Pistols can be finnicky creatures. There are dozens of moving parts and springs – many of them born from different manufacturers all over the globe – required to work in concert with one another to contain a miniature explosion, accurately launch a round at a target, and then perform a complicated dance to load a new round and start the process all over.

Unfortunately, manufacturing all of these parts and getting them to play nice together can present unique challenges, some of which don’t make themselves known even during extensive pre-production testing. The smallest little machining flaw during production can lie dormant, not becoming apparent until that part meets the rest of the firearm it was intended for.


We discovered shortly after the launch of the April 2021 batch of Vapor uppers, that a few of our customers were running into an issue that was causing the slide to bind and get stuck to the rear when racked, even when the slide lock is not engaged.

After calling the team in on the weekend and performing an all-hands-on-deck investigation, we discovered that a small percentage of this particular production run was affected by one of our tools wearing faster than we had anticipated and causing a tolerance stacking issue between the barrel and the slide.

It’s worth noting that we do intentionally engineer and manufacture our products to hold very tight tolerances. This level of precision allows for a tighter lock-up between the barrel and the slide, and provides more consistent cycling and improved accuracy. Many of our slides require a few magazines worth of live-fire to break in the friction surfaces and ensure 100% reliable cycling. In this case, however, a small number of these recent Vapors were machined a bit too tight, and once coated and installed, began to exhibit this “slide-stick” issue.


Customer satisfaction is and will always be our primary motivator, and as a result, we have already taken steps to rectify the problem for any of our Vapor customers who are experiencing this issue. By our calculations, less than 10% of the overall production run was affected by this tolerance issue, but we absolutely intend to make it right for 100% of those affected.

If you purchased a complete Vapor upper from the affected production run (launched 4/20/21) – either directly from or through an authorized NineX19 dealer – and are experiencing temperamental slide lock-back, please fill out the form below.

We will email you a pre-paid return shipping label to get your Vapor upper sent back to us at no charge to you. We will then fix the issue, personally function test it on a variety of demo frames, and send it back to you. We do our best to maintain a sub-2-week turnaround on these service requests and we always keep an open line of communication with you during the entire process.

Your complete satisfaction is our number one priority, so rest assured that we will not leave you hanging or keep you in the dark on anything along the way.

Vapor Service Request
Please enter your original order number from If you ordered from a dealer, please enter the name of the dealer here. (If you are unable to locate your order number, please enter "N/A".)
Please enter that address that you'd like your Vapor returned to once servicing is complete.