Upgrading the spring on a CA M15A4. What's required?

[Crunchmeister]

I want to upgrade my stock CA M15A4 rifle with a Prometheus Non-Liner MS110SP so I can get a bit more power out of it.

Now, I know with a Marui, you need to also replace the nylon bushings, and it's recommended to also upgrade the stock gears, since these parts have a hard time handling the compression of the heavier spring. I blew a spur gear in my TM M4 and ordered the spring along with new gears / bushing, etc to handle the upgraded spring.

If I want to also install the same Prometheus MS110SP spring in my CA, is there anything else that I HAVE to upgrade to handle this stronger spring, or would the spring on its own be ok? Do I need to upgrade gears or other components as well?

Also, I see these cylinders listed as half-teeth and full-teeth. What exactly is the difference between these two and what are their different effects on the gun?

[Ibby]

You should get metal bushings. That will be pretty much all you need to replace internally along with the spring. A new gear set is a good idea but not necessary right away. I would order a spare set sometime, just to be on the safe side.
The half teeth/full teeth thing applies to the piston. Some torque up gear sets require some of the gears to have a different diameter to get the added torque. In some cases larger gears won't fit without making space somewhere, and one place is to shave a bit of material off the piston. Unless you're getting a bigger set of gears, stick with full teeth pistons.
I'm back in Kingston the first week of Jan. If you like I can help you out upgrading your gun then. I have a chrony so the gun can be tested as well.

[Crunchmeister]

Well, that would be cool. I'd love to get a good reading on my velocities. I should have my M4 all done up by then, but it doesn't hurt to have an experienced set of eyes looking on to guide me through the rifle's upgrade.

There'll be beer (or whatever your poison of choice is) in it for you.

[Flatlander]

I would recommend a tightbore barrel also. If you can afford it go with a higher end one (like Prometheus) but if you're cheap (like me!) go with a Madbull. Mine was like $35 from Jugglez (airsoftparts.ca) and it upped the FPS slightly and my groupingss were much tighter (m4 length). My first Madbull barrel was a dud (tephlon coating shredding immediately inside) but I received a new one right away for free with no troubles now and probably 5K + rounds through it. Great bang for buck, IMO.

[Crunchmeister]

Tightbore barrels are also on my 'to buy' list for both my AEGs. I'm not too concerned about the velocity, since the upgraded springs and whatever other internals I'll be getting will be taking both over the 350 FPS mark. To me, that's more than enough.

For the time being, I'll stick with the stock barrels. Both my guns shoot pretty accurately as-is. With the new upgrades coming for my M4, it will put it ahead of my M15 in terms of performance. I'd like to up the M15 first so it can outperform the M4 since it's a full-length rifle. But new inner barrels will eventually find their way into my gun. That you can be sure of.

[kalnaren]

To upgrade a CA spring all you *need* is a new spring guide. The bushings are already metal. Check the wear on the piston as well. I heard some CA pistons blow. In the case of my G36, the piston and bushings showed no wear or anything, so I just dropped in a Guarder bearing spring guide and an MS100SP

[ThunderCactus]

Your going to NEED a hopup rubber lol
It probably makes the biggest difference with your grouping, as I've seen 6.03 tightbores getting worse accuracy than a 6.08 barrel with a good hopup rubber. I recommend either the Guarder clear or prometheus soft rubber