10.3" vs 11.5" Muzzle Velocity Test

10.3" vs 11.5" Muzzle Velocity Test

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DD MK18 10.3″ complete upper (Black)
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Cloud Defensive LCS picatinny tape switch mount
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10.3″ vs 11.5″ Muzzle Velocity Test


  1. Hung Like Horse on August 19, 2022 at 8:03 pm

    great video

  2. Juanthelawnmowerthief on August 19, 2022 at 8:04 pm

    A few years ago I went with a 12.5 BCM upper because some research showed that it still provided enough velocity to good enough performance from a 556. Curious what the velocity differences would be between the 3 as they seem to be the most popular barrel lengths when it comes to SBR’s.

  3. J on August 19, 2022 at 8:04 pm

    There is a big velocity difference between 14.5 and 16 inch and 16 and 18 inch too

  4. Spushed on August 19, 2022 at 8:04 pm

    Skip to 2:50…ZZZZZZZzzzzzzz Also don’t give a shit what your build is…just post the velocity numbers vs the two barrel lengths.. Curious as to what is up with everyones hard on with 55 and 62 grain as EVERYONE knows that anyone that knows anything you just plink with that shit and you protect with 75/77 grain ammo unless you’re going for armor penetration…

  5. ModernWarflare on August 19, 2022 at 8:05 pm

    Conclusion: 11.5" is the clear winner. Step it up, DD. Spend more time building better rifles and less time spewing anti 2A bullshit.

  6. adjuster56 on August 19, 2022 at 8:08 pm

    Was considering going to 11.5 but after seeing this I will keep my 10.3

  7. josh656 on August 19, 2022 at 8:09 pm

    Love the 11.5

  8. Brian Lewis on August 19, 2022 at 8:11 pm

    Make since you have 40 percent more dwell time in 11.5

  9. venomea on August 19, 2022 at 8:14 pm

    Black hills 50 grain tsx or federal xm556sbct3 would be my choice for 10.5-12 inch barrels the terminal ballistics is the same and won’t make a difference

  10. Keystone Mountain Outdoors on August 19, 2022 at 8:15 pm

    Good video. πŸ‘πŸ»πŸ‘πŸ»πŸ‘πŸ»
    Am kinda looking towards a bcm 11.5” upper as my next buy, debating between the CHF or a enhanced lightweight in the standard rifling with the flutes. The fluted one is about $60 cheeper than the CHF/ BFH. Kinda leaning that route.

  11. George Bigar on August 19, 2022 at 8:15 pm

    Keep in mind m193 stops fragmenting reliably and effectively at around 2600 fps so this changes from a room distance only to a 50 yard gun going from 10.3 to 11.5.

  12. The Third Pin on August 19, 2022 at 8:16 pm

    I just hit like, making it a total of 666 likes. Mwahahaha

  13. LIV2500 on August 19, 2022 at 8:16 pm

    Braced 11.5" barreled ar15 can take a VFG as a firearm because it ought to be over 26" OAL. 10.3" won’t get you there.

  14. Mike on August 19, 2022 at 8:18 pm

    I hear a lot About dwell time and the 10.3 being harsh to shoot due to muzzle blast and flash is it really that bad? For a home defense gun

  15. Myrtle Beach Bassheads on August 19, 2022 at 8:18 pm

    Awesome video

  16. Thomas Jackson on August 19, 2022 at 8:19 pm

    Great info as always. I’ve been sub’d for years but have been watching more and more of your uploads. Could you do a review of some budget optics? Gen 2 Viper, Leupold LR/, Nikon Black FX? I just finished my mk12 and and looking for a new optic. I have a mk4 but it leaves a lot to be desired.

  17. The Jack of All Trades on August 19, 2022 at 8:21 pm

    If you had to choose one for a build which would you choose? A 10.3 or 11.5 bcm?

  18. Austin Irwin on August 19, 2022 at 8:21 pm


  19. Brendan Fazekas on August 19, 2022 at 8:22 pm

    Very cool video great information thanks

  20. βœžοΈŽπ–—π–Žπ–Œπ–Œπ–†π–›π–Šπ–‘π–‘π–Ž on August 19, 2022 at 8:23 pm

    Moral of the story 18".

  21. Tyler Ehrig on August 19, 2022 at 8:25 pm

    So have to ask, have a 11.5 upper I built. Want to do a CQBR Block 3 with a DD 10.3 barrel. In your testing is the DD barrel overgassed? Would you reccomend the 10.3 DD barrel or getting another 11.5?

  22. Anthony's Outdoors on August 19, 2022 at 8:25 pm

    Any body that makes blanket statements about certain cartridges and how much they gain or lose in velocity per inch of barrel are spreading misinformation. The correlation of velocity to barrel length isn’t a linear curve. Not to mention all the other factors that influence muzzle velocity. The only way for you to know is to actually test it. Great video.

  23. Shadetree Armorer on August 19, 2022 at 8:26 pm

    Nice work. I like an 11.5" barrel on a pistol as that combo with a Vltor A5 pistol receiver extension gets you over the 26" needed so you can run a VFG if you want.

  24. Jake M on August 19, 2022 at 8:27 pm

    Now that is one GNARLY friggen bayonet

  25. Mickey Mantel#7 on August 19, 2022 at 8:27 pm

    My girl always said 1" matters πŸ‘πŸ˜‰

  26. Jim Rodriguez on August 19, 2022 at 8:29 pm

    Great comparison..thanks

  27. Cole Dedhand on August 19, 2022 at 8:30 pm

    Yet more scientific proof that water is wet.Β  11.5>10.5.

