Prototype Mako Roller Muzzle

[TBD]

I would like to take the time and introduce a prototype Roller Muzzle for the new Mako AR15 American ETR/Open speargun.

The main driving force for this design was simplicity. How simple could a roller muzzle be; machined, attached to the gun, rigged and operated. Having experience with other roller guns, both custom built and purchased, I was able to come up with a design that I felt addressed most if not all of those topics as a system, not individually.

The muzzle itself will accommodate all band sizes and does not require any tools to load. What is unique about this muzzle system is its double action pulley loading. At first it seems a little cumbersome and complicated, but once the band is loaded onto the sharkfin the pulley system on the underside of the gun gives the uses mechanical advantage to pull load the band to a very high stretch percentage. This idea was taken from Tin Man, when he was tinkering roller muzzles. See Thread http://www.spearboard.com/showthread.php?t=153545

Rigging was the next hurdle. Since Mako just released it's reverse mechanism trigger I thought I would be a great idea to move the line anchor from the bottom of the gun to the side of the barrel. This move made rigging the gun very easy. It moves the shooting line from crossing under the gun (over the second stage bands) and puts it in an easy to access spot on the barrel. In one of the images I used a simple bolt and jam nut due to being in a hurry to test it out. Testing proved very successful with no line tangles or rigging issues.

Overall the first prototype was proven very successful. Since testing it, I have since revised the muzzle and am currently waiting on machined parts. The goal of the second prototype is performance and accessories. The second prototype is represented in the 3D rendering.









-Joe Solomon

[hau]

These roller gun conversations remind me of back in 1968 when I was working with Hollas Allen and the very first prototype compound archery bows.
TBD--good luck with your work and let us know what your chronographed spear speeds are sir.

[Tommy T]

Joe,
I like the emphasis on simplicity...design looks user friendly. Looking forward to the progression of this design. Not sure what a chronographed spear speed is but I'd appreciate a video titled "Dummies guide to loading a roller gun"! Oh yeah, an ETR is unnecessary, yes & how long is your Mako AR15? Thx. T

[TBD]

Originally Posted by Tommy T

Joe,
I like the emphasis on simplicity...design looks user friendly. Looking forward to the progression of this design. Not sure what a chronographed spear speed is but I'd appreciate a video titled "Dummies guide to loading a roller gun"! Oh yeah, an ETR is unnecessary, yes & how long is your Mako AR15? Thx. T

"Dummies guide to loading a roller gun" is classic. The gun is 120cm with 191.5 cm of band stretch.

[Tommy T]

TBD,
I have a Mako 130 Oceanic ETR that'll start gathering dust once & pick up my new Mako AR15 ETR. Whadda think-convertable to the roller muzzle once you get it dialed in? Put me in line for one of your muzzles if it sounds doable. Thx bro. T
PS Going to need that vid for sure!

[warfrog]

It was really cool to see that gun in person yesterday. It's stuff like this (and the other gun projects I see people doing) that really make me wish that I had gone into engineering, rather than business. But hell, I'll just pay the extra $$ for a finished muzzle after you've hammered out all the bugs.



--Charlie

[TBD]

Thanks Charlie!

Here is a quick update for everyone. Just added a reel option to the gun, really simple adapter.

[fjpatrum]

Originally Posted by hau

These roller gun conversations remind me of back in 1968 when I was working with Hollas Allen and the very first prototype compound archery bows.
TBD--good luck with your work and let us know what your chronographed spear speeds are sir.

Interesting comment as I was just wondering the other day if anyone had considered cams like are used on modern bows as opposed to rollers. I'm new to the whole concept of spearguns but there seems to be a lot of room for moving in some very cool design directions.

[TBD]

The second prototype was machined today along with some new rollers. The second prototype addresses weight and overall performance.

[spearq8]

Do these rollers use any type of ball bearings?

[TBD]

No. These rollers just use an loose fit over the shaft. Ball bearings in the rollers can be a pain in the ___ because of what can get into them. I shore dive primarily and my guns are subjected to a lot of sand and debris. What's nice about ball bearings, if done correctly it gives you a can clamp up on the inner race of the bearing to make a tighter fitting muzzle.

[2fishin2]

nice work

[stevemc1]

Nice! Looks like the second muzzle will be higher to miss the sharkfins unlike the first version. Usually there is a bar to catch the wishbone. Very good way to do that. Simple, sleek and not bulky. I have noticed in the last few years nobody is doing the roller guns with levers under the gun how they were done years ago. Could really get some power. Pivot in the middle of the gun, catch the lower wishbone at front and crank it back to in front of the handle. Use a much shorter band and really stretch it. Use mechanical advantage. There is a catch that holds the lever.

[Wood Guy]

Originally Posted by stevemc1

Nice! Looks like the second muzzle will be higher to miss the sharkfins unlike the first version. Usually there is a bar to catch the wishbone. Very good way to do that. Simple, sleek and not bulky. I have noticed in the last few years nobody is doing the roller guns with levers under the gun how they were done years ago. Could really get some power. Pivot in the middle of the gun, catch the lower wishbone at front and crank it back to in front of the handle. Use a much shorter band and really stretch it. Use mechanical advantage. There is a catch that holds the lever.

You're right. I seem to be the only one whose built any in the last several years (2 lever action, 2 crank action). There are some reasons, however. They are more time consuming to build than a simple or "traditional" compound roller, though not more difficult than an inverted roller. You also give up the distance from the middle of the lever to the trigger guard. On a compound roller you can pull the band back that additional distance. You also give up the mechanical advantage if you want to shoot 2 bands. I like 'em a lot, and will undoubtedly build more, but they are not about to go mainstream. The thing I like most about them is that when the lever is forward the bands are really easy to grab to load the top, then you just move the lever back to load the bottom so you don't have to try to grab bands that are already pretty tight.

I've been designing a 40" lever action from either the green / onyx like I used for my grandson's gun, or the blue / onyx colored plywood that I've bought for the commemorative Gil Gun hybrid that Tin Man and I are building.

http://www.spearboard.com/showthread...ion+roller+gun

http://www.spearboard.com/showthread...27s+roller+gun

[TBD]

Thanks everyone for the kind words.

The depth of the track is the exact same as the previous one. I am able to get away with a deep open track do to the fact that this gun is a two stage roller.