[B&T MP5 issue with feeding]

Yes I was just going to recommend them clips. Very useful on a V2 box as the trigger likes to pop out aswell.

 

Yea as said above, just take your time on the gearbox. There is no rush. You will only end up having to strip the entire gun again if a problem arises. Been there so many times 

 

Just double check with the new sector gear and delay chip that the tappet plate pulls back far enough to load a BB and far enough forward to seal against the bucking.

I find MP5 to have small tolerances when it comes to this. If your running a full stroke then timing will not be an issue. 

 

There are guides online that walk you through this. Might be related to Short stroking but still relevant information

[What gearbox shells are decent these days ?]

If your running an MP5 I'd get the Systema Revoultion gearbox casing. Absolute tanks 

I've currently got one in a TM mp5 from like 20 years ago running at 34rps ssg. 

[Cyma M14 - needs a bit of fettling]

The prommy 6.03 barrel is a good clean barrell. I've got one in my TM M14 long version. The barrell is 500mm so end up abit pricey. Good quality barrel inside and out. Just needed a clean. The only thing I find about them is the window is abit narrow. Not alot of contact patch.

The maple.leaf Mr Hop never fitted this barrel. 

Ive had to file out the windows to open them up and allow more contact a few times

 

Best results using a 500mm prommy barrel I find are: Full length cylinder, Flat hop using omega or H nub and prommy purple bucking.

Maple leaf bucking but with a little window work 

Or Rhop - IRhop. 

I personally run an IRhop.

 

420 fps .4s are gone

 

ZCI make one and I'm sure it's a 6.02. You can get these in any length and they have the m14.cut on the barrell. Which means you can short stroke the 18:1 by a tooth or 2.

Ive SS my M14 AR by 1 tooth and run a 363mm 6.02 for a snappier trigger and over volume for those heavier weights

The window is wider on these so you can use maple leaf MR hop etc in them. I have had a couple that haven't fitted as nice and again filled down the window to open the gap up atad 

Or just Rhop this barrel

Elvish tac make a drop in patch for the prommy one and maybe the zci. To be honest they are small I think. I make mine instead for myself and customers. 

 

AOLS also make a 6.02 or maybe 6.01 cant remember now. The clean closet to the ZCI in quality and over appearance. probably out of the same factory.

 

 

If you are looking to do internal work then thats a whole other story 

Alot of pitfuls and sourcing parts.

Tbh the internals for the CYMA variants aren't great. Most.of it comes out when I build one of them.

Only real part that's left is the tappet plate as they are specific to Cyma. Shs tappets do not feed in a cyma. Or not many. 

 

I generally just work on V7 m14s for myself and customers. So any questions let me know mate.