Tweaking FPS via barrel - Would this work?

[westywesty84]

Re: Tweaking FPS via barrel - Would this work?

There's not that much room between inner/outers to cause vented air to move the inner.... Maybe if there is...holes on either side will counter act against each other in terms of air pressure on the outside of the inner

[cannon_fodder]

Re: Tweaking FPS via barrel - Would this work?

I think it should work in theory on longer barrels.

However most inner barrels are a tight fit in the outer so probably wouldn't vent the air.

You could try several holes right next to the hop unit were the outer barrel is wider. This would also give you the most pronounced effect.

I don't think a precision hole in the barrel wall will affect accuracy OR consistency. As the hole wont change shape then the air escaping should be the same each shot and so by definition consistent.

I'd love to see your results

[bladerider]

Re: Tweaking FPS via barrel - Would this work?

Yes, but I'm talking about sealed gearboxes. Does an M249 gearbox fit in an AK or G36?

The more times you open them up, the closer your AEG gets to the pearly gates. Up/downgrading isn't simply a case of selecting an 'x' Joule spring and voila - bang-on as there are so many variables.

I was just suggesting this as a quick way to adjust to avoid the hell of break-down/open gearbox/change spring/close/reassemble/test/break-down/open gearbox/change spring/close/reassemble/test/...

Would a few micro holes really upset consistency (or accuracy) that much? An air leak is an air leak and if the hole is consistent then why not the air leak?

No they are specific to a 249 which sucks! We need more platforms which aint such a bitch to work on. The quick change spring is great, just press the button and the guide and spring pops out the back of the box.

Agreed on the 'more you open it bit' for a normal aeg being opened a lot wears out the soft alu or pot metal threads. Plus i think its a mental thing too, i start to hate anything that needs to be opened a lot. Anymore than 2 or 3 times in a few months and it gets fooked in a corner.

I'm no aerodynamisict but far as i remember the bb moves down the barrel in the middle of a 'bubble' of air as some of the air passes it before the bb starts to move and around it once it is moving due to the fit between both. Any deviation in the barrel bore will cause turbulence in the air pocket so the bb will bounce down the barrel giving poor accuracy.

I think it was the spitfire or possibly the hurricane iirc that it was discovered a difference in raised and flat rivets on the wings could give 7-10mph gain on top speed. Smooth is better!......Told you i know some useless crap!

This could be completely wrong as i read a lot of irrelevant crap but you have to ask why it has never been done given that we even have rifled barrels for airsoft. If you want to make your own you will have to start with a 6.01, drill it and hone the whole bore out to 6.02 or so as when removing the burrs from drilling the entire barrel will need to be refinished to regain a uniform surface. Again correct me if i'm wrong.

This will be a pretty expensive barrel if it did work which i doubt it would. Be nice to have a machine shop to test all thse ideas.

[r6shooter]

Re: Tweaking FPS via barrel - Would this work?

what about using the FPS reduction unit from tm

you add different coloured rings onto the unit and it abosorbs a certain amount of air into the rings reducing fps

and it screws onto the flash hider thread 14mm CCW

or you looking to keep the gun asthectically perfect externally

and would the hole drilling idea actually cause air to build up and unevenly ball around behind the bb

[Ells]

Re: Tweaking FPS via barrel - Would this work?

@r6 - they only work on semi and most sites dont accept fps tests whilst using them

@OP if the bb bounces down the barrel surely it could bounce onto the hole causing innacuracy? or if the bb travels in an air pocket as also theorised surely that'd upset the air pocket and cause inaccuracies?

have you considered putting holes in your air nozzel, - less likely to affect accuracy as its behind the bb, if you put a few holes in there and cover them up should be able get what you want?

[Ells]

Re: Tweaking FPS via barrel - Would this work?

hell you could probably even cnc a metal air nozzel with little hex bolts that go in to allow you to seal and open the vents easily?

[Phatvortex]

Re: Tweaking FPS via barrel - Would this work?

Why not drill holes in the cylinder? Most guns woud allow you to get to a grub screw or whatnot in/ out of there easily enough.

[L3w151988]

Re: Tweaking FPS via barrel - Would this work?

Here's another suggestion, what about that fairly recent SAT Variable Velocity Device?