Inverted Roller Build

[apeogre]

Super cool!

[Hahalua]

they don't have a picture of someone's jaw hitting the floor, but mine just did.
this looks like an awesome build. best of luck!

what is the length?

[Grizzlestomp]

I think it is about 57" or 58" from butt to tip. The real limiting factor for rollers is you have to be able to reach the wishbones with the butt of the gun anchored somewhere. This was the limit for me, and it will probably be a pain in the ass until I get the hang of it.

[Nix]

Any progress?? I've been thinking a lot about inverted rollers this week.

[Grizzlestomp]

Took a few tries, but I engineered an extended line release that still allows for a crisp, fluid trigger pull and will not hold up the release of the line. There are some physics to consider because the longer release acts as a lever turning on the pin and can pinch the mechanism in the Neptonics Tuna Trigger, disrupting the trigger pull.

Essentially, I engineered it so that the line release adds force at an angle to the mechanism, instead of butting up against it with purely horizontal force, and so it actually encourages the mechanism (is sear the right word?) to release the shaft.

[Grizzlestomp]

Next I laminated a few extra boards onto the sides of the blank. I want this gun to have a really fat backside and taper down to a narrow muzzle.

Unlike traditional guns, in my opinion at least, muzzle flip is much less of an issue for rollers and inverted rollers. Especially with a handle really high up and in-line with the shaft, the force is directed directly back into the hand/wrist/arm.

For that reason, my primary concern is adding mass to the gun anywhere, not spread out along the gun from butt to muzzle. For example, on traditional guns, it is helpful to have mass and wide dimensions near the muzzle because that helps reduce muzzle flip and deflecting the shafts low.

Here, my goal is to put the mass anywhere, which reduces felt recoil. And putting the mass as close to the butt of the gun is ideal in terms of hydrodynamics. It is much easier to move a large surface through the water at arm's length (i.e. the butt of the gun) than 5" away (i.e. the muzzle).

Also, although the gun will be really wide, it will also be very narrow in the vertical dimension; only a little more than 1". So it will be easy to swing from side to side, or tip on its axis to swing vertically.

[Grizzlestomp]

I cut the general outline of the final dimensions on my bandsaw. As you can see, the bulk of the mass is way back by the handle, which is why I developed that extra long line release.

I'll probably slim it down a little bit as I approach the final shaping, but want to keep this width and mass to try and get the felt recoil as low as possible.

[Behslayer]

This is turning out fantastic. I like the way you are using composites within the blank. Looking forward to the Handle area and the Skin. This gun has been very well thought out.

[Marco]

Looking awesome! If it shots straight would be a bomb!

[Grizzlestomp]

Started shaping the stock. Epoxied on some purpleheart. Will shape the handle next.

Drew some lines and engineering guideposts, then used the graphite toothed grinding wheel to shape. A company called "King Arthur Tools" makes these wheels and they attach to any angle grinder. It take a very subtle and careful touch to avoid gouges, but saves a ton of time. My first attempt to use it to shape the whole gun and I probably saved a month of routing, sanding, and hand toolsng to get all the curves I wanted.

Of course, still have to use the old trusty method of a piece of sandpaper stuck to a flat piece of wood to make sure the straight lines are straight and true up the form, but overall a huge timesaver.

Will post pics of the overall lines, etc, once I clean everything up.

[Behslayer]

Radical.

[deanmc]

Originally Posted by Grizzlestomp

A company called "King Arthur Tools" makes these wheels and they attach to any angle grinder.

I have a disc very much like that one made by Kutzall. Great tool!

This build is sick!!

https://kutzall.com

[apeogre]

Are you going to build a trigger guard into the wood or will you make a metal or cf one? This thing looks bad ass

[Grizzlestomp]

Guiding all of my decisions is my effort to get the handle and the angles of force as high as possible and parallel to the track.

I shaped the trigger guard/pocket and handle out of wood. I then laminate a bunch of strips of carbon fiber onto the interior of the trigger pocket. My instinctual engineering (the only type of engineering I know) suggests to me that a fair amount of force could pass through the trigger guard and handle when it is this high.

To enable my second finger to be as close as possible to my trigger finger (and avoid an awkward, splayed grip), I had to route a channel in the trigger guard to allow the trigger to depress. I'll post some pics once I clean everything up, sand, and finish the shaping, but really like how high my hand sits and how natural the grip is so far.

[Behslayer]

Looking Good. Very Good.