Question regarding volumetric ratio

I’m using a 60% ported cylinder with 7.5 id and 23.5cm inner barrel. The accuracy is okay-ish when firing gel balls at about 30m without hop up.
If i change the cylinder from 60% to 70%, will my accuracy increase and the gel balls spread will decrease?
Thank you

That will give you a v/e ratio of 1.9 which, in theory, should reduce your accuracy. Accuracy with gelballs is pretty much witch craft once you are within the 1.65 to 1.8 v/e range.

My most accurate blaster at 30m is an old gen 8 modded Steyr, that will consistently produce a 1m wide pattern at 30m. Other blasters built to a similar spec generally fall within the clothesline width spec. The one that gets the most distance (just about 40m) has one of the shorter barrels, while the one built for distance only gets to 40m if I use goat balls.

Different brands, age, growing medium and growth rates of gel balls wildly impacts performance and accuracy, even with gels graded to the same size. Some gels (AKAs) will function adequately after 4 weeks in a sealed container, while others (eg Predators) are done after two weeks due to flat spots

Establishing a controlled environment to compare performance and accuracy is just about impossible, and I’ve sacrificed all the chickens we had available

@RokSolid can give you all the details. He probably has the most current experience

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Best I can say is to measure the “swept distance” of the piston, to the port. Because cylinder heads are all different, and not every ported cylinder is the same either.

Then plug it into this page:

Enter the swept distance into cylinder length
Then full out barrel diameter and length.
It’s a pretty accurate guide of volume for whatever application you are using.

Barrels 22cm and up are usually good with a 60-70% cylinder depending on how much cylinder head takes up… Aim for ratio of 1:1.7

275mm -290mm is usually an 80% cylinder.

Barrels under that I tend to try for ratio more around 1:1.5. short barrels can be pricks if aiming over 300fps, as the gel is leaving barrel before being completely accelerated to the springs potential. Some experimentation is required for cylinder volume and spring to get desired results, if only aiming for about 300fps usually will get how it works in reality though.

Barrels over 335mm, go a full cylinder. When going up to 40ish cm you will get a bit of extra fps over the springs rating.

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