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Rollerhead setup help?

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.
L

lawstraljan16

Active Member
Jul 9, 2012
445
63
43
Hi guys I've got myself a rollerhead from Alemanni, but have absolutely no idea how to set it up. I did get help from pro's but their setup for some reason didn't have the performance on mine that it did on theirs.

Could someone give me some tips on how to measure band length for a rollergun (stretch %)? What pre-tension I should have etc? I'm going to be using 16mm bands, and a 6.5mm spear. I also have a 7mm spear but I'll be testing on a 6.5mm for now.

Thanks
 
Anyone? I'm getting really annoyed that I can't seem to get any good results with my setups.

This sucks big time! I can't find any info online at all...
 
lawstraljan16 said:
Anyone? I'm getting really annoyed that I can't seem to get any good results with my setups.

This sucks big time! I can't find any info online at all...
Click to expand...

I'm not an expert on rollers, but I would use 14mm bands for the 6,5mm spear and 16mm bands for the 7mm spear. I would choose some very progressive bands like the amber coloured/amber coloured with thin coloured protection layer.

Most bands deliver their power best at a stretch ratio between 280-360%. So I would measure the longest distance from a shark fin on the spear to the anchor point on the other side of the rollers and gun. Then subtract the length of the wishbones/anchor line and divide the length with 2,8 (280% stretch). Remember to ad some cm for the constrictor. You can work your way up in stretch ratio from this point by cutting cm by cm of the bands and test how it performs. If you can't load the gun to begin with, I would go down in band diameter size. It's a compromise between power, accuracy and what is possible for you to load.
I never tried this method with a roller gun, but it works fine on a conventional band gun. I don't see why it wouldn't work with a roller.

You can experiment with the stretch of a given length of bands if you tie in a loop in the end of the bands for the anchor line or wishbone. This makes it easy to change the length of the line/wishbone from the bands to the anchor point.

Good luck,
Jegwan
 
Last edited:
@lawstraljan16,
Hi!
Welcome to the world of rollers!
Alemanni seem to be one of the most "established" rollers out there. So congrats on a new buy.
I havent used their rollers, but we made rollers ourselves. As far as I was concerned, pre-tension was not the most important bit. I will second Jegwan's post, its more of a "loaded-stretch" issue.
We used 16mm bands (single) with 7mm shaft, but my friend uses 16mm with 6,5mm shaft and it shoots lovely. Its more of a "give it a try" thing, really.
Just keep in mind that perception of power is very different with rollers. If u are used to 2/3 band guns, with a quite a recoil - then roller will feel underpowered at first. But again, you get used to it.
Trygons has been stating that <280% is a good stretch for 17mm+ bands, whilst <340% is ok for thinner bands. Somewhere around 300% will be pretty good for you, I guess.

Did u get the head only? Or you purchased the whole gun?
 

I only bought the rollerhead.

I'm having quite a bit of problems to be honest. The gun seems to be lifting upwards and the gun tips the rear if the shaft causing the shaft to drop downwards. Any idea? I can post a video of the gun shooting sideways (slow mo) so You can see whats happening.

Id appreciate the help since I cant find too much info on rollers or many people that have experience with them.
 
From what I understood (" The gun seems to be lifting upwards") the muzzle was much lighter then it had to be, thus causing the effect. Have u used additional weight to balance the gun? Another reason could be the shaft being too light (the "whip" effect). Or maybe the rubbers being cut way too short.
It would be pretty helpful if u could post some vids
 
Your problem reminds me of this video, the roller gun muzzle lifts during shooting tipping the spear downwards... Not ideal!

[ame=http://www.youtube.com/watch?v=urZepR073cs]Test Seatec Roller 100 e Geko 110 - YouTube[/ame]

Bit of a pointless post but at least it shows that muzzle lift happens to other rollers...
 
I think that it would be a good idea to experiment with different lengths of the wishbone/anchor line on the underside of the gun. This will move the position of the rubbers on the gun/rollers. I believe that this could (besides the balancing of the gun) have an influence on how the gun muzzle moves when shooting.​
 
Here is the video

[ame=http://www.youtube.com/watch?v=n2BHUa7dA6I]Alemanni rollerhead - test - YouTube[/ame]
 
Nice video.
It looks like the bands are to powerful for the spear in my opinion.
Jegwan
 
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