What relationship should there be between cannon and fps? In airsoft there were relationships between gun and fps, for example: if you had a 400mm gun you had to have more than 300 FPS but you couldn’t have more than 360 FPS because it was out of that range or the ball fell too soon due to lack of power or If you went overpowered, the balls went where they wanted since it had no precision, the longest barrel is placed for precision and not for distance, but there is something called the effective target distance, that is, you can reach 50 meters with your gel blaster (it’s an assumption), but the effective target is at 40 meters, so with the configuration between the cannon and fps of the replica and the hop up in this case that also comes into play, the effective target is sought to be between 40 and 50 meters, would anyone know about this in gel blaster?
In Airsoft they make up rules for different gats, for example they allow snipers to shoot higher joules limits than standard rifles or SMGs. Generally this offers snipers the option of using heavier BBs in combination with a little more velocity and hence they gain a range and accuracy advantage over regular rifles or SMGs (which without the rule limitations could also use heavier BBs or higher fps)
In gel ball, all gels weigh the same at 0.21grams give or take, so there’s no option for variety there in the rules.
Higher velocity like 400fps also doesn’t really add any further range in gel ball compared to say, 300fps, due to the limitations of firing a squishy ball of gel through the air and the effects of drag on that.
So overall I don’t think you can really apply these principles to gel ball. Also the maximum effective range for gel is around 30-40m.
I understand, but the length of the barrel will also make some kind of variation in the shot, right? this is where i wanted to go… is there any variation between a short barrel at 350fps to a long barrel at 350fps? more precision maybe? 
It’s all on the hop up I believe. A small SMG can be just as accurate as a sniper rifle in gelsoft. Meaning you’re better off with a automatic blaster. Spray and pray.
I have a 500 mm cannon on the way compared to the 300mm that the m16 has from the factory… I say that something will change 
and for the jump I have a Rizer… I still don’t know if it works or not 
A longer barrel achieving the same velocity as a shorter barrel, for example a 500mm and 350mm both firing 350fps should both perform around the same in accuracy. This isn’t a real sniper rifle where long barrels allow greater muzzle velocities for 2km kill shots.
With the same terminal velocity from the barrel, the range will be the same. As the barrels aren’t rifled and we use a round projectile, the barrel length (considering ideal setup) won’t make a lot of difference to accuracy. What will effect accuracy is:
- volumetric ratio: where the air pushed into the barrel being insufficient and creating a suction pressure (vacuum) with a non-ideal/solid projectile, creating spin or the volume of air pushed into the barrel is too much, creating turbulance at the end of the barrel and thus causing the gel to spin. Applying a longer barrel, without increasing airflow can reduce accuracy if the volumitric relationship was correct before. Could also lose fps due to the vacuum effect created.
- quality of gel: imperfect shapes of softer gels deform, creating a spin on the gel with non-uniform airflow past the gel.
- Hopup: controls the spin in a direction that creates lift called the Magnus effect. Backspin means the air travel on the bottom of the gel is moving faster on top, pushing the gel up. This will allow the gel to fly straighter until the gel slows down too much.
- quality of barrel: imperfections could cause resistance or effect air flow and put spin on the gel.
Going a very short barrel could possibly effect fps as there is less distance for the air pressure to be applied and therefore velocity could be lower, but you would have to have a very short barrel for that to make a lot of difference.
Now I have understood everything, a very explicit explanation, friend, a thousand and one thanks 
Agree with socialgamer. Was long posts in depth on old forum on this topic but that’s all toast now.
I use lengths from 180mm to 500m which are all very similar in accuracy and fps with VE setup to suit them.
Certainly agree with you there @Maiphut .
I mostly used to muck around with the M4 style blasters.
Barrel lengths were 220-500, but found the 330-350 with 7.3-7.5ID sizes respectively, the best accuracy/performance on a 100% cylinder.
The old rule of thumb of running gels .1 mm undersized to the barrel ID also gave best results.
Wasn’t until I got “influenced” by a few of the old members to delve into the SMG’s that I was surprised by the accuracy of the shorter barrels when tuned correctly…… definitely not any noticeable difference between short or long
Even if you ignore V/E, all of the gel blasters I’ve seen and handled shoot pretty similarly. The worst ones may shoot a 1.5m spread at 30M, while the best may shoot a slightly smaller 1m spread at 30M. Not a whole lot of difference in it especially when full autoing as most players do.
My experiences have been different. I had to work on the Azraels barn door AK to make it into a dinner plate as did many others as was posted. The XYL ARP 9 was fine as was the wells M4 CQB and MRT. Everyones experience differs meh
but dudes on the discord are saying their blasters easily do 50m accurately
makes me wonder how the bloke on the weekend wasn’t being hit when 6 of us were essentially mag dumping on him at 20m LOL
Those dudes saying easily doing 50m I would say may be plausible yeah, but if they say they are effectively hitting targets of a person size at 50m is for the most part is pointless bollocks. I will elaborate. 4 of my blasters are almost 380-390fps. All with everything possible done to increase consistency in shots (notice I did not say accuracy 
)
Beyond 40m, even if you have the “accuracy”, the target is going to see it coming and move, easily, out of the gels way and into cover. Leaving only targets that are not going to see it coming, which is the other side of my argument at this distance, the gel has lost so much energy that many people won’t feel it through light loose clothing, and won’t call it. So it kind of becomes a moot point to have the extra power and distance in the first place.
As Brad stated, 0.21g give or take, the joules are just not there to carry the gel much further than 40ish meters. My experience with 380-390fps blasters, they give very little extra distance than a 330ish fps blaster, and usually comes with a degree of lost “accuracy” due to gel deformation. I tune my blasters to a 1m x 0.5m sign, at 37m. With blasters 330fps and above I have no trouble reaching and hitting it most times with a reasonably flat trajectory, and a large amount of this comes from the hopup creating the magnus effect to carry the gel straighter and further. Is a 50m shot plausible. Yes. Feasible? Not really, it’sdebatable at best.
As for barrel length and accuracy, it doesn’t work that way. Correctly volumed a longer barrel can attain some extra fps due to more time accelerating in the barrel, while a shorter barrel requires more attention to volumes to reach the springs rated output, and avoiding excess turbulent air deviating the gel.
My experience is that 330-340fps is the best balance between usable distance and consistency (“accuracy”).
In short, they’re full of crap… got it. LOL
Yep, now you’re onto it 
For fun fact… finished building a well cqb today 
I know…
tested and tuned sights and hopup, hitting said 37m distance sign no troubles with nice accuracy.
The fun fact is that shortly after that due to the gels backspin keeping it travelling straighter and upward for longer, it basically slows within a few metres to a near stop, and drops to the ground. My 330-340fps blasters keep going a couple of metres further, but not much, and then the same effect. The 380fps blasters, maybe a couple metres more, then same thing.
Essentially, the gel just reaches a point where the air resistance and weight just cant carry it further. Also when used with enough hopup effect to more accurate, turns against your efforts to get distance and slows it down at a more faster rate at a point where the energy runs out. Gift and a curse. If you do want the 50m nonsense, you won’t have the accuracy provided by a hopup in full. In my experience anyway.