Airsoft Sniper Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
150 Posts
Discussion Starter · #1 ·
I'm currently using a pdi 6.05 303mm barrel in my gspec with the mancraft sdik on co2

Fps is set at around 459/460 fps but would like to be able to up it to 480fps.

On 0.20g I get 1.99 joules and on a .40g I get 2.26 joules using an x3200.

I want to eliminate this jump in joule if possible and I think the only way will be a longer barrel?

Been looking into joule creep, but not much I could find out there says how to counter it however after seeing someone else's results in the mancraft thread it seems a longer barrel whilst still shows JC happening, isn't any where near as much as mine
 

·
Registered
Joined
·
236 Posts
Can I ask why you want to counter it?

Yes, a longer barrel will counter JC but also will up your fps and ,depending on length, will affect your accuracy.
 

·
Registered
Joined
·
150 Posts
Discussion Starter · #3 · (Edited)
Upping fps won't be an issue as I can regulate the co2 to accommodate any increase caused by barrel. Max length would be 430mm so accuracy will either suffer or improve over the 303mm

However I just realised I never tested what the joule would be on a .40g with the gun firing nearer 500fps on a .2

However with a jump from 1.99 to 2.26 at 459/460 fps I kind of imagine there will be a similar jump if I was to use .40s at 500fps on .20s, meaning I could be hitting a lot harder which I don't want
 

·
Super Moderator
Joined
·
3,784 Posts
There is no way to counter joule creep as it is a natural phenomena. The only way is to chrono in joules and not FPS. Only way I know how to counter it.
 
  • Like
Reactions: shortylumber

·
Registered
Joined
·
150 Posts
Discussion Starter · #5 ·
I suppose I chose the wrong wording perhaps.

Just after a way to negate the amount of joule creep, and it seems a longer barrel could solve it but my knowledge of it is poor at best compared to others who use this forum.

Quite agree about the need to chrono in joules though after testing mine
 

·
Registered
Joined
·
322 Posts
Uhmm, i might be wrong but, wouldnt making the barrel SHORTER counter the creeping?
The less time the bb is in contact with energy, the less energy it will absorb no?
 

·
Super Moderator
Joined
·
3,784 Posts
edit: what Cuervo said.

It would if you were using a spring rifle, but HPA rifles are different. Generally with gas rifles the longer your barrel the more time the bb has to accelerate. I do not have any direct experience with the mancraft, but odds are good that it follows the same rules.

I might pick one up in the future. Dunno yet.
 

·
Registered
Joined
·
150 Posts
Discussion Starter · #8 ·
Yep read about short barrels but it was only for spring rifles mainly.

They seem to have the opposite effect on gas guns, atleast from my experience anyway.
Would you say the diameter of the barrel would do anything to lower it if I increased from 6.05 to 6.08 but kept the 303mm length?
 

·
Super Moderator
Joined
·
3,784 Posts
It might a little bit but not the amount you are looking for.
 

·
Registered
Joined
·
150 Posts
Discussion Starter · #10 ·
Longer barrel it seems to be then I think. Thank you for the help in confirming what I had a thought on. Now to buy a new inner barrel and probably new rifle bag
 
1 - 10 of 10 Posts
Top