Inner barrel length for an AeG

[Burger]

Where is the Jury on the best inner barrel length for an AeG right now?

I'm asking performance-related meaning which length of barrel will provide the best accuracy, range and manuverability ratio. Any information would be helpful, thank you.

I'm planning on using an AR-15 style rifle.

I've already looked it up on Google and other places, I'm simply asking for more opinions.

[Ricochet]

After the BB stabilizes, more barrel length doesn't have a large effect. It may bring your FPS slightly up or down, but also runs the risk of fouling faster if it's longer, so shorter is technically better. For that reason CQB length gives you the most maneuverability.

Before you go lopping your barrel off though, you want to make sure your hop-up is all that. Find someone who can do a proper R-hop, or flat-hop, and you'll be set. Longer contact with the hop-up mixed with good quality BBs is magic.

So with the hop-up out of the way you can worry more about barrel quality versus length. If recommend a Prometheus stainless steel, fluted barrel, in the 6.03mm to 6.05mm range. Too tight and you're BBs may go unpredictable and you're adding FPS, too wide and you're only increasing the spring strength/FPS needed to provide a stable cushion, which increase stress on your gun.

With a solid hop-up and high quality short barrel, you can then focus on compact maneuverability and it leaves room to add a suppressor as an actual tool of silence, versus a barrel shroud technique.

[Burger]

Originally Posted by Ricochet

After the BB stabilizes, more barrel length doesn't have a large effect. It may bring your FPS slightly up or down, but also runs the risk of fouling faster if it's longer, so shorter is technically better. For that reason CQB length gives you the most maneuverability.

Before you go lopping your barrel off though, you want to make sure your hop-up is all that. Find someone who can do a proper R-hop, or flat-hop, and you'll be set. Longer contact with the hop-up mixed with good quality BBs is magic.

So with the hop-up out of the way you can worry more about barrel quality versus length. If recommend a Prometheus stainless steel, fluted barrel, in the 6.03mm to 6.05mm range. Too tight and you're BBs may go unpredictable and you're adding FPS, too wide and you're only increasing the spring strength/FPS needed to provide a stable cushion, which increase stress on your gun.

With a solid hop-up and high quality short barrel, you can then focus on compact maneuverability and it leaves room to add a suppressor as an actual tool of silence, versus a barrel shroud technique.

Okay, you gave a lot of good information but you didn't give an approximate good barrel length you only said if it was too lon or too short there could be problems. . The reason I'm asking this question is to choose a completely new rifle. I will be using the rifle for medium to long range, it's intended to be a dmr-ish rifle.

[Ricochet]

If it's coming down to mm, who cares? Under 450mm, anything is adequate.

[devbro]

Very Very odd question.

Per my experience (which is not much) and all the readings I have done the length of the barrel has to match your piston air output. There is a hole/window on your pistol which is drilled based on the predetermined amount of air inside your barrel. notice that the longer your barrel, the more air it will have inside of it.

To have the best FPS and accuracy you need to go through this check list:
1. Match the air ratio of your piston to the desired length of your inner barrel.
2. use heavier bbs .25g should be good assuming you have to want longer range accuracy
3. check air seals around the piston and inside the hopup
4. use good bucking and hopup

Now to answer your question:
What inner barrel length gives best accuracy and performance?
The simple answer is: does not matter, the physiques behind shooting a BB is different than shooting a real bullet because of the shape of the projectile and the type of rotation they get during the flight.

on a real gun, the longer the barrel the more time you have to give the spin which allows for longer distance. On a airsoft it does not quite hold as the only part that changes the rotation of the bb is the hop up. the rest of the barrel simply works to achieve two goals allowing for the bb to stabalize and for more force to be applied to the bb. the more FPS you have the longer it take for bbs to stabalize but this distance does not increase as much as you expect it.

I suggest that you go for a tight 6.01 barrel instead of a longer one that should give you the performance that you want.

