UltimateInline MarkII

-Caliber: 6mm (airsoft)
-Magazine: 2200 rounds, quick reloading through detaching rear via cam-locks
-Barrel: ~12" Madbull Tightbore
-Velocity: ~410-430 FPS with .25g BBs
-Rate of fire: 115RPS at 130 PSI CO2
-Gas consumption: ~25-30k rounds per 5lb CO2 bottle

After making the original UltimateInline and using it on the airsoft field with much success, it earned quite a few nicknames, such as The Zipper, the Fire Hose, Blooper, and most popularly, The Flame-Thrower.

Every game or so I'd modify the gun in some way, adding different barrels and shrouds, different paint jobs depending on climate, etc, but nothing fundamental about the gun changed. This particular model, the Mark II, is a significant enough deviation from the original to warrant it's own page.

With the theme of a Flame-Thrower in mind, I set out to aesthetically enhance the gun, especially the front end encasing the barrel. Using ABS both to decrease weight and to eliminate the possibility of exposing white plastic if the gun was scratched by brush during use (as it frequently is), I essentially extended the perforated barrel shroud to about 9". The primary outer barrel, made out of 1" PVC pipe, is centered inside the 2" by means of a 3/8" thick disc of PVC rod with a 1" hole bored in the center. The actual inner barrel, in turn, is centered in the muzzle of the 1" pipe with a short piece of PVC rod and held in place by friction.

Next came the chamber and fire control. I liked the previous pistol-grip style blowgun, but it was thin and didn't have a safety device, not to mention kinda ugly. I decided to try out a pressure washer handle, and I was really impressed. Not only does it look and work better, it has a flip-down piece of plastic that blocks accidental firing, functionally working as a very solid safety!

Finally, the rear stock. As with the original UltimateInline, the rear stock houses a long spring which is attached to a plunger made from plastic rod, all thread steel, and washers. This plunger continuously feeds BBs into the vortex, making uninterrupted fire from any angle possible (a feat unique to the UltimateInline series!). To improve the stock, I replaced the 2" female cam lock fitting with a 2" plug, which I then bored out for the 1" pipe to slide through. You can see on the top picture where the black paint scraped off a little from the plug, leaving the white underneath. 1" couplings turned down on my lathe made excellent spacers to make up the gap between the 1" inner and 1.5" outer pipe (made from ABS). The 1.5" pipe was connected over-under style to provide a more firearm-like connection to the shoulder.

As for the little things... The neat doodads near the muzzle of the gun were made from 1" couplings spun on my lathe, and the "teeth" on the faux muzzle brake were cut using a small triagle file. I based the idea for the muzzle brake loosely from the ones I've seen on Tromix shotguns. Those sure are pretty, huh?

The holes in the shroud were cut using a spade bit, though if you wish to copy the pattern I suggest using a forstner or similar bit, as the spade bit has too much "play" and can leave the holes somewhat jagged if you're not really careful. A Weaver type rail was installed underneath the 2" pipe, and a vertical grip was attached for a more comfortable hand position.

Enough chit-chat! Here are the pictures: <-(video coming soon!)

The whole gun, from the front <-- screwy camera stuff makes the gun look bent or distorted... thats not the gun's fault ;-)

The barrel shroud

closeup on the outer barrel and muzzle

The BB count slit

The Backpack from the front

The Backpack from the rear. Notice how much back and shoulder support the pack has. These supports help alleviate the weight of the CO2 tank, and make it possible to pretty much jog all day with little discomfort. There is also a solid plastic backing which keeps the pack rigid and helps tremendously.

These hydration system holes in the top of the pack are perfect for the pressure gas hose.

When opened up, the main pouch of the backpack easily holds the CO2 tank, regulator, as well as any other things you'd like to keep in there. I carry 10k BBs, a crescent wrench, first aid kit, gloves, and of course, my lunch and a couple water bottles. If it wasn't for all the adrenaline in my system, I'd probably get more tired, but at the moment it doesn't feel that bad.

A total of 4 straps hold the CO2 bottle in place, so even when running it doesn't move around too much. In the picture, you see the two horizontal ones, but two straps also run up and down the pack and add extra support.

My normal loadout minus the flame thrower. The P90 is a backup gun in case I get stuck in a firefight between mag changes with the flame thrower. The P90 is upgraded to shoot 430FPS with .25s at 14 rounds per second. Carried at my right side one a 3 point sling, it is easy to grab and shoot if I'm caught in a sticky situation, and so far it has served me really well. I carry 3 hicap mags with me, 1 in the gun and 2 on the belt. The best part about this gun is that it can be easily fired with one hand.

And a couple pictures from my cell phone after playing with it on Sunday, March 11th:
Right side
Left side
-The paracord you see on the rear of the chamber was part of a 1 point sling attachment.
-I'll also have more pictures coming up soon showing my entire backpack rig as well as my other airsoft gear.

Want the UI MkII as a cool desktop background?
Here's a great "glowing edges" version in 1200x1024!

A video WILL be put up in the next day or two.

all images, text, and other content copyright 2006 John Shell, John@NeoSpud.com