New HopUp. Barrel Upgrade?

Like many other airsoft related things, I know Jack "Watch your language" about the actual hopup it self. I have a 100% stock G&G combat machine m4 (non blowback) so teach me (links would be nice) what should be replaced with what, for max performance. Also should I replace the barrel? Ive heard that the non blowback CMs don't have the 6.04 mm barrel, so do they? If not, link me a good barrel to get.
Was thinking this for hopuphttp://www.airsoftgi.com/product_info.php?products_id=5986

Bumpin

@Wertuk,

You need to know what you plan to achieve with your Combat Machine M4 Replica. For example, ask yourself the following questions: Is it okay as it is untweaked? What is my average range of engagement? Do I use my RoF to pin opponents, or my gun's accuracy to make them think twice about going around that tree?

My average range of engagement is easily 50 plus feet, but I don\'t seem to be hitting anything passed 75 with much accuracy. The nice RoF helps, as much of the time I can spray a 10-20 round burst and an exposed person, but just because of the wall of bbs. I come into situations where I have a target dwonrange, and just the head is exposed, and I would like to hit them instead of hitting everything around them and making them put there head down.

Wertuk wrote:

My average range of engagement is easily 50 plus feet, but I don't seem to be hitting anything passed 75 with much accuracy. The nice RoF helps, as much of the time I can spray a 10-20 round burst and an exposed person, but just because of the wall of bbs. I come into situations where I have a target dwonrange, and just the head is exposed, and I would like to hit them instead of hitting everything around them and making them put there head down.

Try a heavier bb. Use a higher gram bb, such as a .25. My E1 M8A3 does the exact same thing with the .20's and I don't have a TBB in it yet. TBB will hone the spread of your bb's yes, but not as well as simply finding the right weight and hop up calibration. Try the bbs first if you are not sure about doing the upgrades.

I was using G&G .25 bios =/ I they all more or less were in a vertical line, but it felt like the hop sometimes dint do anything to a bb

Wertuk wrote:

I was using G&G .25 bios =/ I they all more or less were in a vertical line, but it felt like the hop sometimes dint do anything to a bb

Well it might have been the shape of the bio's as well. It's rare, but sometimes they may start decomposing slightly while in their bag if it's already been opened. And the rate of decomposition is just enough to throw it off.

So try it with regular nylon bb's before ruling out hop up and barrel upgrades.

Nah, G&G bios don't do that. If I have my facts straight, all G&Gs come with a 6.03 barrel. That hopup would keep your options open if you wanted to do an easy drop-in HUTU later on. In addition, I'd recommend a new hopup nub.

I've upgraded to a 6.01 barrel, Systema hop chamber, and prommy soft bucking in my G&G GR-16, but am still falling short. I also use G&G .25g bios. Something the (very knowledgable) guys on Airsoft Pacific recommend is an H-nub or similar. Some of them say specifically an SCS nub is what you need for range and accuracy. I've got one on the way right now. They're expensive for what they are, but certainly cheap for what they do.