[ThunderCactus]

Tight bores dont help performance, they just foul faster.
Anything between 7" to 16" is fine. You could even go as short as 3" *i think* although hard to say, i havent seen any 400fps pistols with good hop setups shooting .30s.
But a pistol with a 3" barrel cant get a real tight grouping at 160ft, so its probably plenty accurate to 250ft.
Ive seen systema TW5s with 7" barrels get 1ft groupings at 250ft, my M14 does the same with a 12" barrel, and ive never seen a 650mm barrel with better results unless they were using heavier ammo.
So get whatever barrel length you want, prometheus 6.03 and pdi 6.05 are the best quality (which is all that actually matters; the finish). Get a flathop or rhop and run the heaviest ammo possible without losing range.

Theres no magic barrel length that optimizes everything.

[Ricochet]

Originally Posted by devbro

I suggest that you go for a tight 6.01 barrel instead of a longer one that should give you the performance that you want.

Hard disagree. Tight bore barrels will bring up your FPS a bit, but do nothing for overall accuracy. Balance between BB spin, distance and consistency equals hop-up, air stability and BB weight/quality. Don't bother with 0.25g, go 0.28g or higher. Basically you can go the 6.03 - 6.05 range or 6.1 - 6.2 range (which'll bring your FPS down).

[EOD Steve]

Originally Posted by ThunderCactus

Tight bores dont help performance, they just foul faster.
Anything between 7" to 16" is fine. You could even go as short as 3" *i think* although hard to say, i havent seen any 400fps pistols with good hop setups shooting .30s.
But a pistol with a 3" barrel cant get a real tight grouping at 160ft, so its probably plenty accurate to 250ft.
Ive seen systema TW5s with 7" barrels get 1ft groupings at 250ft, my M14 does the same with a 12" barrel, and ive never seen a 650mm barrel with better results unless they were using heavier ammo.
So get whatever barrel length you want, prometheus 6.03 and pdi 6.05 are the best quality (which is all that actually matters; the finish). Get a flathop or rhop and run the heaviest ammo possible without losing range.

Theres no magic barrel length that optimizes everything.

Have you fiddled with the PDI 6.08s yet?

[Ricochet]

6.08 was the old AEG standard; nothing special, but they should work with the right hop, BB, etc.

[Burger]

Originally Posted by Ricochet

6.08 was the old AEG standard; nothing special, but they should work with the right hop, BB, etc.

I just realized I've played with you before. I used to go by the name Iceman.

Do you do r-hop/ flat hop installs?

[Ricochet]

No, I don't. Yeah, we probably have.

Contact Damage - on here, he does a killer R-Hop.

[ThunderCactus]

Originally Posted by EOD Steve

Have you fiddled with the PDI 6.08s yet?

A few, unfortunately they're just a cheap cost-competitive line. The finish and windows on them are not very good.
From what i recall i think the madbull stainless barrels were nicer.
The PDI 6.05 is their accuracy line. Their 6.01s also have a great finish, but are specifically designed for raising fps. Used to say that somewhere on the PDI website.

[EOD Steve]

Originally Posted by ThunderCactus

A few, unfortunately they're just a cheap cost-competitive line. The finish and windows on them are not very good.
From what i recall i think the madbull stainless barrels were nicer.
The PDI 6.05 is their accuracy line. Their 6.01s also have a great finish, but are specifically designed for raising fps. Used to say that somewhere on the PDI website.

Interesting - are you sure you're not getting mixed up with their 6.1+ line?
http://www.x-fire.org/etop/1+.html

6.08:
http://www.x-fire.org/etop/08.html

6.05:
http://www.x-fire.org/etop/05.html

Side-by-side the 6.05 and 6.08 bore finish/window cut are similar/same. Price on the 6.08 is actually MORE than the 6.05.
I'm asking because I've gotten good results with the 6.08 but wasn't sure if my experience was a one-off.

[Burger]

Originally Posted by Ricochet

No, I don't. Yeah, we probably have.

Contact Damage - on here, he does a killer R-Hop.

That was my plan.

[ThunderCactus]

Maybe they changed the barrel since i looked at them?
But i had done 3 of them at once to rhop. All PDI barrels, all disappointing quality.