Mid-Handle, 2+ Band Blue-Water Roller Build

[Grizzlestomp]

Having shot a friend's Alemmanni down in Mexico, I've decided to build a massive roller gun. Unfortunately, I have a lot of gaps in my knowledge of the required details to get things perfect.

I plan to build a monster. 70-72", mid-handle, 11/64" shaft, 2 5/8 bands (with at least one of the bands doubled on the bottom of the gun). Super heavy barrel to try and get the recoil as close to zero as possible.

Before I get out my graph paper and engineer this badboy, I need to assemble the hardware.

Is there any consensus out there as to the best rollers for heavy-load, 5/8" bands?

The few I've seen so far are (1) the MannySub rollers with glass/nylon bearings and (2) the Stainless Steel Meandros bearings and rollers.

Any and all feedback is greatly appreciated.

Once I get the rollers, measure the diameter, and plot out where the bands will sit on the top and bottom of the gun, I can figure out how to shape/taper the barrel.

I was also wondering if anyone used different sized rollers (i.e. smaller diameter rollers on the outside of the gun) so that the bands could more closely lay flat against a heavily tapered barrel (see pictures below where the different size rollers would seem to enable a much more tapered barrel without a gap between the band and the barrel).

[cksea]

i have used the ronstan RF1766 roller sucessfully. Anyone have a source for 2.2mm pulleys for inverted roller guns or the small pulleys for compound(?) rollers, where you have multiple bands on the bottom.

[Castronova]

Have you considered why Alemanni only makes up to a 135cm? I don't know all the reasons but I'm sure loading is the primary. I'm certainly not trying to discourage you but when arguably the best roller gun builder in the world stops at 135 it seems like a huge endeavor to increase that by 35%.

Good luck to you either way. Is your friend in Mex. David V.?

[Wood Guy]

Originally Posted by cksea

i have used the ronstan RF1766 roller sucessfully. Anyone have a source for 2.2mm pulleys for inverted roller guns or the small pulleys for compound(?) rollers, where you have multiple bands on the bottom.

I can provide you with a set of 2 custom solid delrin rollers made to your specs for $32 delivered anywhere in US. Additional roller sets (they don't have to be the same as the first set) are $25 if shipped in the same box. These are custom machined to your specs, so you can design the rollers for the gun, not the other way around. There are over 400 sets of my rollers on guns out there - they work!

[phil herranen]

Originally Posted by Wood Guy

I can provide you with a set of 2 custom solid delrin rollers made to your specs for $32 delivered anywhere in US. Additional roller sets (they don't have to be the same as the first set) are $25 if shipped in the same box. These are custom machined to your specs, so you can design the rollers for the gun, not the other way around. There are over 400 sets of my rollers on guns out there - they work!

For hunting I prefer solid rollers like wood guy makes over rollers with bearings, the bearing rollers are loud and spook fish

[Fox55]

I've only Built to rollers so I'm no Pro but my 45 inch with a 5/8 bands is blowing clean through carp at 15 feet I don't think I'd want to shoot anything over 55 that'd be a tough stretch. And I put a little more meat around high rollers

[Grizzlestomp]

Originally Posted by Castronova

Have you considered why Alemanni only makes up to a 135cm? I don't know all the reasons but I'm sure loading is the primary. I'm certainly not trying to discourage you but when arguably the best roller gun builder in the world stops at 135 it seems like a huge endeavor to increase that by 35%.

Good luck to you either way. Is your friend in Mex. David V.?

- Yeah, I'm sure I have a lot of engineering to do regarding loading/band configuration. However, I would bet that the 135cm max length is because of the rear handle design of Alemannis, and also the fact that that length already yields a good 20+ foot range. There's a lot more leverage to push a larger mid-handle through the water, and the distance between your hand and your face when extended is just a waste (in my opinion, not trying to start up the age-old debate!) in the rear-handles. I feel like there are a lot of options out there with compound/split bottom bands, rest tabs, etc to make my plan feasible.

I'm still at the very early stage. I will keep the gun a midhandle, but may shorten it to 64-70". I built a 70" 5 band traditional gun, and was able to land a bunch of skittish wahoo at 25+ feet, and am a big fan of long range guns for blue-water hunting. I want a similar build, but with rollers for reduced recoil and a clearer line of sight. I know "its the diver not the gun", but sometimes fish just don't wanna come in on ya.

[Grizzlestomp]

Originally Posted by phil herranen

For hunting I prefer solid rollers like wood guy makes over rollers with bearings, the bearing rollers are loud and spook fish

-Huh, never thought of that. Thanks. Woodguy, I may take you up on that, though I still have a lot of designing left to do.

Is there any significant loss of power due to the increase friction? I figure the bearing rollers would only really make loud noises when loaded and fired. And since firing a blue water gun anywhere near a fish usually spooks it in the first place, I didn't take that into consideration. Appreciate the insight, definitely something to consider.

Down the line, I'm planning on building a much smaller roller for local SoCal Kelp YT, WSB hunting, and will definitely use solid rollers on that gun as a single fart can scare every WSB out of a kelp paddy.

[phil herranen]

Are you planing on both bands being two stage ,or pulley s?

