ilisdad: After thirty years, I'm retired le, but while "on the job" I had the good fortune to work with many law enforcement agencies and my observations don't jive with yours at all. Which is why I asked if you were privy to independent evidence (i.e., documented departmental tests where the results are quantified and verifiable). If you were to rely soley on my "experience" you would believe that Ithaca 37s are known to drop loaded rounds from the gate when the slide is activated; that Remington 870s can (through operator error) be induced to jam where the "fix" is almost impossible to do while under fire and that the long discontinued S&W Model 3000 may have been the best police pump shotgun ever made. But past my opinions based on my experience and your opinions based on your experience, I'm looking for evidence as opposed to hyperbole.
To be honest, all I have to go on is personal experience, and the fact that the 870 has outlasted all other platforms, and it obviously is not due to cost. This being said, I do agree that hard numbers would be fantastic, but you know as well as I do that they are hard to come by.
The closest I can come to an official study is the fact that the Oklahoma Council on Law Enforcement Education and Training will not allow any Winchester 1200/1300 in the basic or instructor firearms training. From what I can gather, the reasoning for this is twofold. 1) Due to the Winchester's design, it is impossible to place the shotgun on "cruiser safe", as the hammer must be cocked to place it on safe, 2) The folks who oversee the training have seen far more failures with this platform than the Mossberg or Remington, and a failure in training can set an entire academy back.
Again, this is basically heresay, but its all I have. I have seen, with my own eyes, more failures with the Winchester than the Mossberg and Remington. This is not to say the other platforms are flawless. The Remington is prone to operator failure, as you described, due to its shell lifter design. The Flex-tab was an improvement, but it does not aolve the issue, only training can do that. The Mossberg has a better lifter design, but the internals arent as sturdy as the Remington, and the plastic pieces found on the 500 and 590 are a liability IMO, having broken both safeties and triggerguards myself. The 590A1 cured a lot of these ailments, but at a heavier weight penalty. The Mossberg still suffers from a less smooth action, and the aluminum receiver, less of a liability that often mentioned due to its method of bolt lockup.
I do tend to agree with you on the S&W, as I have played with several of these. These guns took the benefits of the 870, and improved upon them, and when paired with Howa's fine manufacturing skills, made an incredible fighting shotgun.
I suppose when it comes down to it, all we have are personal experiences to rely on, as it is often hard to trust even structured studies because they are often skewed by tester and agency bias. Based on my experiences, only the Mossberg and Remington are viable fighting guns for me, and I own both. I feel the 870 is a functionally better weapon, but the Mossberg is no slouch.
It is my understanding that the military ran some extensive objective tests and eventually adopted an alloy-receivered Mossberg for service duty (I confess that I don't know just how factual my "understanding" is).
The Mossberg 590 was the only shotgun offered for testing. Remington chose not to submit an 870 for the trials, as they had nothing to gain. While it is true that the 590 passed the trials, and spawned the -A1 version based upon military suggestions for improvement, it did not "beat" any other shotgun, as it was a one-gun race.
