Smith & Wesson Pistol Generations Guide
Understanding Smith & Wesson Semi-Automatic Pistol Generations
Navigate the complete history of Smith & Wesson pistols with this comprehensive guide to identifying and understanding each generation. Whether you're looking for parts or trying to identify your pistol, this guide will help you understand the differences between 1st, 2nd, 3rd generation, and modern M&P series pistols.
1st Generation (1950s-1970s)
Identification: Simple two-digit model numbers
Key Models:
- Model 39 - 9mm, single-stack, alloy frame (first DA/SA auto)
- Model 52 - .38 Special wadcutter, target pistol
- Model 61 - .22 LR Escort pocket pistol
Characteristics: Basic model numbers, pioneering designs that established S&W's entry into semi-automatic pistols.
2nd Generation (1970s-1980s)
Identification: Three-digit model numbers (improvement on 1st Gen)
Key Models:
- Model 39 Series: 439 (alloy), 539 (steel), 639 (stainless) - single-stack 9mm
- Model 59 Series: 459 (alloy), 559 (steel), 659 (stainless) - double-stack 9mm
- Model 745: .45 ACP target pistol
Characteristics: Three-digit numbers, improved sights and features over 1st generation.
3rd Generation (1980s-2000s)
Identification: Four-digit model numbers with specific meaning
Model Number Breakdown:
- First digit = Caliber/Frame Size: 3=9mm compact, 4=.40 S&W or .45 ACP, 5=9mm full, 6=9mm/.45 ACP, 10=10mm
- Second digit = Frame Material: 0=alloy, 9=stainless
- Third digit = Features: 0=DA/SA, 1-4=various trigger/safety configs, 5-6=compact variants
- Fourth digit = Generation/Variant
Popular Models:
- 9mm Compact: 3904, 3906, 3913, 3914, 3944, 3953, 3954
- 9mm Full-Size: 5903, 5904, 5906, 5943, 5944, 5946
- .40 S&W: 4003, 4006, 4013, 4043
- .45 ACP: 4505, 4506, 4513, 4516, 4526, 4536, 4546, 4553, 4563, 4566, 4576, 4583, 4586
- 10mm: 1006, 1026, 1066, 1076, 1086
Characteristics: Four-digit codes, most diverse generation, many variants with different trigger systems and safety configurations.
Modern M&P Series (2005-Present)
Identification: Named "M&P" (Military & Police) instead of numbers
Key Difference: Striker-fired polymer frame (not DA/SA hammer-fired like earlier generations)
Model Lineup:
- Full-Size: M&P 9, M&P 40, M&P 45
- Compact: M&P 9 Compact, M&P 40 Compact, M&P 45 Compact
- Shield Series: M&P Shield (single-stack slim), M&P Shield Plus, M&P Shield EZ
- M2.0 Series: Updated M&P with improved trigger and grip texture
- Specialty: M&P Bodyguard 380, M&P 22 Compact, SW22 Victory
Characteristics: Striker-fired, polymer frame, modular backstraps, modern design competing with Glock and other polymer pistols.
Parts Compatibility Quick Reference
Between Generations: Parts are generally NOT interchangeable between different generations (1st, 2nd, 3rd, M&P).
Within 3rd Generation:
- Caliber-Specific Parts: Barrels, slides, magazines, extractors, ejectors, firing pins
- Interchangeable Parts (same frame size): Triggers, hammers, sears, disconnectors, springs (in most cases), grips, sights
Magazine Compatibility:
- Magazines are caliber-specific and NOT interchangeable between calibers
- 9mm magazines only fit 9mm pistols
- .40 S&W and .357 SIG magazines may interchange (same case diameter)
- .45 ACP magazines only fit .45 ACP pistols
Need Help Identifying Your Pistol?
Look for the model number stamped on the frame, typically on the left side near the trigger guard or on the slide. Use the guide above to determine which generation your pistol belongs to, then browse our model-specific collections for the exact parts you need.