A&K SR-25 Down on Power

[Flatteraxe]

Hello all,

 

I have various airsoft guns that have been in storage for about 18 months. I took them all out and chrono'd them yesterday and they all seem to be firing as they were before they were put away, except that is for my A&K SR-25.

 

It used to chromo at about 340fps but is now firing at 270fps. Maybe the spring was slightly compressed when it was put away and this has affected the power.

 

I want to change the spring to bring it back to 340fps +/-. I can't go over 350fps as this is obviously the limit that most sites set for automatic guns.

 

Does anyone know which spring I should buy for this?

 

Many Thanks for any help.

[Deva]

Stay on the safe side and put an M100/1J spring in there. It should give you roughly around 328fps.

 

Is the gun notably down on performance visually or are you only seeing the odd result on the chrono?

[Flatteraxe]

Hello,

 

Thanks for the reply. It seems as if it's all working ok but the bb's seem to take longer in the air, they sort of float now instead of being shot. I chrono'd it a few times and it started at 210 and kept getting better until it reached 270fps. This is down quite badly on what it used to be. I remember it shooting roughly 350fps out of the box.

 

Do I just need a standard M100 spring? I read that this gun has an extended gearbox or something, does that affect the spirng length?

 

Thanks.