Return to 6" 300 BLACKOUT AR-15 BARRELED UPPER - MAS DEFENSE RIDGELINE 7.25" M-LOK RAIL

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0 of 0 people found the following review helpful:

Exceeded my expectations November 4, 2023 : Steven J Martinez from Cheyenne, WY United States   I already have their 16-inch 300 blackout upper, and I decided to get a 6-inch just for the heck of it, and man, was I surprised how well this thing performed. Much more accurate than I expected a 6-inch barreled upper to be. The quick shipping was nice, and the price is always great with this company, especially for the quality of fit and finish for their products. Was this review helpful to you?

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Really nice build May 6, 2022 : Joe from , IL United States   Hand guard is what sells this great contour for your hand to have a natural shelf. Really makes for a solid tub or tob grip. Was this review helpful to you?

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Top notch quality! April 30, 2022 : Roger Workman from Mint hill , NC United States   Could not be more satisfied with their craftsmanship and their attention to detail! Was this review helpful to you?

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Lets Go Brandon November 11, 2021 : Justin Jones from McDonough, GA United States   Once again another amazing product from these guys at an even better price. Quality is top notch and functionality is always 100% Was this review helpful to you?

1 of 1 people found the following review helpful:

Quality&affordable May 17, 2021 : Jacob from Midlothian, VA United States   Got the bcg and charging handle to go with it. Looks really slick. Came in perfect no blems. Everything torqued to spec. Gonna be interested to see if itll run some 220 grain subsonic without messing with my buffer. Running standard h2 right now. Just going to be checking reliability for heavier loads because i do want to shoot subs suppressed and unsuppressed. If you are tired of psa and the normal companies. Definitely ORDER FROM HERE!!!!!!!! Update 5/16/21 doesnt cycle subsonic. Anything over 160 grain is a no go. ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- MAS Defense Reply: Jacob, I would try using a standard 3oz carbine buffer or a custom lighter weight one. That should work when firing suppressed. If it does not, you may have to open the gas port in the barrel little by little. The problem is 300 BLK needs 9" of barrel length to complete the entire burn. Reducing the barrel by 1/3 creates less back pressure which is used to move the BCG and buffer. A larger gas port will allow more gas to flow through the gas system to move the components. If you switch to firing supers again you can swap the buffer to a H1 or H2 to absorb the additional back pressure. Thank you for your business and your feedback! Was this review helpful to you?

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Excellent! April 5, 2021 : John Matteson from Neillsville, WI United States   From ease of use on the website to outstanding customer service and fast service, you provided a five star experience for sure! Was this review helpful to you?

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Great February 26, 2021 : Dallas Shuemaker from Valley View, TX United States   I love the upper it looks great and feels great I also like how when MAS saw two different addresses they made sure that it was the right person and that made me feel more comfortable with always being a return customer also didn't take long to receive my badass new upper Was this review helpful to you?

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6" 300 blackout upper reciever February 26, 2021 : Justin Morton from Detroit , MI United States   Most builders praise aero precision. I always have told people that Mas Defense makes a far superior product line. They are more durable,  looks far better than any other upper reciever on the market, the price is always above reasonable and they ship faster than any other company.  In my opinion this reciever is the best one I've purchased so far.  I highly recommend this company to a friend and this 6 in 300blk is a must have. Was this review helpful to you?