It seems we’ve got a bit of a theme going here with FX Crown projects. People seem to like them though, so we’ll keep going.
The problem de jour is the magazines. We’ve already touched on this with our FX Crown Single Shot Tray post. The long and short of it though is, at least with the Crown, if you use a single shot tray you’ll notice a lot fewer fliers and your groups will tighten up. Why? Obviously something about the magazine is damaging the pellets.
My hypothesis is that the damage is being done to the skirts. There are three reasons for this. First is obvious, the skirt is the most delicate part of the pellet. The second is that the skirts on JSB pellets is actually significantly larger diameter than the pellet head. This is done, presumably, to maximize gas seal. But, and here comes number three, FX magazines are designed and machined essentially in 2.5D, that is to say straight and square vertical walls. This means they are easy and fast for FX to manufacture on a 3 axis CNC milling machine, but it also means that as the magazine snickity-snacks from one index to the next, the pellets are being shoved around and stopped, not on their more robust heads, but on their delicate skirts. Obviously that isn’t a win.
First off, credit where it is due to rj2239 for being the inspiration for this project. I initially sank my teeth into this hearing the MISTAKEN assertion on the forums that a Crown magazine is just a mirrored Impact magazine. Let me dispel this myth now, they’re not. They are very very similar, but are not the same in just a few critical tolerances. This stands in contrast to the FX Dreamline which FX claims will use an identical magazine to the FX Crown. Hopefully then this project can benefit FX Dreamline buyers as well. Regardless, even though I only used rj2239’s follower (and may still redesign that), the half dozen clever little fixes and small parts links were all invaluable to getting this done. So kudos and thank you.
So what did I change? Well the concept is quite simple: if the skirts are wider than the heads, provide clearance in the magazine for the skirts. This way the pellets are pushed around by their heads not their skirts. Aside from building the mag to Crown dimensions rather than Impact dimensions, the other minor change I made was to the support structure for the alignment slot. I’m not sure what printing technology, or clean-up methodology, rj2239 was using, however when printing his designs I essentially gave up cleaning that out by hand and started cutting the slots with a mill. Most people don’t have access to those sorts of tools, so a simple rethink of the supports in that area so it could be easily cleaned up with a fine knife such as a Scalpeldashi. (shameless plug, but it is what I used. I carry one for a reason.)
So by this point you’re asking how to get your hands on one of these magazines. We’re giving away the design files for free, so they can easily be 3D printed. Figure they’re worth what you paid for them, all humor intended. For those so inclined who want a transparent face cover, and don’t have access to a laser cutter, we’ll also sell you the raw cut acrylic face plates.
How to go about converting all this into a magazine, and what do you need?
Tools you’ll need at bare minimum:
3D Printer
Metric Hex Keys
Scalpel (or equivalent small sharp blade)
File
Needle Nose Pliers
Superglue
You would additionally benefit from/ideally own:
Quality ABS filament (as opposed to PLA)
Acrylic Face Plate (transparent)
Drill Press
Drill Index
Acetone
Hacksaw
Threadlocker
Squeeze clamp
Parts (all links go to Amazon for convenience, however they can be sourced anywhere):
M1.5x3 O-ring (3mmID, 1.5mmWD)
M3x5 Brass Insert
M3x3 Grub Screw
M3x10 Countersink Screw
2mm Brass Rod
Spring (from retractable badge)