SpudFiles

Even one inch should suffice.

And yes, the way I put it does make it sound like a contradition, of course the BB isn't magically held on a straight course without touching the sides of the barrel, but given the impact angles involved, a properly chamfered edge on the tighter section should give you no trouble at all.

@Jhalek, sorry, I missed your reply before, but that is a good idea. I'll see what I can do...
@Jack, thanks for the advice, if I cant get an airsoft barrel then I will have to do this.

As far as HP-LV vs. LP-HV, the fact is that with the HP-LV, you can get the same velocity with a lower overall volume of air.
Less air, less muzzle blast. Simple.

Gun Freak wrote:Here is the GGDT on 100 psi.

Helps if you click "calculate" BEFORE taking the screen shot.

jackssmirkingrevenge wrote:High pressure low volume is the way to go - you want the highest possible muzzle velocity to help with accuracy

Accuracy and muzzle velocity actually have very little relation - beyond of course when something is in the transonic range and loses stability as a result of the sonic shocks.

A good crossbow (300 fps) can shoot groups that could shame a 3000 fps rifle. I've seen airguns give firearms with over three times the muzzle velocity a run for their money.
Obviously, a higher velocity gives a flatter trajectory, but that alone doesn't make something accurate.

Personally, I'd say he should find some heavier bbs (such as .40g) and rein the velocity in. That will result in better accuracy than firing .20g BBs as fast as possible.
The heavier projectiles will also keep their velocity better and be less affected by wind.

Ragnarok wrote:Obviously, a higher velocity gives a flatter trajectory, but that alone doesn't make something accurate.

Fair point, consistency rather than velocity is the main point - but a fast projectile has less time to be affected by wind or gravity, which means the shooter has less compensation to make, and automatically it's easier to shoot accurately.

I vote on HP low Volume, normally sons better and more accurate. But by my experience, i won't suggest use -0.20g bbs, with high pressure some times them just totally fly away from trajectory. But 0.40g bbs are very good.

@JSR, does the "choke" on the end of the barrel really make the shot more powerful and accurate?

@Gun Freak, low volume high pressure for the win! shameless self promotion, but here's my airsoft gun that shoots well beyond what is safe to use in an airsoft battle, and it has a smaller volume than my shock pump.

P.S. JSR, you have an airsoft chrono right? how fast is an airsoft bb going to penetrate both sides of a soup tin?

Lockednloaded wrote:does the "choke" on the end of the barrel really make the shot more powerful and accurate?

It certainly helps with accuracy, indeed many air rifles have a choked barrel - and many an unsuspecting owner that went B-t-B on the barrel discovered that it has a very significant effect.

JSR, you have an airsoft chrono right? how fast is an airsoft bb going to penetrate both sides of a soup tin?

I have to buy a battery, I'll check tonight and let you know. What weight of BB?

.20g it barely made it through if that means anything

I have 0.25 and 0.12g BBs, I've give it a go with a 6mm launcher and cut the pressure until they barely make it through and see what sort of velocity I'm getting.

i agree with jhalek, but another option if you need a longer barrel, is to go to your local airsoft shop, usually when someone buys a tightbore barrel upgrade, the store keeps the stock barrel around, for a "just in case" they're not usually expensive and are usually pretty decent quality.

@Rag, sorry, I feel stupid lol. Anyway the result was like 880 fps.

Sounds like the definite way to go is HP/LV. I will have to look around for a good barrel, maybe if there is an airsoft shop nearby I can go over there and see...
I might be able to get some heavy bb's for testing but I don't think I will be using them in skirmishes, that would hurt too much.

please, please do yourself a favour and buy an easton X7 eclipse arrow shaft. It is the best airsoft barrel you can get if you can't get yourself a proper airsoft barrel.

lozz08 wrote:please, please do yourself a favour and buy an easton X7 eclipse arrow shaft.

Which one of the 11 sizes?

Please be more specific so somebody can understand why. For example;

An Easton aluminum 1714 X7 Eclipse arrow shaft makes a great barrel for 6mm airsoft bbs. It has a nominal ID of .2376 inches or 6.035 mm.

Another possible arrow shaft to use is a PSE Carbon Force 300. This carbon composite shaft has a nominal ID of .2440 inches or 6.198 mm.

Here is the thing, I need the bb to be able to roll down the barrel but it can't be too loose. It is a co-ax, so no breech loading. If I get a proper airsoft barrel, will the bb be able to roll down all the way relatively quickly, and also I don't think I will use an arrow shaft cause I'd have to go to like an archery store or something which I don't feel like doing just for a barrel.