The Glock 20 is a brute. It can stand up to a severe amount of pounding from 10mm pressure. When the Colt Delta Elite came out (1986), the Norma ammo at the time was brutal. Many Delta Elites suffered cracked slides and frames.I consider the Glock 20 the best platform for a full sized 10mm pistol shooting full house 10mm loads. The other firearm that really performs well with the 10mm is the S&W 610 revolver.
I've heard the brens are expensive, finicky and hard to find any parts for. Where is the glock 29? Subcompact and 10 monster rounds. I rented one at the range. It was a beast, but would make a vicious carry gun.
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A kb can be a problem with a Glock barrel if you are going to shoot lead or reloads. If I owned a Glock 20, I would get a replacement match barrel from Bar-sto or EFK. The full-cap mags for the Glock 20 are a problem too. They are the rarest and most expensive Glock pre-ban mag. I still believe that the Glock 20 is the most durable platform for a 10mm outside of the S&W 610 revolver.
BG3, the Bren was a huge pistol, about the size of a CZ97. It was a 2 tone all steel pistol. Usually the ones you see with one finish were hard chromed, a-la Miami Vice. The Bren suffered from feeding problems and parts breakage. Dornaus and Dixon also had a rough time getting mags produced for the Bren. Toward the end, many Brens were shipped with no mag. One interesting feature the Bren had that I haven't seen since was a push button slide firing pin safety in addition to a standard frame mounted CZ style safety. Richard Voit tried to revive the Bren in the early '90's under the name Peregrine Falcon, but to no success. Triton Ammo supposedly was seeking to build and release a new version of the Bren. They too have since dropped the project. In retrospect, the Bren was a really cool pistol and brings major $ on the collector's market, but I hardly believe it was or is a better pistol than anything currently on hand today for the 10mm. It was just the first.
I'm voting Glock 20. I really like the Colt Delta but in my opion it doesn't hold up with the heavy loads like the Glock. I have no experience with the Bren or S&W. I do like the looks of the new EAA with the extended slide.
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I have to admit though I didn't cast a vote. One of the great things about the 10mm is its versatility and so I guess it kind of depends on the job you're asking it to do when asking which 10mm is the best.
While there's quite a few other 10mms available, one of the best that wasn't listed is the S&W 10xx series. The S&W 1006/1066/1026/1076/1046/1086 are all strong, well built pistols. Granted they are no longer in production, but they aren't too tough to find on the used gun market for reasonable prices. Currently I use a 1086 for CCW purposes and it's an excellent gun. The Glock 20 is also a great gun, but for me it's just a bit too big for most purposes with the possible exception of open carry when camping/hiking. Here in Oregon we don't need any special license or permit to hunt with a handgun so while I always use my Ruger .30-06 I also pack my 6.5" 610 in case I get a close up shot. The 1911s are sweet shooting guns, but for most purposes I'd prefer a shorter barrel length. Now if someone would make a Commander sized 10mm I'd buy one in a heartbeat!
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