Talk about Sig discontinuing the current X5, its being false, then being sold at discount to allow for new model with updated optic mounting plate, is interesting A different viewpoint.
Bought a new, upgraded P320 X5 recently. With mixed factory rounds (9mm), it severely bulged 13 rounds straight (seen later), and blew out a 14th, ejecting the extractor to obscurity.
Called Sig and was told by customer service:"We have never heard of this before". Examination of the pistol revealed, and using precision metrology equipment, that chamber depth was indeed too short, leaving the case rears unsupported the full circumference of the chamber. In fact the blown case was almost severed into two pieces, not just at the feed ramp. Additionally, there is a very heavy and deep radius around the chamber mouth. The use of mixed factory rules out the "bad case" excuse, often cited. Comparison of many different 9mm handguns in collection (Beretta, Sig P226 X5, 226, 229, Browning, 1911, Smith and Wesson 5906 PPC, 469, Astra 600, Kahr, Luger, Colt 2000, even a Hi point, showed much more chamber/case support. Search revealed at least three federal lawsuits over blowouts, on in Western District of Missouri, a class action, and repeated blow ups. There are suits over safety as well, with several injured law enforcement officers. Noting the date of the suits, and my recent "Never heard of this" comment from Sig, it is truly almost impossible that Sig did not know of this. The local gun shop (Duncan's Gun Shop, Wilkesboro, N.C.) was of absolutely no help. I obtained a return authorization and returned the pistol to Sig. 12 days later, it returned, citing only a extractor replacement, examination and test firing, all reported as normal. However, back to the metrology equipment, the chamber depth was most definitely not the same, with deeper seat. Headspace was in normal limits. As a mere chamber ream would open headspace, it must be a new barrel. Radius appeared same. Combination of the many suits far predating my contact with Sig, and the discrepancy shown by metrology, there is cause to suspect Sig is not being totally honest here. I have personally met with others who were not as lucky as me, sustaining injury. "We never heard of this" was cited as well. IT is interesting that the customer service rep is fast to ask about injuries or emergency room visitation.
Out of lock firings were cited in one suit; technically this is right and wrong. Mr. Gray with GrayGuns, was quite argumentative over this out of lock issue, citing "It is impossible for the X5 to fire out of battery". He is half right. When the pistol if out of lock and fires, there is catastrophic case failure. The disconnector is set to prevent this. However, a situation of gross headspace can also mimick the same, or in the case of failed case support, say due to tolerance stacking. Generous radius, shallow chamber reaming, but with headspace appearing normal, leaves unsupported case web area. This can happen because the barrel remains in lock, disconnector not engaged. Thus the result is a blowout with the action indeed locked. So, technically, Gray is correct. But, as Paul Harvey once said: "Here is the rest of the story". Then the issue of reload use was suggested. In my case, no. However, in over 40 years of reloading, including many .38 Super and 9mm loadings (Not major 9), I have never experienced a blow out of any nature. The only problem encountered, ever, was a case partial separation loading for the 5.7x28, years ago, when I first started loading that caliber for the FiveSeven pistol. That was near the shoulder and was a repeated sizing/shoulder setback issue native to that cartridge.
But I digress, my point here is, in my opinion, Sig knew it had a problem with the X5 barrel. It chose not to do a recall and rebarrel. Much like they did a voluntary send back for upgrading secondary to drop fires, but no recall. Rebarreling would be too expensive. The approach is to replace those sent in, but initially blame on "bad brass", reloads, or some other "operator" error. I did contact several nationally known gunwriters, who expressed interest, but were "unaware" of the problem. But then, when was the last time a gunwriter wrote of such issues? I can't remember. They wish to remain cozy with the manufacturers. I am concerned with shooter safety. I did recommend, based on this, that Duncan's withdraw this pistol from stock for sale, but seemingly they have refused. They are now very well informed as to the safety problem, as should all gunshops. Some have had glowing positive experiences with the X5, some clearly have had near catastrophic experiences. So, any new model change, say to incorporate a new optic base, does raise my antennae. It avoids facing the problem. FYI.