Copy and pasted from my reply re same question for U.S. Marines...
Is this thread regarding the new U.S. Military directive for the "Modular Handgun System" or just a general question on people's favorite choices?
If it's the MHS program then forget the 1911, because the military wants something more modern.
As much as emotion and sentimentality may want some people see the return of the 1911 in active service, I don't think the classic 1911 as we know it (all steel, single stack, .45 ACP) will ever be adopted by the U.S. Military as a standard, general issue sidearm. Maybe for some special units but doubtful for a standard issue.
Love or hate the modern polymer handgun designs, they offer much more flexibility in terms of light weight, capacity, modular design (one size fits all/interchangeable grips/ambidextrous) for today's soldier who already has to carry 50 lbs worth of gear. Why add to it a 2.5 pound, 5" long 1911, when there are 25 oz, 4 to 4.5 inch polymer sidearms available?
Also, these are soldiers under stressful conditions, not IPSC shooters under controlled conditions, so safety will probably be a huge requirement meaning they will probably look for a DA/SA with an external hammer and decocker. I could be wrong but this has been the general path since the Beretta M9.
Add to this that there are prevailing attitudes that the classic 1911 has inherent disadvantages. I'm not trolling here because I love the 1911, but those are some people's feelings: pistol-training.com » Blog Archive » 1911 Cult: Cracks in the Armor
So putting aside what I would like to see as the next MHS sidearm, if I were a betting man I would think the next general issue sidearm will be...
Top pick: Beretta PX4 Storm SD in .45 ACP. According to the biased source, Beretta USA, this one finished at the top of the scrapped Joint Combat Pistol competition. Also, it can be tooled in the USA by Beretta USA, and there will be a lesser learning curve as they switch from the M9 since the controls are the same due to the similar platform.
- Beretta 96A1. Similar to above in that it will be less of a learning curve for current military to adapt since many of them would be familar with the standard Beretta controls.
- Sig Sauer P226 in .40 S&W. Again...because many current military personnel are familiar with the platform and Sig Sauer USA can crank them out in Exeter.
- HK45. It is highly modular, meets safety criterias, chambered in .45 ACP, mimics 1911 controls and grip angle...
- Glock, or maybe even the FN Five Seven? I'm not sure what the U.S. Military's stance on striker fire pistols would be. I have read conflicting things regarding whether they would want an external hammer for the perceived reasons that the external hammer would be a visual and tactile safety feature (i.e. easier to tell if it's cocked or not), and also "second strike capability".
NOW, I know a lot of you will chime in and say "second strike capability" means nothing because you should tap-rack-bang... but, I have heard conflicting things regarding the military's stance on second strike capability. I reiterate, this is not my stance on second strike capability but just thinking what the bureaucrat at the Pentagon would be thinking.
Perhaps someone in these forums can find the requirements of the new MHS trials?