We at TFB have been excited about the MDP-9 ever since Angstadt Arms set the hype train rolling with a promo video promising a new pistol calibre carbine. That gun, the MDP-9, was officially announced just before SHOT Show so it was great to get hands on with the gun and put a few rounds through it.

The main feature of the MDP-9 is its roller-delayed blowback action, borrowed from and inspired by the iconic submachine gun – Heckler & Koch’s venerable MP5. Can the MDP-9 steal the MP5’s crown? Well a roller-delayed blowback gun with AR controls and parts compatability is certainly a winning combination.

The MDP-9(Matthew Moss/TFB)

The development of the gun was driven by Angstadt’s experience in the US Army’s Subcompact Weapon program, which sought a new submachine gun for some niche roles such a close protection. For those sorts of roles a compact package is needed and with conventional, straight blowback AR-9s, that means shortening the barrel and sacrificing accuracy and velocity. The MDP-9 addresses this and has an overall length of just 14 inches with the stock or brace folded.

The MDP-9 in braceless pistol configuration (Matthew Moss/TFB)

With no need for a buffer tube there is less mass at the rear and as a side effect the recoil impulse is less spongy. A pair of rollers in the bolt slow the opening of the action once the gun has fired and allows pressures in the barrel to drop to safe levels before the gun cycles open. Shooting the MDP-9 is a very pleasant experience with rapid follow-up shots made easy, this controllability is magnified in the non-civilian full-auto variants of the gun.

The MDP-9’s charging handle (Matthew Moss/TFB)

The MDP-9 has a full-length 12 o’clock picatinny rail, an MLOK forend but until other AR-9s its non-reciprocating charging handle is, like an MP5, located forward in the handguard. Unlike the MP5, however, the charging handle can be switched from left to right as needed. The guns feed from Glock magazines and weigh just over 3.5 lbs unloaded and have 5.85″ barrels with fluted chambers to aid extraction.

The MDP-9 (Matthew Moss/TFB)

While the Angstadt uses a bolt with rollers it is much simpler to machine than the MP5’s with a more rectangular profile but retaining the pair of opposed rollers in the bolt head. The example we got to take a look at on Range Day at SHOT 2020 is not finished with the black nitride finish that production guns will have.

A look at the MDP-9s bolt, production guns will have black nitride coated bolts (Matthew Moss/TFB)

The MDP-9 will be now available as a pistol, with braces available and able to be mounted on a picatinny rail at the rear. The MDP-9 is also going to be offered as a stand-alone upper assembly which will work with both the earlier UDP-9 and other AR-9s.

A closer look at the MDP-9s bolt and rollers (Matthew Moss/TFB)

Don’t forget to check out TFBtv’s video, with none other than Richard Angstadt explaining the features to James Reeves:

Find out more at Angstadtarms.com.