Echo 1 M4... disappointing

Okay, I recently upgraded my Echo 1 M4 with a new TBB. I am a little disappointed by the results listed below, but am I expecting too much from this upgrade? Also, these were done within 48 hours of each other, from a stable crouched position at 125 feet.

Test 1--Stock 363mm Barrel
Temp: 42*F
Wind: None
Accuracy (SA): 8-12 in (w/ 1 outlier per 5 rounds)
Accuracy (FA): 6-12 in (w/ 1 outlier per burst (on FA, 3-5 rounds a burst))

Test 2--JBU 509x6.03mm TBB
Temp: 38*F
Wind: Slightly across to the right
Accuracy (SA): 6-12 in (w/ 1 outlier per 6 rounds)
Accuracy (FA): 6-10 in (w/ 1 outlier per 3 bursts (on FA, 3 or 4 rounds at a time))

P.S. I can upload a pic of my backyard with circles representing the spreads, since these are all estimations.

If you are using .2g BBs, use .23g. It helps accuracy a surprising amount without sacrificing too much power.

EDIT: Also .23gs aren't affected by the wind as much as .2gs are.

Yeah try heavier BBs and maybe drop better Hop-up bucking in as well.

I've heard bad things about .23s though... But I'll have my friend come over tomorrow, he's got lots of .25s.

Lots of bad things? The only "bad" thing about .23g BBs is that they decrease the FPS SLIGHTLY.

It's .12s that you want to steer clear from.

Eh, it was quality of the BBs themselves, I think.

Everyone knows that! (Except my friend who f-ed up his MP5 by using .12s)