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10.3” vs 11.5” AR barrel long range comparison

Mountains, Mullets, Merica!

88,373 views

Curious how a 10.3" 5.56 AR barrel performs at distance vs an 11.5" barrel? Tune into this video for a look at a real world side by side comparison of these popular short barrels out to 820 yards. We also have some new NAS3 high pressure ammo provided by Phantom Defense that we will work into testing to see how the increased pressure/ velocity will change the performance of barrel length.

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Ammo
IMI MK262 5.56 nato 77gr smk
Phantom defense NAS3 77gr Hornady otm
Phantom defense NAS3 69gr TMK

10.3" rifle details
LMT Defender 2000 lower
Geissele SSA trigger
Magpul MOE PR stock
Daniel Defense Mk18 upper
Centurion medium weight chrome lined barrel- 1/7" twist
Surefire FA556 suppressor
Athlon 1-10 LPVO
Pods knobs by PR shooting solutions

11.5" Rifle details
KAC SR15 lower
Griffin armament 11.5" Mk2 upper- 1/7" twist barrel
Griffin armament 762 HRT suppressor
Griffin armament 1-10 Mil-R SFP scope
Griffin armament single piece mount

00:00 Opening & video flow
01:53 10.3" MK13 details
03:40 11.5" Griffin Mk2 details
05:04 Ammo details
06:35 Testing hypothesis
07:21 Call to action- subscribe
08::00 100 yd performance
15:40 10.3" Mk18 415 yds - mk262
17:16 11.5" Griffin 415 yds - mk262
18:18 10.3" Mk18 650 yds- mk262 vs phantom
21:39 11.5" Griffin 650 yds- mk262 vs phantom
25:02 10.3" Mk18 820 yds
27:54 11.5" Griffin 820 yds
31:37 Shooting performance review
37:24 ejection pattern, pressure & cycling
38:22 closing comments

20 Comments

@blahblahblah7554 1 year ago

This dude has answered every question I came up with

@willbarnes9121 1 year ago

Most informative page on everything you’re using in the description section. That makes huge difference and make the video so much better.

@lancecockerell4345 1 year ago

You have saved me countless hours and money with these videos. By far my favorite creator. Your like a free college education without the tuition for anything shooting.

@sammy080798 11 months ago (edited)

A friend gave me a 10.5 K&M tactical upper. He said it shot very badly. So I slapped it onto my pistol lower and took it to the range. He was right, 4 to 5 moa at 100 yards. I bought and installed a Rainier select 10.5 barrel and put a NiBo BCG in it. Took it back out and with a 1-4x LPVO, 77gr otm and an OCL polonium, brought it down to 1.25 moa at 100 yards. This is now my favorite 556 gun

@jrbrown1988 1 year ago

Please do 12.5in, would love a comparison from you

@tjwest13 1 year ago

Don’t understand how we’re not past 500k subscribers. Side note, think it would be cool to see some combat accuracy tests like 9 hold reviews, but with your flair on it it. Keep up the good work!

@grzegorzp.5734 1 year ago

I don't need longer barrel! I don't need higher pressure ammo!
ALL I need is YOUR SKILLS :)
Fabulous video!

@mountedpatrolman 1 year ago

Congrats on the Gundie. I carry a Mk18 at work, and also have a 11.5 URGI, so this was a very interesting video. It would have been cool if you could have done some sort of terminal wounding performance out there at 820.

@jasonnoble2194 1 year ago

Most of the videos Ive watched on 5.56 barrel length all showed the biggest jump in fps was when you went from 10.5 to 11.5. From there the jumps werent as big. So your findings sound right to me

@wadf29 3 days ago

This video breakdown is just fantastic. Thank you!

@billydanzz 1 year ago (edited)

12.5 it is then!!!
It would be a cool video to show the set-up and how to use the gadgets, scope levels, target hit flashers, etc.

@justinblower7598 1 year ago

The entire internet should be subscribed to your channel

@angeleyes4039 1 year ago

From the frozen tundra of Idaho!!! Giving my beloved mk18 a workout past 500 but it is really satisfying to get hits at 700-800. Thanks for braving the cold for this video!

@J.D.Grenadier 1 year ago

Am I the only one that feels like I need a lot more training after watching these outstanding videos? Man, you are steady on that trigger!

@TheGearLord 1 year ago

If there was ever a channel that deserved about a million more followers than what it has, it would have to be this one. Awesome video!

@Greaner762 1 year ago

I’ve watched a ton of shooting content on here and this is by far my new favorite channel. You’re like a younger, more tech savvy Paul Harrell

@itouchipods 1 month ago

Best video I've ever seen in my entire life. You've earned yourself a sub, sir.

@thecoolestkeith 7 months ago

This was cool to see the capabilities of these shorter systems!

@MadCow-mb3fw 1 year ago

100k by the end of the year? Man I think you'll have that by May

@Vince-Metzger 1 year ago

Your work creating these videos is impressive. I like how you pose a hypothesis and then thoroughly investigate it quantitatively. You earned another sub!