[paladin68]

I just got the prototype back from the printer, and I wanted to share this build with everybody - I introduce what I call the Bullpup Mag-Fed .68, or BMF68:








I printed this in PETG to make sure my measurements and dimensions translated well, so there is a lot of stringing to clean up, but as an initial test-fit, it seems like everything is pretty darn close. I'll keep this updated as I continue to work on it.

[Mr. Charlie]

Looks awesome, nice work!

What marker is inside?

Share some more details!

[Paul77]

I think it’s ion based from the looks of picture 7

[Mr. Charlie]

^ Yeah I see that now, thanks!

I still want more details lol!

Bolt, barrel, other upgrades?!

[paladin68]

It is an Ion, gonna be full of upgrades, there is a Palmers Boulder reg built in, and I have a virtue board that will allow a bunch of trigger modes and FA ROF adjustability.
There were a lot of parameters that I want this marker to fill:
First, I always wanted a Bullpup PDR-style marker - I play in pretty tight places (corrugated drainage pipes, anyone?), and carbines (AR, etc) where the barrel starts where your support hand is leaves a LOT of barrel sticking out in front of me, bumping into stuff. I can get a full 14" barrel in this with only an inch or two protruding in front of my support hand.
It is based on a Smart Parts Ion because the engine is a fast, reliable spool-valve that runs at super low pressure (I have a Tavor build using an Ion, and it runs at less than 140PSI with first strikes), which makes it pretty damned quiet. There are also aftermarket boards that allow a lot of settings and control. Even with a stock board, you get a nice controllable full-auto of about 10bps, as well as 3-round burst, which is really a game-changer in my opinion.
Did I mention full-auto? Mouse-click trigger?
Then the overall design of the body takes into consideration all of my dream features for a paintball marker. I took pieces of all of my favorite Bullpup designs (Magpul PDR, Tavor, SRU, etc) and combined them into an 18" long minimalistic design that barely covers the mechanicals inside. It is also as slim as I could make it at 2.17", and the widest point is the pictinney rails on the sides, with the majority of the body only 1.75" wide. All of this should result in an incredibly light and maneuverable marker.
It also has ambidexterous forward-control, one-finger drop-free mag release and a huge flared magwell for lightning quick mag changes.
I used DMag Helix mags, and designed it to feed directly into the breech instead of having the gap that allows balls to drop out during mag changes. This shortens the overall design, and lets you shoot every ball in your magazine. I also used Helix mags because they're are only $15 each in case I drop one and can't find it, and hold a full 22 rds of roundball or 20 FSRs.
Anyway, more details and pics to come - back to sanding!

[KingSky]

Fantastic work! I love that's it's a bespoke design with obvious inspirations from some others, but very unique. Great work! That breach milling is beautifully clean, what did you use?

Also, on the forward mag release button, what did you use for the linkage?

I can't tell from the render, is the trigger a linkage or did you wire up a remote trigger switch?

And how many pieces did it print in?

Great work! Dunno if you're on Facebook, but there are some groups on there that would love this project. Custom Paintball Markers and 3d printing paintball and custom ion builders.

[ascendead]

Any updates to this project? I've done a few different bullpups over the years but don't have access to a 3d printer, let alone the time to CAD out a shell for one. Curious about how you worked the mag release as well, as that is always a talking point when it comes to making bullpups.