  28. Uniform Tango 74 on August 19, 2022 at 8:31 pm

    my 11.5" upper is one of my two fav AR SBR upper lengths. The other being my 12" upper.

  29. Observing Humanity on August 19, 2022 at 8:33 pm

    I am viewing this late in the game, but appreciate the information. Especially with just standard every day ammunition.

  30. Hisnameis IAM on August 19, 2022 at 8:34 pm

    2:48 πŸ‘

  31. Chris M on August 19, 2022 at 8:34 pm

    Don’t the SEALs (and other special ops groups) use the 10.3?

  32. Robert Kubrick on August 19, 2022 at 8:35 pm

    I would like to see some M193 nato approximate ammo. I don’t like to spend other peoples money but a couple of boxes probably wouldn’t break the bank vs. channel content.

  33. Albert Ortiz on August 19, 2022 at 8:35 pm

    Wow pretty good jump for 1.2 inches

  34. SM10 on August 19, 2022 at 8:36 pm

    Finally. Awesome video

  35. Justin M. on August 19, 2022 at 8:39 pm

    @Highjak86 You’re the man! I’ve been waiting for someone to do this comparison for quite awhile. I’ve been a hand gun guy for the most part and I’m not too familiar with the performance of rifle ammo.Β Is there any concerns with using this ammo at these speeds?

  36. Idea Called Freedom on August 19, 2022 at 8:39 pm

    Great video, thank you for publishing this data

  37. toprun95 on August 19, 2022 at 8:40 pm

    Great video, nice info

  38. Prairie Patriot on August 19, 2022 at 8:40 pm

    Useful information, thank you. I’d love to see the difference in bullet drop at various distances with both rifles zeroed at the same range.

  39. AlphaRomeo-OneFive on August 19, 2022 at 8:41 pm

    So when she told me my barrel length really does matter, she actually wasn’t lying!

  40. levi conway on August 19, 2022 at 8:42 pm

    What is your twist rate on both barrels? If you have a 1/7 twist rate mil spec barrel you need to use the green tip 62gr or 77gr ammo to get an accurate ballistic test to stay within the military ballistics standards. If you have a 1/9 twist rate commercial barrel then you need to use 55gr to 69gr ammo to get an accurate reading on ballistics. Yes both twist rates can fire any type of ammo but twist rates are in place for certain bullet weights of ammunition. In 1985 the United States military redesign the M16/M4 platform weapon system one of the biggest changes was going to a heavy contour barrel with a 1/7 twist rate. Initially the green tip 62gr bullet was adopted for "compatibility" because the M16A1 a barrel twist rate of 1/12 & for the M16A2 a twist rate of 1/7 knowing that it would take roughly 10 to 20 years to eliminate all M16A1 with the 1/12 twist rate out of military service. I personally witness in 2001 after 911 some Air force Airmen in OEF was issued a M16A1 rifle. It definitely took me by surprised, I thought by now surely to God all M16A1 rifles would of been out of service. I guess you can never say never lol. The original M16 had a 1/14 barrel twist rate. I do believe that they were either destroyed or completely out of service by the end of Vietnam do to the fact that barrel design was only made for a couple of years. The majority of all military personal in Vietnam were issued the upgraded M16A1 by 1965. Hope this information helps.

  41. Universal Law on August 19, 2022 at 8:43 pm

    interesting results I have a 10.5 and thinking about getting 9 in 300 black out.

  42. Eddie DiAndre on August 19, 2022 at 8:44 pm

    I would still prefer the shorter 10.3 over an 11.5. If you want to go shorter than 14.5 I think the 12.5 would be best suited.

  43. spoke1183 on August 19, 2022 at 8:45 pm

    For those that dont know 5.56 rounds reaches min expansion on impact at 2600 fps. Anything bellow that is considered not effective round.

  44. Richard Johnson on August 19, 2022 at 8:46 pm

    Can I ask? Is that a great deal in the big picture of shooting someone or something?

    It is a fact that if you drop a bullet out of your hand, or if you shoot it out of a level gun, both bullets will impact the ground at the exact same time. A bullet has zero flight characteristics. So bullet velocity allows a bullet to travel farther before it hits the ground.

    I am just wondering what the velocity translates to if you are only shooting no more than 200 or 300 yds. If you are shooting a 10.5" or 11.5" barrel, how far were you planning on wanting to shoot? Within 25yds to 50yds, or even up to 100yds. Would it really make a difference?

  45. DKclark329 on August 19, 2022 at 8:48 pm

    Was there any perceptible noise and fireball differences between barrel lengths? I’d love to see a video follow-up on these!

  46. Michael P. on August 19, 2022 at 8:50 pm

    For future reference, as a rule of thumb you want a sample size of >30 to get an accurate and precise average and deviation.

  47. Dylan on August 19, 2022 at 8:53 pm

    How is the ta31 for close up fast shooting?

  48. Hans Shaffer on August 19, 2022 at 8:54 pm

    Thanks for doing this test! I had just ordered a 10.5" barrel, but am now cancellimg it to change to a.11.5". That muzzle velocity gain translates to too big an increase in terminal effectiveness to pass up!

  49. chris j on August 19, 2022 at 8:58 pm

    Exactly the video I wanted. I was hitting steel out to 500 yards with my 11.5 MCX today very faint report but they were hits I was curious about Velocity. Ammo 55 grain Independence XM193

  50. D B on August 19, 2022 at 8:58 pm

    For a minute I thought you had an Omni Blade Bayonet from Mass Effect.