The pistol's use in the military, or most anyplace else, is typically as a defensive weapon, or a secondary weapon that is faster to transition to during an emergency reload/stoppage with your rifle during CQB. Reliability and longevity are the two most important factors IMO and pretty much anyone who ever taught me who was somebody of note said the same- the calibers most common to combat pistols are all within pretty close parameters in terms of stopping power, although the 357 Sig does have pretty good results with the Air Marshalls (pretty much a 100% kill ratio), shot placement and training is a major factor in that statistic IMO, as their training and continuous skill maintenance (at least used to) ensure pretty high hit ratios.
Danny, the trigger possibly in the Glock you were using was either a factory 8 lb or worse, even 12lb or New York triggers are known to get into the military pistols. If you tried one with a 3.5lb discon/trigger that was tuned up, it would have shot a lot better for you I would wager. I shot a BHP for years as well, and worked for Sig Saeur Academy for many years, shooting many different types of pistols. For me the Sig 226, our flagship, shoots and points badly for me due to the high sightline and general shape - it just points very uninstinctively for me, and I have to hunt for the sights constantly. Sig 220 or 1911s, no problem with that at all. Everybody has different body mechanics, so the best bet for the military is go with something that is as common as possible, and reliable as possible.
The 92F/M9 always has had reliability issues, and rarely get to that 20k service life count without some sort of failure. Locking lugs shearing off being a big one, among many others. Talk to any Beretta armorer and you'll get the same story almost verbatim. Other pistols have issues as well, polymer framed pistols tend to be outlasted by steel frame, but there is cost and weight penalties with that as well. IMO the US military would be best served by a pistol with ammo already in common usage (9mm or .45) and made with a steel frame. After that, just pick the ones that get through the tests with the highest round count, and best/simplest controls and manufacture combined.
When I did PSD work our company bought G19s, and they worked well enough, and we also had the option to carry what we wanted, so I sometimes used a 1911 as I've shot them for years and just prefer them, plus working for a company that was run by mainly x US Army guys who had shot nothing BUT 1911 for years, it was very common.
The talk about a "harder hitting" pistol though, I just don't see it. Not unless you want to get into specialized ammunition. It's out there. 10 years ago I had 75gr +++p frangible stuff doing warp speed out of a G19 barrel, we're talking going through both panels of older 2a vests we hung on the range. Also very very hard on plastic framed guns, 2000 round service life expectancy with a Glock pistol, however it WAS very lethal compared to most pistol ammo. You just can't have it both ways IMO, you either have a lot of noise, recoil, flash, and wear to go with that lethality, or you don't, and have common ammo. Common ammo is probably the only way the regular units can go in the military. Large frame revolvers are built strong to take those 357 and 44 mag and even higher loads. Put those into an auto though - well, I've seen Desert Eagles, AMT and Automags discombubulate with great frequency on the range, with not a lot of rounds put through them. The nature of the semi auto pistol with that huge load tends to break things, ask any range that rents out such pistols how long they last, and the answer is not long.
The new VP9 HK pistol was mentioned, however in my experience few if any polymer framed guns last much longer than that 20k service life expectancy from the factory. Glocks, Sigs, HKs, you name it, if it has a plastic frame, typically some sort of malfunction, often catastrophic or at least very expensive and time consuming to repair is in the near future around 20k. This is unacceptable IMO for a military general service pistol. There is no reason that number can't be doubled or even tripled, and a steel frame pistol built to be reliable and long lasting is a capability many manufacturers do posses. It's time the US military chose one, or put out a competition for builders to make one.
edit - Smoe, the 45 GAP and other various calibers already exist, but IMO to go to a non standard round would be too expensive for such a large batch of pistols. 9mm or 45 will likely end up being the caliber of choice in this spending environment with defense.