I would do 2x 2 stage , and you will have to tune in the band's and shaft , from my experience 2x 5/8 two stage bands will be way too much power for a 11/32 shaft and maybe even a 3/8" , you need to tune it to where the shaft is pushed all the way to the muzzle . I normally start under powered and keep adding power until penetration starts dropping back down , then I do the same thing with a thicker shaft ,until I find the best combo

[Grizzlestomp]

Originally Posted by phil herranen

Are you planing on both bands being two stage ,or pulley s?

I would do 2x 2 stage , and you will have to tune in the band's and shaft , from my experience 2x 5/8 two stage bands will be way too much power for a 11/32 shaft and maybe even a 3/8" , you need to tune it to where the shaft is pushed all the way to the muzzle . I normally start under powered and keep adding power until penetration starts dropping back down , then I do the same thing with a thicker shaft ,until I find the best combo

I was leaning towards 2x2 stage bands. Or maybe 1 normal roller/1 two-stage band. Thanks for the idea on how to tune. I didn't know that penetration would drop down when a shaft was over-powered, though it makes sense that the shaft whip/flex would result in a loss of power. I guess I could use 2x2 stage bands, cut them overly long (300% stretch) and then cut them down and increase the stretch until I find the sweet spot.

Originally I thought about pulleys, but I'm not sure I can get the math right with a midhandle, i.e. can i move the pulley enough to ensure the shaft is pushed all the way to the muzzle with only the room in front of the trigger guard. By my calculations (granted, I have zero experience doing this math), I'd need the pulley to move a full 34" or so to push a 70" shaft all the way to the muzzle, which would likely not be feasible to do with only 50 or so inches of room in front of the trigger guard on a mid-handle.

[Grizzlestomp]

If a shaft is over powered (i.e. 2x2 stage bands cut at full 350% stretch), would an enclosed track stop the flex causing the decrease in velocity/penetration?

This shit is fascinating, I wish I had a full size swimming pool and high-tech underwater camera for lab-like testing.

[phil herranen]

I don't think a non 2 stage roller is loadable on that size of a gun , I have a 70" 2 stage that is 90% done and it is borderline Wether it will be a pain to load or not .

If it's a 2 stage don't use muzzle ramps they are not needed and are the cause of the low shooting problem most rollers have , someone started using them and everyone else just copied them without thinking about why. Even on a single stage they are not really needed .

On a 2 stage a bottom line release it important also otherwise you have lines crossing over where you are loading the second stage , but with a bottom release you also need a cover over the first and second stage hooks , ( but it should be there anyway so the gun doesn't need to be flied to load the second stag )

[phil herranen]

Originally Posted by Grizzlestomp

If a shaft is over powered (i.e. 2x2 stage bands cut at full 350% stretch), would an enclosed track stop the flex causing the decrease in velocity/penetration?

This shit is fascinating, I wish I had a full size swimming pool and high-tech underwater camera for lab-like testing.

It's not overpowered that way , it's just our acceleratin the retraction speed of the band's and leaving them behind before the full power stroke is done

[Grizzlestomp]

Originally Posted by phil herranen

I don't think a non 2 stage roller is loadable on that size of a gun , I have a 70" 2 stage that is 90% done and it is borderline Wether it will be a pain to load or not .

If it's a 2 stage don't use muzzle ramps they are not needed and are the cause of the low shooting problem most rollers have , someone started using them and everyone else just copied them without thinking about why. Even on a single stage they are not really needed .

On a 2 stage a bottom line release it important also otherwise you have lines crossing over where you are loading the second stage , but with a bottom release you also need a cover over the first and second stage hooks , ( but it should be there anyway so the gun doesn't need to be flied to load the second stag )

Hmm. Makes sense. 2x2 stage rollers it is. However, I'm a little confused at the definition of a two stage roller is. My knowledge is limited to the Alemmanni I tried out. In the image below, the outer band is two stages, in that you disengage one of the split bottom bands, load the top band, and then reload the 2nd split bottom band. So there are 2 bands lying on top, and four bands on the bottom (two split from each top band).

I was planning on designing the line release based on this design. Maybe use an enclosed track, then run the line diagonally across/over the four bottom bands, then around a pin about halfway down the stock of the gun (stainless steel wedge) and then along the side of the gun to a side release like on the Neptonics tuna mech. That way you can grab the loose bottom bands which are already tucked under the shooting line, and then stretch them into place along the bottom hooks/slots without getting in the way of the shooting line (which is safely out of the way on the side of the gun at that point).

If you don't have a muzzle ramp, I'm guessing you would have to load both bands on the back sharkfin tab? Wouldn't the downward force of the wishbones pinch the shaft as they collapse on the track/stock at the site of the rollers? I guess there isn't really anything for them to hold on to that would actually slow the shaft down.

However it is kind of a bummer to be able to load both wishbones on only one sharkfin as the bands don't lay quite as flat (even with staggered length wishbones). However, I could see how the muzzle ramp could cause rollers to shoot low by raising the back of the shaft as the wishbone rides up the ramp.

I wonder if using those European style notches in a 11/32 or 3/8 shaft would allow for the bands to be loaded in separate places (and lie flat) but still forego the use of a muzzle ramp.

[phil herranen]

I will get back to this later , you don't know how to post pics off a phone do you, every time I try it won't do it .