A&K SR25

My all time favorite weapon!

Bought through an airsoft flea market. I’m probably the third owner (at least). Each owner has added his charm to the weapon. This particular one was my main go to rifle for almost 3 years.

The weapon came with:

  • Nozzle alignment done (hight and side)
  • Lonex A2 high speed motor
  • Siegtek 27,5:1 gears
  • Old generation Prowin m4 chamber
  • Prometheus 509 mm, 6.03 mm diameter inner barrel with an IR patch in place (rubber unknown).
  • SHS Nozzle, SHS cylinder head stock cylinder (Bore up long cylinder) and SHS piston head.
  • Home made mosfet
  • Weapon run by a 1300 mAh 7,4 v lipo.


  • Stock “M16” stock
  • Real Magpul Pistol grip
  • The gun came with 4 Magpul LR20 mags (Sr25). These are nowadays priceless (have not been manufactured for years).

Changes that I made during a time period of 2 – 3 years:

  • First had to remove the IR patch, it was damaged (hopped slightly to the side)
  • Flatted it with the Prometheus lilac flat modded rubber, worked excellent. (used for over 1 year)
  • Later IR patched it again (recently) used the same rubber as seal, works way better (with less hop, more output velocity)
  • Mosfet removed and the ASCU for v2 gen 3 put in (due to manufacturing problem, the mosfet fried)
  • ASCU changed to a Gen 4, worked excellent.
  • Gears changed to SHS reinforced SR25 gears 16:1
  • Motor changed to SHS High Torque motor
  • Corrected AoE with a large sorbo piece (6 mm)
  • Changed the piston to a full metal teeth SHS reinforced long piston, corrected it for Aoe (removed 1 tooth)
  • Started running the weapon on a 1200 mAh 11.1 lipo battery


  • Got a BSA Contender 3 – 9 x 40 mm sight laying around
  • Changed the stock stock to a buffer tube with a real Magpul STR stock
  • Found 2 more Magpul LR20 mags on a flee market (cost was unbelievable)

A DMR in Finland, back then where allowed to fire 2.25 J max. That is 150 M/s on 0.20 g bbs. That corresponds to 492 FPS on 0.20 g bbs. I achieved this with a M130 SHS spring (2.20 – 2.22 J).

Nowadays some fields allow 2.5 J, thats 519 FPS or 158 m/s in Finland.

Berget events allows for 140 m/s, that again is 1.96 J (459 FPS), achieved this with an SHS M125 spring.

This build is effective for 60 – 75 m about when tweaking the hop-up mid game. In Finland we are not allowed to use plastic bbs in our fields. This restricted me to just a couple of different heavy bbs. G&G 0.28 g bio bbs worked well, but got fire a little too high velocity. The effective range was not that good. Later found Green Devils 0.30 g, these worked excellent. Also tried G&G’s heavy 0.33 g bio bbs. These were rubbish. The quality control was not there, tolerance was unbelievable. I later found longbow 0,30 g bio bbs, these work excellent. As goes for Longbow 0,32 and 0,36 g bio bbs. The heavier the more precision you get but also less shot to target time, which in some occasions can be crucial.

This has now been boxed, since I’ve shifted to the SR25k as a main weapon.

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