KelTec Announces the ST50… Err, I mean KP50

I got a kind of exciting email earlier today from Keltec announcing the new KP50 and MP50 5.7x28mm pistol and subgun. I immediately recognized it because I had a chance to shoot the Stuff & Things ST50 at GunCon last year.

The ST50 was pretty awesome. It was a new chassis for the KelTec P50 with much better ergonomics. I know KelTec has shown the ST50 on their social media before, and I thought it was awesome that they were working with the S&T guys. Until I found out that they weren’t.

Keltec KP50 Defender

What is the KP50?

Well, if you’ve seen the ST50 floating around since early last year on social media, then you pretty much know what the KP50 is. It essentially takes the barreled action of the P50 and flips it upside down so that the mag is much more accessible and lows from below. No more opening up a clam shell to do mag changes. It also uses an AR pattern grip and can accept a brace or a stock. It feels like an entirely different, and better gun. Mag changes are dramatically easier and faster.

It’s a great design. Much better than the original P50 in fact. It’s just a shame that Stuff & Things came up with it early last year and KelTec doesn’t seem to be giving them any credit for it.

Stuff and Things Mag Coupler from Summer 2025

S&T even designed a mag coupler last summer. I know they aren’t the first to make a mag coupler, but they did make one for use with their ST50 chassis, much like KelTec now has one for its KP50.

Differences?

So, is the KP50 a direct copy of the ST50? I don’t think so from looking at the pics. It does look like the grip frame differs. They use different safeties, and apparently, fire control parts, and it looks like a different style mag release. Arguably, the ST50 is a better design as it will take any AR fire control unit, and it works with a Hoffman Super Safety.

Still, I don’t think anyone can question where the “inspiration” for this came from. Especially when I talked to the folks at S&T, and they’d actually sent KelTec a couple of ST50s to work with, and thought they had a good working relationship with them. I’m guessing Keltec will say it’s different enough that it’s their own thing, but you’d have thought maybe they could at least credit S&T for the concept at the minimum. Or just worked with those guys and licensed their design or something.

KelTec certainly has had folks in the industry rip off their designs enough that I’d have thought they’d be a little more sensitive to this kind of thing. Especially with a company like Stuff and Things that was promoting their products, not copying them.

Stuff and Things ST50 from GunCon 2025

Options

Well, the KP50 has an MSRP of $1,399.00. Or you could buy a P50 on the used market and get an S&T kit for it for $239.99. Honestly, the KP50 is a nice design. But the way they dropped it without even mentioning Stuff and Things just leaves a bad taste in my mouth. I hate when stuff like this happens in the industry. I like KelTec and have a number of their guns, and have had others over the years.

I had a nice chat with some of the folks at SHOT and was hoping to get one of the P3AT’s to try out. I was interested in the KP50, too, until I saw how this played out. At this point, I guess I’ll wait and see how things play out, but I’m hoping KelTec at least acknowledges where the idea for the KP50 came from.