The Smith & Wesson M&P45 with Thumb Safety is a striker-fired .45 ACP pistol with a 4.6-inch barrel, 10+1 capacity, and a stainless steel slide over a polymer frame. It weighs 27 oz and measures 7.9 inches overall. The thumb safety is an optional feature on the M&P45 line -- this variant includes it, which matters to buyers who carry with one in the chamber. 
 

Key Specifications 

• Brand: Smith & Wesson 
• Model Name: M&P45 (Thumb Safety) 
• Caliber: .45 ACP 
• Action: Striker Fire 
• Capacity: 10+1 rounds 
• Barrel Length: 4.6 inches 
• Overall Length: 7.9 inches 
• Weight: 27 oz (1.7 lbs) 
• Finish: Matte Black/Stainless Steel Slide 
   

Detailed Features 

The low bore axis reduces felt muzzle rise during rapid firing. The 18-degree grip angle is designed for a natural point of aim. Four interchangeable palmswell grip inserts are included to fit different hand sizes. The grip texture is aggressive enough to hold under wet conditions. The M&P trigger has been reworked from earlier generations for a lighter pull weight with tactile reset. The manual thumb safety engages and disengages with a consistent click. 
 

Target Audience 

Shooting the .45 ACP in a full-size platform. The 10+1 capacity is standard for this caliber and frame size. The thumb safety version is specifically sought by shooters who were trained on 1911-style manual safety operation, or by those who carry in environments where an external safety is preferred or required. 
 

Usage Scenarios 

• Home defense where .45 ACP terminal performance is prioritized and the thumb safety adds a layer of confidence 
• Duty or service use where a thumb safety is mandated or preferred 
• Competitive shooting where the .45 ACP caliber and grip ergonomics suit the shooter's technique

Owner feedback on the S&W M&P45 with Thumb Safety reflects the broader M&P45 reception, with the thumb safety adding a specific debate point.

Ergonomics and comfort are the top positives. The interchangeable grip inserts let most hand sizes find a workable fit, and the 18-degree grip angle comes up often as a natural shooting position. Owners who shoot for extended sessions mention reduced fatigue compared to more upright-gripped .45 platforms.

The .45 ACP caliber choice is intentional for this buyer -- most owners specifically selected it for terminal performance in defensive use, and the stopping power argument is the starting point for the purchase decision.

Range performance is generally well-rated. Owners report tight groups at typical defensive distances, and the low bore axis is credited for manageable muzzle rise given the caliber.

The thumb safety generates the most discussion. Owners who wanted a safety are satisfied with its positive engagement and consistent feel. Owners who tried the no-safety version and prefer it note that the safety adds a small step to the draw stroke that takes training to make automatic. This isn't unique to this pistol -- it applies to any manual safety on a carry gun.

Weight at 27 oz for a .45 ACP polymer pistol is on the moderate side. Full-size carry users sometimes note it's heavier than their 9mm alternative, which is true.

Trigger pull gets split feedback. Many owners find the factory trigger acceptable for a defensive gun; competitive or precision-focused shooters sometimes replace it.