Voluming Explanation (redo) 

yeah ive heard of people doing this

Elfren Authorlee PSG-1 has a 500mm barrel

Charlie Whelan 590mm*

I imagine there's a bore up kit but I don't know where you would find it. use the calculator for the optimal barrel length because idk what it is.

+Stev3419 Does it have to be that long? You might just install a shorter inner barrel. if the bb's are flying up you might have a hop up setup that is overhopping but I don't think the issues is caused by your air volume ratio.

+valleyriverarms The hop up adjustment doesn't do much with the 509mm barrel. it shoots perfectly straight with the stock barrel but the stock barrel is only about 300mm. If I use the 509mm barrel and I back the hop up off the slightest bit the the pellets go straight down after about 40-50 from leaving the barrel. I have sorbo pad in the cylinder for aoe correction so i loose quite a bit of volume in there. I've done the math and the cylinder to barrel ratio I have right now is around 1.6:1. The 2 people I know with dmrs have an air ratio around 1.9-2.1:1 but they are both sr25s with the longer cylinder but still have a 509mm barrel. I spent a good amount on buying my 509 mm stainless steel Prometheus type tightbore and have about $600 in the gun so I would like to use this barrel with the gearbox I've built up. If I do not get it straightened out anytime soon I might end up putting a polarstar Jack into it instead but as I stated would rather use the gearbox that I put the money into

+Stev3419 way too long of a barrel. get a 400-455mm. have one installed in my ak, much better accuracy

I've thought of trying some different angles and B roll but these videos take long enough for me to get my lazy ass around to making and uploading I feel like that would delay things even more. Right now I'm more concerned about getting the info out there. I do have some plans for some gameplay videos at some point though

you're supposed to roll the r a little and actually more pronounced than I usually do.

Hmm, interesting. Thanks for that little lesson

Depends on the company and the gun. Most of them probably not. It's pretty common to use a full cylinder in a lot of things.

So no port over 300mm and ported for anything under 300mm?

Oh you just said that

For anything longer than 400mm you want a full cylinder with no ports

Yeet 4K are you sure it’s not a gbbr

you might have too much oil in your gun too

probably a slight port but I would just do full and up your BB weight if you can

are your fps results lower than they should be? That's a better quantifier than range. Although that is a bit low. Check to make sure you're not losing fps in the bucking seal. Sorbo does compress but I'm not sure it would be that drastic. Possibly try different springs to rule out a soft spring.

well i actualy tried 3 buckings a lonex matrix and g&g same results. Its the hardest spring i got and my i think i allready told you but my friends guns used to be having around the same results but when we put in a full cylinder and then it worked fine it kinda just drops out of the barrel even though the hop up is turned all the way up (btw its a lonex M130) thanks but i dont thinks its the spring nor the bucking would you know any other ways?

Rau123 For good measure might try Madbull blue. They seal super tight. If your hop up is turned all the way up it might be too aggressive and is slowing the bb down depending on the shape of the bucking on the nub. I would still check for any obstructions and possibly try another spring to see if anything changes. A lot of this is going to be isolating problems.

valleyriverarms i guess it wont hurt to try but i am not convinced that it is the hopup but i should have told you before i did tried my friends hopup also that works in his gun great and the results were also the same he has a g&g hop up same as mine with A+ bucking and the same thing happened i was just thinking of this could it possibly be the delayer chip, or possibly barrel suck it also has a really low fps like 300fps but like what you said i will try an m120 see how that goes. btw thanks very much for responding i think your the only youtuber that has responded to every question i have asked.

ported one on the more aggressive side

updated

they "should" but most won't. Some event organizers are getting smarter though.

Angelos Tselios Teflon in cylinders just protects and "lubes" it. The piston goes smoothly in teflon cylinders. I have Deep Fire's teflon cylinder

When you read my long name, I stole your sandwich Yes, I just wanted your opinion if teflon its better to buy a teflon cylinder, or the best occasion to use them. Thanks !!!

i mean i can assume that way it would be the most accurate to match right? is there also something to say about the amount of compression that takes place by the speed and weight of the piston ?

sure yeah that would be the better option but that requires extra work most people don't wanna do

I think I explained in the video that I think bore up kits with a port in them are dumb. Because you're bleeding out the air volume you're trying to increase. Guarder airseal parts in general are pretty nice though.

Okay thanks. And have you ever had problems with the piston head?

Nope. Rarely use bore up though