Spring Comparison Chart - Updated April 1st, 2006

[HerrMann]

I just had a Systema m100 spring put in my gun, get it home and plug in my 9.6 1700 mah bat (fully chargered), turns over once and then nothing? I this a case of my bat. not having enough mah to crank the spring?

[Amgoosen]

9.6v is more than enough to turn over a M100, perhaps something was put together improperly.

[The Saint]

Hey ILLusion, I was just looking at your spring test gun's spec today, trying to potentially imitate your setup. I noticed that you had the KM TN tapered cylinder. I was under the impression that you said they wereno good for guns over 1J. Is there a mistake on the specs of the test gun, or did you discover something new about the cylinder's performance for guns over 1J?

[ILLusion]

Originally Posted by Amgoosen

9.6v is more than enough to turn over a M100, perhaps something was put together improperly.

ditto.

I'd say to check your fuse to see if it popped. A tightly shimmed gearbox or unadjusted motor height could require too much current to cycle and in the process, popped the fuse.

Originally Posted by The Saint

Hey ILLusion, I was just looking at your spring test gun's spec today, trying to potentially imitate your setup. I noticed that you had the KM TN tapered cylinder. I was under the impression that you said they wereno good for guns over 1J. Is there a mistake on the specs of the test gun, or did you discover something new about the cylinder's performance for guns over 1J?

You're referring to the KM TN tapered cylinderhead, not the cylinder itself.

[pinoyboy]

question about the systema m130. I think I read somehwere that systema rates the fps of their springs with .25g BBs. I think you said that illusion. So that would be around 420-430fps with .25g correct?

[ILLusion]

From my experiences with springs, that would seem to be the case, although there are some situations that would make the resulting velocity to be different from what's calculated or what my chart says.

Some things that will affect variances in velocities:
- Inner barrel length
- Inner barrel bore
- What spring guide is used
- What piston head is used
- What BBs are used
- What gun platform are you using? AUG, P90, H&K, Armalite, etc? Some guns (like the P90) have a much better gearbox to feeding/hop up chamber to inner barrel connection and experience less air seal losses than other platforms. This is a big reason why most inquiries I get are why a user's velocities do not seem to be as high as in my chart.

[pinoyboy]

My gun is a G36. The setup is
509mm 6.01 tightbore
type 0 cylinder
bearing spring guide
vented piston head with bearing
air nozzle

[ILLusion]

Actually, I was just going over your initial statement...
M130 assuming meaning "130 m/s with 0.25g BB"

So 390m/s @0.25g is 1.76J
ArniesAirsoft FPS Calculator says 1.76J @ 0.20g is 437fps

I would say that number looks about right. In fact, I actually think that spring may shoot a bit higher in your setup. Perhaps up to 450fps.

[cjfield1129]

Originally Posted by ILLusion

You're referring to the KM TN tapered cylinderhead, not the cylinder itself.

I guess the same theory would apply to the taper design of the Prometheus heads and Systema bore up heads. Strange as I have always had better results with the taper design in my 400+ fps guns. Interesting.

[ILLusion]

Originally Posted by cjfield1129

I guess the same theory would apply to the taper design of the Prometheus heads and Systema bore up heads. Strange as I have always had better results with the taper design in my 400+ fps guns. Interesting.

Who said they were tapered? I have never seen any marketing material that stated they were. Even when I inspected them myself, I noticed no taper on them.

[cjfield1129]

My mistake, I was referring to the funnel shape on the piston striking side of the head. After additional reading, I realize that taper refers to the nozzle portion of the head. In that regard, is there a documented performance increase by using the type of head with a funnel as opposed to the flat surface such as the Area 1000 brand?

[ILLusion]

Quieter sound and reduced gearbox impact are the results of the funneled rear of cylinder heads. I don't believe there are any published documents with empirical results on this topic yet.

[brently0725]

A friend and I just installed PDI 120 springs in my TM MP5 SD5 and his G3 SAS and we were shooting 307fps steady. Just so you know for your chart if you want.

[BBS]

IMHO Illusion or someone should do a Sniper Spring Comparison Chart. a lot of threads have been started about Sniper springs and their fps output.

-BBS

[ILLusion]

Originally Posted by BBS

IMHO Illusion or someone should do a Sniper Spring Comparison Chart. a lot of threads have been started about Sniper springs and their fps output.

-BBS

It's in the works