E&L AK Build (My Worst Idea This Year...)

Build ultimately came out as follows:
GATE Titan
SHS High Speed Gearset
Shim job
G&G Green Bucking

Literally everything else stock. Trigger response is wildly impressive (this is without pre-cocking) to the point that some people thought I was firing full auto when I was in semi.

The only hiccup (because there HAS to be one...) is that FPS is only at 345 with .2s. Currently, the gun has its stock spring (roughly M120 equivalent) which should be pulling higher than that, closer to 375 at least.

Definitely no leaks at the hop up unit. Before re-assembling the gun I made sure to check the cylinder and nozzle compression, both of which were good at the time. FPS is pretty consistent (only a 2 to 3 foot deviation) so I'm wondering if maybe the spring was soft from the factory. The one mistake I made was never chronoing the gun prior to modifying it.

For now though, it definitely works for field use. Eventually, I'll be taking it apart again to test for any compression issues. Assuming there are none, I'll definitely be upgrading the spring. 380 FPS is the sweet spot for me.

In the mean time though, it's just nice to enjoy a custom gun that works. It's truly a rarity for me.

 

After a lot of messing around, FPS issue is still present.

For a brief period of time, the FPS dropped to 300 with .2s. I've since removed the delayer chip and the FPS is back up to 340. Feeding still works fine. This could indicate that the nozzle movement is not synchronized with the piston, though I'm hard pressed to confirm this since I'm not feeling any air come out of the feed tube.

Changed out the spring with a Krytac stock spring which should give me 375 FPS. FPS still sits at 340 though.

Barrel is stock E&L.

As always, can't find any leaks. Not really sure where things could be getting bound up though.

To quote another thread on this forum, "resist the urge to just upgrade the spring," so I am trying to focus down the source of the FPS loss. I'm just out of ideas.

Might still upgrade the spring though... the gun cycles so fast that it "double shoots" in semi. I think a tougher spring would negate that problem.

 

16" barrel, stock E&L. (I've read that it's a tight bore, can't confirm.)

Started looking at the cylinder, and dang, no ports. Cylinder + cylinder head are one piece.

I'm surprised by this because my other E&L (stock, no modifications) shoots hotter and presumably has the same internals.

I have another spare cylinder + cylinder head that is ported (port ends 1" from the end.) Guess I'll try installing that and see if it helps with FPS.

Only issue that could remain is the double shooting in semi. I must admit, the stock E&L motor is quite strong.

 

Just to confi

Just to confirm:



The top one is a type 2 and the bottom one is a type 1, correct?

...and a type 1 would be best suited for a ~400mm barrel?

My spare cylinder head is currently mated with the top one and I can't get it out...

 

Lonex Type 1 cylinder installed.

FPS still at 340.

I think I'm about ready to give up on this project. There comes a point of diminishing returns.