Mad Bull springs?
 

After having a bum Promethius spring in my gun (MS100SP shooting 240), I don't want another Promethius spring. I was thinking a Mad Bull M110. I'm aiming for the 360-380 range (I don't want the AEG to be over 400), but I've searched here on the forum and found that people have had the Mad Bull M110 shoot anywhere from 360 to 425 fps?? Anyone have any recent experience with these springs? It will be going in a more or less stock CA36E.

For 360-380 fps you have a SP110 Guarder

I wouldn't be so quick to blame the spring. Check your air seals.

My experience with at 110 mad bull spring is that it was quite heavy. I installed it on a stock CA SL8-2 and was suprized that the motor coulden't pull it.
Then I cut 3 rings off and it was still pumping at 370 fps range... @.@

It was the spring. When I swapped the stock one back in, the FPS went back up to 315.

I had a Madbull spring in my MP5SD, bearing spring guide, airseal nozzle, 330mm tightbore barrel and was shooting 390-400fps, with the occasional one going over. I *think* this was with hop up off, don't recall. I did notice they are stiffer compared to the Prometheus ones.

A good suggestion for you is to get a Modify 100 spring, it's relatively spongy, I installed one (w/bearing guide) into a stock TM AK, and was shooting in the 360-370fps range.

Someone should make a "MS105" spring. MS110 gets me over 400fps and MS100 at 370fps. :)

Well, my gun was chronied when it was stock and it was shooting 315 (+/- 5). I swaped springs and it went down to 240, swaped back and it went back up to 315 (+/- 5). I've checked all the air seals around the cylinder/cylinder head, and they're good. It could be leaking through the hop-up I suppose, but unless stock the gun was actually suppose to be shooting above 315, I don't think it's developed any more air leaks.

Get a Modify 100 from Jugglez, that'll put you right in around 360-370fps (with a bearing spring guide) and is an easy spring for the mechbox and motor to pull back. I find the Madbull ones to be rather stiff and reduced the rate of fire in the guns I've tried them in.