300 Blackout in 10.5" pistol

mzvarner

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Mar 7, 2013
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Impatiently awaiting the delivery of my 10.5" 300 BO pistol. I reload for everything I shoot, excluding 22LR. Wondering what you guys are finding as a pet load. I plan on using this as a plinker and maybe short range hunter. I do not have a suppressor yet, so not sure how big a deal the subs are...
 

spife7980

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Without a can the subs are still louder than hell. For that reason I would go for the 125 gr bullets because setting it up for subsonic is just a losing proposition in every way other than being silenced.
 

padom

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  • Mar 13, 2013
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    125 SMK and 125 TMK with CCI 450's and H110 is the most accurate 300blk super combo Ive tested. I also tested 3 different 300blk 10.5" barrels. Almost gave up on the 300blk experiment with accuracy in the 1.25-1.5" area from the first two barrels then got this 10.5" Rainier Ultramatch and wow what a tack driver. I shoot this out to 500yds with a Leupold 1.5-5 MR/T with boring consistency. This thing is one of my favorite AR's by far.

    10.5" Rainier Ultramatch 300blk 1:7.5 (Shilen Blank) Pistol Gas
    Aero Precision Upper Receiver
    Aero Precision SBR Lower Receiver
    Daniel Defense MFR 9" M-LOK Handguard
    Rugged Suppressors QD Flash Hider
    Rugged Surge 7.62
    Strike Industries Charging Handle
    FailZero NiB BCG
    Hogue Grip
    Seekins Ambi Safety
    Magpul BAD Lever
    Geissele SD3G
    Spikes Heavy Buffer
    SLR Sentry 7 AGB
    Melonite Pistol Gas Tube
    Magpul CTR
    ADM AD-Recon 20moa QD Mount
    Leupold 1.5-5x20 MR/T CM-R2
    StreamLight TLR-2 High Lumen 800 Lumens w/Green Laser



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    [IMG2=JSON]{"data-align":"none","data-size":"full","src":"https:\/\/i.imgur.com\/igw5Vje.jpg"}[/IMG2]



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    Last edited:

    mzvarner

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    padom, holly shit thats some crazy accuracy!and from a pistol with a 1-5 none the less! I was only expecting minute of paper plate at best but now...

    125 SMK and 125 TMK with CCI 450's and H110 is the most accurate 300blk super combo Ive tested. I also tested 3 different 300blk 10.5" barrels. Almost gave up on the 300blk experiment with accuracy in the 1.25-1.5" area from the first two barrels then got this 10.5" Rainier Ultramatch and wow what a tack driver. I shoot this out to 500yds with a Leupold 1.5-5 MR/T with boring consistency. This thing is one of my favorite AR's by far.


    J2j8wCp.jpg

     

    padom

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  • Mar 13, 2013
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    That target was shot with my Vortez Razor HD back when I was doing load development. I regularly shoot the 1.5-5x20 to 500yds though on steel. Its all in the barrel. I have multiple friends that have many 300blk AR's and have been shooting 300blk for years. They all said 300blk was just a fun range toy and it wasnt accurate. Thats what got me into 300blk. I set out to prove my friends wrong and build a 300blk that was extremely accurate and capable of headshots out to 100yds.

    First 2 barrels I was starting to believe them that 300blk wasnt an accurate cartridge and almost gave up. They both shot 1.25-1.50" MOA at 100yds with maybe a rare 1moa group. Third barrel was a game changer and its my favorite AR. I have both Pistol and SBR lowers that I swap this 300blk and my 10.5" WOA 5.56 upper between them.

    The DD MFR handguards are also one of my favorites. The way they install makes them rock solid and love the feel of the handguard in my hand. I have another one in the box Im going to use for a 12.5" Douglass 5.56 upper build.
     
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    mzvarner

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    ok that makes a little more since, but it is still impressive shooting. I have a Radical Firearms pistol coming tomorrow. I have not found many reviews on accuracy, ultimately just that people are happy with the guns and they function as expected.

    What other combinations did you test? I have a box of 500 150gr palma match and a few 178 Amax that I was planning to shoot in my rem 700 when the 6.5CM barrel dies, but I had a day shooting in 17-22 MPH winds that has me thinking I am not leaving 6.5 now.