The submachine gun’s (SMG) most prominent role, indeed its raison d’être stretching back to the World War I trenches, is as a CQB weapon. Ease of sound suppression is another important SMG advantage that has come to the forefront. Increases in terrorism, organized crime, and drug smuggling has created a new need for the SMG. The “new” LWRC SMG 45 from LWRC International reasserts the SMG’s potency and viability in the modern world.

LWRC SMG 45 Operation

The SMG 45 was a much heralded introduction at the 2015 SHOT Show. It took on unicorn status for the last four years; much talked about with reports of sightings, but nothing solid appearing on dealers’ shelves. This started to change in mid-2019 with LE/military-only select versions becoming available, as well as braced pistol semi-autos for civilians evaluated herein.

LWRC’s goal with the SMG 45 was to provide an updated replacement for aging submachine guns found worldwide. The SMG 45 operates via an inertia-driven, delayed blow-back design. Instead of a roller-delayed system found in Heckler & Koch’s genre-defining MP5 or the direct blow-back design found in many other submachine guns, the SMG 45 uses what LWRC describes as a short-recoil action that includes a moving barrel.

During firing and the initial steps in the cycle of operation, a locking collar links the barrel and bolt. This creates a larger mass to better absorb recoil and slow the bolt when it begins to move. As the bolt and barrel travel rearward under recoil, the locking collar engages the top of the feed ramp and is pulled downward, decoupling the bolt from the barrel. At this point, the barrel stops after moving about a quarter inch, but the bolt continues rearward, extracting the spent case and performing the remaining steps in the cycle of operation.

Linking the bolt and barrel together during the initial portion of travel slows the bolt and allows time for the chamber pressure to peak and start to drop. This allows for a much lighter bolt assembly, especially when compared to the beefy blocks of metal associated with blowback operating SMGs. The lower mass results in less felt recoil and reduced sight movement during operation compared to most SMGs including both contemporary and legacy designs.

Controls and More

SMG 45 operating controls and basic ergonomics are similar to the ever so prevalent AR; this is an important consideration for training/orientation purposes. Ambidextrous safety and bolt levers are LWRC standards. An M4 flat top-like upper allows for flexibility in optic choices. AR height mounts work best. LWRC includes flip up/down Magpul MBUS Pro Sights. There is a centrally located paddle style magazine release found in front of the trigger guard. LWRCI also uses an AR type fire control system.

A non-reciprocating charging handle is located on the left side of the forend. LWRC covered its user-configurable forend rail system and strategically placed Picatinny segments by rail panels with a hand stop on the bottom near the barrel. Premium hard coat anodized nitride nickel boron surface treatments are found on the bolt group and other strategically important areas. The SMG 45’s 8.5-inch cold hammer-forged chromoly steel barrel gives overall length of 26 inches; that shrinks to 15.25 inches with the pistol brace folded to the right of the receiver. Weight is 5.9 pounds. A total of two 25-round UMP magazines arrive with the LWRC SMG 45.


LWRC decided to utilize HK’s UMP 45 ACP magazines to feed the SMG 45. This stemmed from the original foreign solicitation that spawned the SMG 45 in 2015. LWRC needed a reliable high-capacity feeding means in a timely manner. This allowed the manufacturer to focus on other components during the design stage instead of having to invest the time and energy into creating one themselves. The UMP magazine was an easy decision based on this.

LWRC equipped its SMG 45 with a SB Tactical Folding Brace. The subject of braced pistols has been covered in depth over the last several years. The fact that the SMG 45 is legally classified as a handgun offers users who have a concealed carry license a certain amount of flexibility compared to a true rifle or NFA SBR classified weapon if desiring to pursue off-body carry.


I mounted a Vortex Razor AMG UH-1 holographic on my SMG 45 during testing. The AMG UH-1 is Vortex’s entry into the holographic red dot sight genre. The Vortex UH-1 holographic reticle has a (1) MOA center dot, surrounded by a larger circle. There are hash marks at the 9:00, 12:00, and 3:00 positions for additional sighting reference. Lastly, a small triangle in the 6:00 opening is specifically designed to be a CQB sighting reference to account for bore-to-sight off-set at ranges 7 yards and in. Vortex designed the Razor AMG UH-1 to have a lower 1/3 co-witness with standard iron sights.

LWRC SMG 45 Testing

I used an assortment of both premium self defense JHP and FMJ ammunition during my evaluation. Included was Hornady 230 grain, Winchester PDX1 230 grain, Federal Premium 230 grain Hydra Shok, Black Hills Ammunition 230 grain JHP, Winchester 230 grain FMJ and SIG SAUER 230 grain FMJ & V-Crown JHP.

Firing was at a relatively steady pace with different shooters running the SMG 45 through its paces on plate racks, dueling trees, and other drills. The SMG 45 had no issue digesting JHP profile bullets. This is an important issue as LE agencies and civilians use expanding ammunition to limit over penetration in CQB situations, not to mention increased terminal effectiveness. The recoil impulse was smooth with accurate strings of fire possible.

Drills around barricades and moving through doorways had the LWRC SMG 45 showing its merit. After all, the SMG 45 is a 6-pound AR-pattern weapon known for excellent ergonomics and handling. The range evaluators on hand were struck by how easy it was to shoot while moving. This is surely a result of LWCR’s inertia-driven, delayed blow-back operating system, which manages recoil as designed. The Vortex Razor UH-1 optic gets some credit in this as well.

Final Thoughts

The LWRCI SMG 45 places real power in a compact, accurate, and reliable package. Is it a pack gun? Absolutely. Home-defense gun? You bet. Military and law enforcement? Obviously. It will be interesting to observe if the LWRCI SMG 45 is widely accepted and adopted by LE and military units in the coming years as they phase out their older model SMG weapons. This will no doubt also influence private citizens to consider it a viable option. For more information, please visit

LWRC SMG 45 Specs

  • Caliber: .45 ACP
  • Barrel: 8.5-inch Cold Hammer Forged Chromoly Steel Barrel
  • Weight: 5.9 pounds
  • Length: 15.25-26 inches
  • Muzzle Threads: .578-28 RH
  • Rifling: 1:16 RH | 6 Grooves
  • MSRP: $2,995

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