Fitting PTW stock tube

[Mike581]

Ok I whipped the stock tube off my PTW to remove the sling adaptor and now when coming to refit I realise I didn't take note of how far in it was screwed.
Any tips on how to set it up correctly as I know if it's wrong it can affect fps / wear / chopping etc
Cheers

[r6shooter]

Re: Fitting PTW stock tube

Hey mate

He stock needs to go in far enough so there is only enough room left on the inside o the reciever for the tub cap and spacers,

So screw it in all the way fit the cap and two spacers and undo until you can close the upper reciever and it's a nice firm seating click

I have two thin spacers on mine and from the stock tube nut I have 7 thread but I have a four mm thick sling point

[Identiti]

Re: Fitting PTW stock tube

Just sore this post after you pm'ed me, this is how mine is set

[Mike581]

Re: Fitting PTW stock tube

Yeah I have a magpul ASAP plate fitted and I'm showing 7 threads at the rear.
In the pic mate mine seems a tiny but further back but I have a small metal spacer on my plug. Have you got any spacers on yours?
With the plug fitted in it now sits the tiniest amount proud of the upper receiver, if you know what I mean

[Identiti]

Re: Fitting PTW stock tube

Yeah i do have that plug, just took it off so you could see where the stock tube ended.

Sounds like u have it on there right though.

If the stock tubes not in far enough the upper will just push back together to easy, so how u have it now, u shud need to give it a little bit of effort to get it back down if that makes sense

[r6shooter]

Re: Fitting PTW stock tube

nooooooo

please make sure you have it flush not proud or recessed with the reciever

the blanking cap is basically filling the reciever void, so it has to be level...
it also acts as the backing for the cylinder ad it keeps it perfectly lined up due to the movement and torque of the gearbox.

having it recessed will cause strain and damage on the cylinder components as they are able to move around a little too much ,
having it proud will make it stress the gearbox making it over heat due to being too light

[Identiti]

Re: Fitting PTW stock tube

This is how its fitted from Tac dude and so are my mates ptw's

The cap has spacers on it so that it can be fitted and adjusted depending on the brand and type of tube fitted due to slight variations

If i screw my stock tube up one more full turn it will stick to far inside the body which is where the spacers on the cap come into play

[r6shooter]

Re: Fitting PTW stock tube

This is how its fitted from Tac dude and so are my mates ptw's

The cap has spacers on it so that it can be fitted and adjusted depending on the brand and type of tube fitted due to slight variations

If i screw my stock tube up one more full turn it will stick to far inside the body which is where the spacers on the cap come into play

yeah i know

with the cap and spacers on and installed it all has to sit flush with the reciever so the cylinder performs the best it can without damaging mate

[Mike581]

Re: Fitting PTW stock tube

Right guys, with no spacers fitted best I can get is about 0.5mm below, with a spacer fitted it sits proud by 0.5mm.
What's my best option here?
In both positions the upper closes nicely with the right feel, not too easy, not too hard

[Mike581]

Re: Fitting PTW stock tube

Bit of an update...
Put a mag thrPugh it with spacer fitted and it chopped a couple of the bb's.
Put a mag through with no spacer - so plug sitting a tiny bit below - no chopping.
So I assume no spacer?!

[r6shooter]

Re: Fitting PTW stock tube

depends mate,

what type of pmags you using

the rambo ones need a tiny bit of the lip of the mag removed so it sits flush with the hop unit this will cause chopping

also the vanaras mags need shimming so the mag internals sit central and flush to prevent chopping

also the chopping isnt caused by the spacers mate,

i have three spacers in my m90 cylinder making it 360 fps and not chopped one bit,

check the mag spring and also check the hop unit as a piece of bb will block the loading and cause constant chopping

[Mike581]

Re: Fitting PTW stock tube

Using standard systema mags mate, whole gun has been stripped and put back together so hop is clear.
I know chopping can be down to individual mags, if springs are weak or they need a clean and lube but I used the same mag with and without spacer.
I just need to know really if I'm alright with this plug not being quite flush. I read the challenge kit instructions and it's not that specific when it comes to stock tube fitting

[r6shooter]

Re: Fitting PTW stock tube

yeah mate, the cap in the stock tube has to sit flush with ther reciever mate,

so when its in and pressed in firmly, just have a ruler across the reciever walls and and the plug to see if flat and level,

also the chopping mate, could be due to the mags ( are they new ones ) also what weight ammo you trying to shoot

the HW mags will take upto .3s the normal mags will only take upto .25s mate,

[Mike581]

Re: Fitting PTW stock tube

Just had mates new factory ptw open and his is about 0.5-1mm proud.
The mags aren't new they're used but in good condition, using excel 0.25