grendel
-medium muzzle velocity
-good ballistic coefficient bullets
-good energy out to 400 yards
-less affected by wind drift
-flat shooting to long ranges (800 yards approx. compared to other cartridges)
-bullets have good sectional density

6.5 Grendel is a good long range round. Though its velocity is not impressive, the good ballistic coefficient bullets are less affected by wind, hold energy very well, and shoots pretty flat for a medium velocity round. The good energy at distance and good sectional density make the Grendel the best deer size hunting caliber in the AR-15 platform, yet it feels at home hitting steel even out to 1000 yards or hunting varmints. Most people believe the Grendel needs a long barrel, but this is not the case. It is not a caliber that needs those high 3000 fps velocities to do its thing, so doesn’t loose much in barrels 16 inches or shorter, that’s why you have been seeing them more often. A bit more recoil but this is your do it all AR-15 round if you ask me.

.300 Blackout
-slow muzzle velocity
-okay ballistic coefficient bullets
-good energy out to 200 yards with best bullets, 100 yards with most bullets
-easily affected by wind drift
-flat shooting to close ranges (300 yards approx. compared to other cartridges)
-bullets have okay sectional density

.300 Blackout I am not afraid to say I have fallen in love with. Reasonable priced ammo that is easy to find and a whole lot of fun. It shines with what it was made to do, fire subsonic suppressed rounds or supersonic rounds for a little more of a bang. It is a slow round, but doesn’t need those super long barrels. It feels right at home in a 7" to 12.5" barrel. Sure it doesn’t shoot flat, and the fat bullets are more easily affected by long slim ones, but I guarantee that if you have it properly zeroed, you can hit a man size target from 0 to 300 yards with the same point of aim. Though there isn’t a whole lot of energy behind it, it has a .30 cal bullet for larger wound channel with okay sectional density, and really very comparable to .30-30 before Hornady’s LeveRevolution came out. With the best hunting bullets, I wouldn’t hesitate to take a shot at a deer between 100 and 200 yards. Added benefits, reload from .223 brass and 30 rounds in a standard 30 round AR-15 mag.

Sorry for the long post, just my take on the 4 calibers others have mentioned. Hope it gets people thinking. And hey, if you can have 1 caliber, why not have all 4. :wink:

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300BO FTW

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Well, even though the PSA kit is now $480 you got me thinking…where is the ammo .26 a round?

Disregard, I found the Wolff…

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I really like your zombie rig, you build it?

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Yes Sir, about 2k right there.

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This might sound immature but that 300 bo with the drum kind of looks like a penis. It still looks cool but in a Spikes tactical dueling penises kind of way :rofl:

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Well,

if thats the case then this is a raging fill in blank

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220gr Viagra, down range…

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I get around all this debate by having one of each

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I need that muzzle brake, give it to me now.

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Very good write up Brother!

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http://ordainedarms.com/store/product4.html

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