Two piece to One peice hopup mod?

[Rabbit]

Just recently bought another AEG and after a bit of reading and reviews found that it comes with a two piece hop up.

I've never actually gamed with a two piece and was just wondering if there were any pros/cons.

I understand a good amount of TM makes use the two piece design.

Would it be worth it to mod it so it takes a one piece? Again i've looked into it and most people end up ruining their AEGs due to feeding problems once this is done.

Perhaps an aftermarket two piece would be in my best interest?

[coach]

The mod is fairly straight forward but is not reversible. It's a matter of removing enough material so that a one piece will drop down and clear into the lower receiver. With a two piece, half is fixed to the lower and the other is attached to the upper. In normal situations, there's no problems with a two piece as they will mate just fine. The air seal is not affected. I only changed mine because the upper half broke when playing in extreme cold weather.

IMO, the feeding issues would be attributed to Mag/hopup unit compatibility. From what I recall, it is possible to also mess up if the lower isn't modded right so that the hopup doesn't sit square. Eg. More material is cut from one side and less on the other pushing it off center.

[m102404]

1. Are you having issues with the current setup? If not...don't mess with it.

2. What make/model?

3. Pros/cons...a one-piece should theoretically have a better airseal than a two-piece. However, a crappily installed 1piece is worse than functioning 2piece. Lots and lots and lots of TM's work just fine with a two piece hopup.

4. Not worth modding just for the hell of it...the material that you take out from the receiver structurally weakens it if the receiver isn't meant to be without that material

5. The only "aftermarket" two piece that I know of is either a stock KWA replacement, which goes along with a KWA nozzle...and a Guarder upper half hopup, which are so-so at best. Other than that, stock TM replacements are all I've seen.

[Reckless]

if theres no problems.. leave it alone.

most of the times I've ever seen or heard people doing the mod or swapping out are

1. they broke something... and honestly if it's a TM find another TM peice and leave it .. they work great

2. they are convinced by the internet that plastic stucks... or they think because it's 2 peices it'll leak.. so long as the nozzle seats , and the spring on the upper half is good enough to keep it in place .. they are fine..

honestly you'll get WAY more benefit with a good rubber, and making sure the hop nub engages enough to run a heavier BB .. the hop units are made to fit the gun/receiver.. if they are slightly out of spec (IE SRC...) then your gonna have way more headaches that you might not beable to reverse

the other part.. if your GOING to go ahead and do the swap... get the matching nozzle to go with it

[Jackarutu]

In the USA Echo1 still carries the two piece hops ups as used in the Echo1 VN M16. Thus in the USA any Echo1 dealer should be able to supply them.

I don't mean to high jack your thread but this is somewhat related:

A few years ago it came to my attention that the M16A1/VN, XM-177E2, Car-15 use a different air nozzle from the M16A2, M4A1/RIS/SR-16. To my shame I have had the question in mind but never investigated to understand why?

To me it seems like they all use the same receiver sets with the same dimensions and they all use the same barrels. The only difference is the hop ups. In the early days the M16A1/VN, XM-177E2, Car-15 all used two piece hop ups.

The only thing I can think of is those two piece hop ups came with a bucking the was flat on the end instead of the cone shaped bucking we are all familiar with these days thus the nozzle would need to be longer to mate with the flat bucking.

If any of my peers has an understanding of this I would appreciate them sharing their knowledge.

I also wonder if the new generation of M16A1/VN, XM-177E2, Car-15 being produced today use the one piece hop up or have they continued using the two piece?

Cheers

[Rabbit]

The model i'll be working with is the SRC M933 the Canadian version which doesn't seem to be the Gen I, II, or III.

I was reading over one of Illusion's old posts about 2 pieces showing more signs of leaks and Reckless - Yes im one of those suckers that seems to think Metal seals better than plastic - but ofcourse only through owning and working with different AEG's.

The AEG I just purchased was sold in perfect working order, I guess i wont mess around with it unless needed.

This post makes for an interesting read and learning expirience! Thanks all for the responses.

[Reckless]

if I remember correctly .. the tinted cnd src's are kinda right inbetween Gen1 and 2 ...

and they are slightly off spec.. the pistons are slightly shorter(as is the overall gearbox) , the piston seems to sit a touch higher up and the sector has taller teeth.. (the differences are minimal .. but they add up ) .. it also appears that the cyl head tube is slightly bigger, and thus standard spec nozzles don't fit.

on that note, the above is only important if you need to repair... except the nozzle bit... the stocker SRC nozzle is slightly (and like the rest of the above I do mean SLIGHTLY .. just enough to piss you off and not completely seal) too short for standard spec 1peice "drop in" hop ups...

so from my experience (4 across my bench) to do a 1 peice you need the hopup, mod the receiver, and change the cyl head and nozzle ...

now... those above guns were all owned by the same person... and the same person had previously worked on them... it is possible all of them had aftermarket "bore up" cyl heads installed

your mileage/experience may vary

if you are dead set on a metal hop up ... I have atleast 1 metal hop that has had the bottom cut off to fit the 2 peice SRC style .. (taken from one of the above mentioned src's) .. doesn't have any inards in it .. I'm sure we could work out something cheap (like.. shipping) if your so inclined to have one.

personally .. I'd say if swapping the hop for accuracy .. etc is firmly in your mind.. go all the way.. get the modify accuracy hop (or prommy.. etc) .. get the prom nozzle, get the Mask Duo cyl/piston head set .. and be sure it all works

[Rabbit]

Wow what? Blow my mind.

SRC mechbox's are "slightly" different from the standard V2s?

So due to the sector gear having a slightly larger teeth, a different brand gearset may not mesh well with the rest of the guts.

Im assuming I now just wouldn't be able to throw a dropin V2 mechbox in there and expect it to work right off the bat.

Gathering what I read from your post - lets just say I was upgrading for longevity - new cylinder head, nozzle and what about the piston? Seeing as how it is shorter would a standard length one suffice?

[Amos]

In all honesty -- an SRC isn't something you should look into upgrading, it'll just turn into a nightmare.

[Reckless]

Originally Posted by Remylebeau

Wow what? Blow my mind.

SRC mechbox's are "slightly" different from the standard V2s?

So due to the sector gear having a slightly larger teeth, a different brand gearset may not mesh well with the rest of the guts.

Im assuming I now just wouldn't be able to throw a dropin V2 mechbox in there and expect it to work right off the bat.

Gathering what I read from your post - lets just say I was upgrading for longevity - new cylinder head, nozzle and what about the piston? Seeing as how it is shorter would a standard length one suffice?

as for longetivity ... shim it, check the engagement of the piston to the gears, etc .. and run it till it explodes... (2 of the 4 across my bench had litterally 100,000+ rnds through em, owner loves box mags, and the trigger)

as for just dropping in another complete "better' gearbox... yes it works just fine

[Rabbit]

So i received the SRC.

Not firing right off the bat - From what i've narrowed it down to, the motor is not strong enough to pull the stock spring it has inside.

I grabbed my trusty JG High torque to give it a shot - the pinion gear size is different! So i can't even try it out to see if it works.

Because it was the stock spring I didn't really give a shit about - I nipped a couple rings off it then stretched it out to see if that would help, still nothing - not firing.

Mind you the gears turn just fine, nothing is jamming or ceasing - even when I have the motor outside of the mechbox and a battery hooked up, pulling the trigger still gets the motor to spin and operate - its just when I slip it inside.

Damn you SRC and your bargain prices!