Not all slides are created equal. Fortunately, we can help you look for important features when shopping for an aftermarket slide.
The material used when manufacturing a slide is of utmost importance and plays a significant role in slide longevity.
You will see two common materials, 17-4 stainless steel and 416 stainless steel. Which one is better suited for a pistol slide?
The answer is 17-4.
When hardened, 17-4 has better mechanical properties than 416 across the board, including its overall strength, but one crucial property stands out, its resilience. The measurement of resilience in a material is its ability to absorb energy.
Fun fact: 17-4 has more than 4 times the resilience of 416.
This means that 17-4 is 4 times more resistant to cracking than 416. Are these numbers meaningful for a slide? Absolutely. A slide is subjected to impact forces especially from the firing pin on the breech face and the barrel hood lock up.
There exist a significant number of cases showing cracks on the breech face and barrel hood lock up of slides made with 416 stainless. Such occurrences have not been reported with 17-4 stainless.
We personally experienced a total failure after shooting as little as 500 rounds through a 416 stainless slide, when the barrel hood lockup cracked and took the barrel with it.
This was an eye opener and confirmed the superiority of 17-4, with which we have as many as 30,000 rounds through one slide with no reported failures and signs of cracking.
Perhaps a less crucial but significant metric is the cost of 416 vs 17-4, which is 15-20% cheaper on average. This might be of consideration when making your final decision.