KT Chaser and Eraser Conversion

[Ratzkie]

New update:
After getting some VERY precise measurements, I realized orings are overkill. I have ordered .5 OD, .035 wall brass tubing. That makes my ID about .430, and the original bolt measures in at about .428... So it should be a press fit onto the bolt, and I will polish the OD of the brass and the ID of the bore to match. I have ordered a 400 grit Flex-hone for the bore.

Next time, will our hero get everything to work???

[Ratzkie]

It's been a hot minute. I got everything working, short of actually putting a 12 gram in it and airing it up. I'm sort of stalled right now on getting a working mag set up. Yeah, I said I have all the files done, and I do- they work, but the little fiddly bits are troublesome. I'm working on sourcing some parts so that we don't have to tear apart stock mags to make 50 cal mags. I'll be approaching my friends over at the new ImpossibleCreations.ca to get the mag parts SLS printed in nylon, since they are thin and fragile. Then I have to find some pins and small springs to finish the job. Getting close to having the first 50 cal KT pistol, and FSR ready at that!

[ChoSanJuan]

Just made a deal for a NoS Chaser. Hoping to see this come alive!

[Scougar]

Still have mine sitting, and want to convert. I almost think making a new body would be easier though due to limitations in the material and choices Kingman made in the breach area

[Ratzkie]

It's been a rough couple months, tbh. I dropped all of my projects including this one.

This project is on the list to finish up now that I'm interested in being creative again- I'm back on the hunt for getting the mag parts made. IC wants around $50 or $60 per mag (plus cross border shipping), and I'm probably going to need two or three made before I even dial in the printing tolerances for their machine. I may have to post the files to Shapeways so everyone can order them and assemble themselves. I would make them myself but increasing the size of the round makes for thin walls that FDM printing doesn't make well or strong. I am looking into resin printing them as well, but that will potentially make them more brittle.

Re: Scougar- we should talk about this. We could print new uppers and sleeve them in brass. But at that point, we might as well make a new lower to handle a slightly larger mag. Full internals parts kits are certainly easier to find than mags though.

[Ratzkie]

Alright, so 2020 and 2021 was certainly a time to be alive. And of course I got laid off last week.

New hot scoop:
I'm making 3d printed lowers. The reason behind the new lower is to make larger 50 cal mags, as the walls are just too thin to stand up to regular usage in the field. The other reason is to make custom lowers to match the custom upper body kits, like the M6G. The grip itself will not get any larger (thankfully), I am just removing material from the inside.
You can catch my work on this over at twitch.tv/ratzkie, the last episode was creating the lower. I am currently tweaking the design, but test prints just for bolt holes are two hours long so there is a lot of waiting. I have removed the rubber side panels and added some grippy grooves. While the idea is for 50 cal conversion, I could be tempted into making custom bodies for 43 cal setups as well, just to please everyone.

The pistol itself is still waiting on fps testing until i can get a mag loaded in it- either i tear apart my only 43 cal mag or i buy a rebuild kit that has mysteriously become available on ebay? Parts for this pistol and for mags have become available again, and my only guess is that someone found a box in the back room that hasn't been looked in for about 10 years. This is probably a sign that I should stock up on rebuild kits to build mags, but I can't justify the cost right now of a full stock up.
I also just bought another pistol from another member here, excited for that to come in- it's going to become the base for a Deagle body for a friend, but it will stay 43 cal for now.

[Ratzkie]

Quick update. I'm not dead from the 'rona yet. Thanks for that, world.
I have created full lowers for 43 and 50 cal mags. I just made a full blown Desert Eagle upper body, Halo lower to go with the Halo upper kit, and I have orders for body kits that aren't even done yet lol. The lower I have sitting her has all of the internals from the stock lower moved over to it and it appears to be working properly.

On the 50 cal front, I just need to get the tolerances worked out on the magwell and assemble it. Someone found a box of KT parts in the back room and if you are planning on getting more mags (either 43 or 50 cal) you should hit up ebay and grab a couple mag rebuild kits. They are $14 each or so. As soon as I get the mag tolerances working I will print a new set of everything and put it together.
At this time I don't really know if I'm going to offer 50 cal boring as a service to go with my mags and lowers. If enough people commit, and send them to me, I could go back to the machine shops in the area and start getting quotes. But for one here and one there, its going to be on you to find your own local shop.

