In that case all 5 of my springs would have to be mislabelled by 20. The spring netted me 380 fps when the internals were stock, but after a lot of fine tuning I was able to net 455 fps.

Modify did some testing on their own springs. I'm pretty sure their gun simply has a good air seal, as opposed to inflating velocities with stiffer springs. I've always found their spring ratings to be consistent with MadBull, SHS, Element and CA.
http://www.airsoftparts.ca/news/modifyspringtest.pdf

it was my g36 that had a 407mm prommy eg and it originally came with a cylinder for 247mm. I think this is the one I had to glue the 3/16th + neo directly onto the rubber pad to get my desired aoe.

You do know that the spring designations are standardized to tell end-users the desired m/s velocity out of that spring with 0.2g right?
M120 = 120m/s = 393fps. It was only with the introduction of bearing spring guides that the FPS got a boost up to slightly over 400fps.

Why Modify decided to make a "S120+" spring shoot 444fps, is completely beyond me.

I've wanted to do this too. I managed with random junk parts to get a negitive creep with an under volumed cylinder. Was shooting ~1.1j with 0.25,0.28, 0.30 & 0.36 bbs but with 0.20's it was shooting ~1.5j.

Edit:

Forgot to put in the spring was an m100.

Don't forget bearings on the Piston Head as well. Everything accounted for you're getting a good half inch of pre-compression on the spring. Add a 3/16" sorbo as well for even more pre-compression.

I remember reading somewhere SP and M ratings were different. SP ratings were higher than M? Logically it doesn't make any sense why people would do such a thing. :banghead:


I ran a thought process build in my head for this.
.32g ammo
247mm barrel
Full Cylinder
Lonex M130 spring
Lonex Red with 3 teeth SS
Lonex Aluminum Head with Bearings (cause you want a heavier mass)
13:1 or 18:1 gears (if ferrite motor go 13:1. if neo motor go 18:1)

Should be able to hit 400fps equivalent on a .32. Switch to 0.20 ammo and hopefully it's only 350, which would be good for CQB.

John

I think that the setup was standardized on a stock "Marui" setup. As you would know, there are lots of things you can do to improve a seemingly "good" stock air seal. Sealing up every potential leaky spot, gaining a few fps after each mod, eventually you're up to 455 fps on a spring meant for 390 fps. Like I said, when my M14 was stock, Modify S100 would give 330 fps, Modify S110 and MadBull M110 would give 360, the MadBull M120 I'm using now would give me 390, and the stock CA M130 gave me 425. Yes I actually did go through all of those springs in my gun. A lot of tuning later, 455fps with the same spring that gave me 390 fps.

I feel that spring test reflects more on the seal you can get from modify components as opposed inflated spring strength. For example, when I go back and forth between KA and Modify aluminum piston heads, I get an extra 35-40 fps on the Modify, even though the KA seems to seal quite well and give consistent fps.

You use aluminum piston heads?

A lot of the time, yup. Are you saying I'm not supposed to =P

Why would you want to have more mass on a moving assembly?

I just like that they're pretty much indestructible. I've never had any issues with my piston assembly being "too heavy".

Just saw those NanoAB3/4 in your sig, I'll probably pick one up when your battery restock happens.

Do you have them CNCd ?

Do you mean if I have them machined out of a solid block and not cast?

Frankly I don't see why they would break. If they did, they are cheap enough to just replace.

Thanks for the answer. Just hoping you might have the CNC ones. I have PDI in my several of my M4s and a G36 and not a single failure in 4 years. Whereas I had a few of the pot metals go already. So for $20, CNC ones are not expensive.

http://www.airsoftgi.com/product_inf...oducts_id=5622

http://www.airsoftgi.com/product_inf...oducts_id=5623

Engineer hat on...

How do they break? Do they snap in half somehow?

Cut off levers usually wear down before they snap.

Laterally they shouldn't move, so the only way it can snap would be longitudinally. This can only happen if you're in semi, the sector gear cam pushes it down, but the lever side is somehow stuck underneath the trigger sled. It's a really rare instance where something has jammed things up. You probably have bigger problems to worry about at that point though.

John

Maybe they wear out. I find pot metal tends to crack first, besides the CNC ones do last longer.

Also the pot metal lever in my VFC also wear out very fast and no longer hold the hop up cover open. Replaced those a few times as well.