Echo 1 M4 to SPR Kit

Okay, I own an Echo 1 M4 TC (Full Stock M4). I wanted to make into a DMR because its accuracy sucks. So I was planning on buying a tightbore barrel and suppressor, when I found this sweet SPR conversion kit:
http://www.airsoftpost.com/product_info.php?cPath=25_86_267&products_id=28683
Since it's a Matrix kit, I assume that it will fit on the Echo 1 M4, but I didn't want to spend $100 and have it not work. Thanks.

It will not include the inner TBB your looking for. So it will actually run you $50 high.

I would compromise on a shorter 6.03 TBB around 400 mm. (The best TBB I have used are the Prometheus stainless series which are more accurate than my brass TBB's...but I also polished it which has given me very tight spreads I am proud for.

For the hop up. A lot of people just like to install the neo when they do not need it. I would actually try investing in a angled bucking http://www.airsoftatlanta.com/product_p/44152.htm Which are designed to evenly distribute the air around the bb as it is leaving the chamber for a more uniform flow giving you pretty good accuracy in return. I am not sure which angling would suit you, but I'd imagine 60-65 degree would be fine.

IF You plan to do a real M16 conversion, you should get a non-ported cylinder.

And lastly purchase heavier bb's They will not cost much more than regular .2's but the weight will give your bb's more inertia and accuracy. I recommend .25's

This should all be closer to your budget.