It’s rather uncomplicated (though not necessarily easy!) to make something like a H&K VP9 concealed carry holster because the VP9 is the VP9 and that’s it. Only H&K makes them!
With the 1911 pistol…it’s a little different. Because the blueprints are public domain, anyone can make one. Dozens of companies make nothing other than 1911 pistols and their variants. A number of them change things here and there so their 1911 pistol is different from someone else’s.
Speaking of which, that’s why we don’t offer a ShapeShift for Sig Sauer 1911 pistols…yet, anyway. (It’s in the works!) The Sig Sauer 1911 pistols have a differently-shaped slide. The slide is slightly squared, compared to the filet of the typical 1911 slide. There is also the horizontal rib machined into the slide, giving them a similar appearance to Sig Sauer’s P220 and P226 family of pistols. Therefore, a standard 1911 holster isn’t going to fit a Sig Sauer 1911 pistol.
We also can’t necessarily get an example of every 1911 pistol from every single producer, nor be expected to. So, we have to come up with a holster that fits the greatest number of pistols based on a sample of guns that we can reasonably obtain.
Granted, if everyone just made GI guns then this would be no big deal, talking about it wouldn’t be necessary and so on. Then again, if that’s all anyone made, that would be boring! The fact that 1911 pistols vary so much does have some implications for fitment.
First, we can’t necessarily guarantee that YOUR 1911 pistol will fit the ShapeShift. If we couldn’t confirm that make and model in our fitment process because we didn’t have one on hand or didn’t have one, we can’t say to a certainty that it will fit. However, we can make an educated guess as to whether your 1911 pistol will fit the ShapeShift 1911 holster.
Second, unfortunately there will be some people whose 1911 pistol does not fit the ShapeShift 1911 holster shell. The further a design strays from the typical 1911 pistol, the greater the chance that it won’t.
Source: Alien Gear Holsters