[Ratzkie]

In the home stretch guys. I finally got the full lower printed, and it turns out I needed to tweak the trigger group pins slightly. Test print completed, the marker now fires, and we are currently printing the full lower (for the... idk like 6th time). It will be done around 9pm tonight. The only feature it doesnt have is a mag lock/release. The only feature it may need to have tweaked is the location of the magazine activation pin, right behind the trigger. I haven't worked on that one because I haven't had mags.
Speaking of mags, I have a new model for the 50 cal fsr, I bought two mag parts kits, and the what I have so far assembles and works. Just need to get the lower printed so I can test the entire system.

Happy 2022, the Year of the 50 Cal Chaser!

[un2xs]

So... Basically what you are saying is that you gave up on modding the existing gun and are making a completely new one, complete with new mags?

[Ratzkie]

no, i ended up making the lower because it was a commission. Client wanted a Halo lower to go with the Halo upper and was willing to pay for it. So I made it. But first I needed a working lower so that I could mod it into what he wanted. From there I took the base file and modified it slightly for a larger magwell and added a front rail, that's all. The 50 cal mags for 43 cal stock lowers are still a thing, they are just very flimsy and I don't know how many of those I'm going to offer because of it.
the upper is still the original, its bored out to 50.

[Ratzkie]

I am sitting in the airbnb in NC after playing Fulda Gap the last two days, but I am almost done, for real this time!

Trigger grouping pin locations took me six or seven months to solve. Ended up sending the grip out for 3d scanning to validate my caliper measurements; I was a few thousandths of on most of them.... but it was enough that it didn't quite work.
Grip frame test #30 had the supports removed on the drive down, and I moved the internals into it last night. It works fine for the commission Eraser, but my Chaser doesn't seem to like it for some reason.I have an updated mag design that matches the grip aesthetic with grip grooves so its easier to pull out. I will sand the new mag (elephant's foot on the print) so it fits a little better and I can throw some rounds in it and take it to the garage- as long as I can get the trigger to work in the bored out chaser, this will happen asap.

Thanks for sticking with me on this project! Looking forward to having another worlds first in my hands! Attached is a photo of the CAD for the grip frame and the modeling of the DEagle body kit I made. A lot of this was done on stream, if you want to check my VODs on twitch, user name is the same as here.

[Ratzkie]

Good news friends. As well as confirming that I'm an idiot, I can confirm that the KT chaser, stock internals, no "speed" modifications, will shoot 50 cal fsr at "respectable" speeds on the absolute lowest setting with a stock-tipped bolt. That being said, I don't know what that is because all I can get from the chronograph is error 2 and 3. Which means that a dark garage at night, even directly under the light, doesn't have the ambient light needed for it to work.
I'm an idiot though and ruined several 3d printed test rounds because not only are they larger than .500 and don't fit in the barrel, I also neglected to cut the bolt back about a tenth of an inch to make everything feed properly. I started dropping paint down the barrel instead.

SO. Better testing tomorrow. I will cut the bolt, sand out the breech just slightly, and try more paint tomorrow. I fired 4 paint rounds numerous times and none of them have cracked or broken. So far so good. Time to turn up the speed (and hopefully chrono them).

I said it before, and I'll say it again more like two years later, Welcome to the Age of Semi-auto 50 Cal.

[Trbo323]

O used to have one of these, I was curious what it would take to make it 50cal.

So are you going to be selling these? As a kit or whole markers? I might be interested if you are

Sent from my motorola edge 5G UW (2021) using Tapatalk

[Ratzkie]

Still havent gotten home in time before sundown to test. I'm going to throw some spare LED lights in the garage, since most of the tubes are esd anyway.

That said, I'm dropping this project after I complete this one. Mostly because of cost. I can not find a printer willing to make "gun like" parts in sls nylon cheap enough to make this project work out. I found a new supplier, cheapest in the world at the time on the crowd source website, but they already canceled one order for paintball parts.
To make a kit and sell it would end up being close to $400, including a nebulous and probably low $50 charge to send me your body and ream it out. In addition, the brass detent screws have to be shortened by hand unless I ordered custom made screws and I'm just not going to dive into this project that far. I destroyed one already just trying to figure out how to grip it.

BUT. I'm not leaving you in the dark. I have been working on another project with the help of several known and established paintball manufacturers, enthusiasts, and legends in the community. I look forward to being able to officially announce that in the next 6 months. Current goal is to have the first prototypes ready for next play season... Potentially I will be testing one by or at Zero Hour Rebooted up in NY.
Also come play ZHR, ride the Blue wave to victory! Do your part to put Red Team down a second year in a row, regardless of how they prop it up with traitors and canadians!