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Maxim Defense Industries MDX 505 PDX/SCW Compatible URG Upper Receiver
$1,295.00 $1,165.50 Save 10%
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Most Helpful Positive Review The best purchase I've made in a long time!
This is the second one I've bought this month so that says something! These little guys are for sure worth every penny! Great fitment, great looks and great price! I cant wait to get my hands on the 3000 Blackout when it comes available!
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AR project

by Hugi, Verified Owner from TX, United States Written on June 13, 2025
I have always look and admire Maxim defense for suck good function designs and now I building my own. And also aptics planet for the awesome deals
Pros:
  • +++++++++
Cons:
  • None
Best Used for:
  • Best Any project
Would recommend: Yes
Was it helpful to you? Yes | No

Maxim PDX 556 Upper Black

by Roger, from FL, United States Written on March 30, 2022
Great system. I love the fact that this Maxim PDX upper works with my non-PDW equipped AR lowers. Something my Q Honey Badger upper can never do. It’s nicely universal in that respect. The upper functions smoothly suppressed and un suppressed. Cycling is more violent obviously with my silencer attached but without the can rounds eject perfectly at 3 O’clock. If you’re in the market for a pint sized barrel with a raised 416 style upper this is what you should grab before they’re all gone.
Pros:
  • Small
  • Strong
Cons:
  • None
Best Used for:
  • Backpack setups
Would recommend: Yes
1 of 1 found the following review helpful.
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Maxim PDX Upper

by Chris, from GA, United States Written on April 26, 2021
The 300 blackout version functions great! Eats subsonic and supers with no issue, or modification, it just works. Got a Eotech zeroed to 25, it is spot on. The handguard didn’t heat up as I anticipated, but could if you run a bunch of mags back to back. It is a nice and small package, perfect as a truck gun.
Would recommend: Yes
1 of 1 found the following review helpful.
Was it helpful to you? Yes | No
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