PTW M16A1 build

[Opossum]

I decided I needed a new project!

I found a Prime M16A1 lower, which I wasn't aware they made, for a cheap price. It was advertised as an M4 lower but I snapped it up after realising what it was.

I hadn't planned to use it for anything, but after a lot of "umm"-ing and "ahh"-ing I decided to make something using it. I took apart my donor gun:



(Which was far too heavy) and went about beginning a retro build. I have all the front end and stock parts to make an XM177E2, but it would defeat the object if I'd got an M16A1 marked lower, so I decided to go the whole hog and make the M16

The major stumbling blocks are:

• The usual full stock for the PTW, which I have, is an M16A2 one. This is a bit too long and has the wrong buttplate - also I don't have the correct wiring for it. It uses a different set of wires than the sliding stock models.
• The outer barrel on an M16A1 is the thinner "pencil" style compared to the thicker M16A2 one, and the A2 barrel I have spare won't fit into the lathe

The first solution is to get an original M16A1 stock. Fortunately these have the trapdoor in them and plenty of space for a lipo. The problem here is that I need a real rifle length buffer tube to fit the stock onto. The plan is to cut a hole in the tube to pass the wires through into the trapdoor space in the stock.

As I couldn't lathe the A2 barrel, I had to find an alternative. Fortunately FCC do a steel multi-part barrel (I know they do aluminium ones but it will be far too light). I usually don't like the idea of these as I like something for the front sight to butt up against. What I can do is take the end section of the barrel, which will fit in the lathe, then cut down the amount I need. This will leave me with the right barrel thickness and a portion for the sight to butt against. I will then threadlock it all together and cut the front sight pin notches. The total barrel profile won't be correct for an A1 but that will be hidden inside the handguards.

I have most of the lower parts, but am waiting for a HK order to come through with the upper parts:

On their way:

• Real rifle length receiver extension
• FCC A1 upper
• G&P M16A1 front end kit - This was for the handguards, handguard cap and flash hider
• FCC steel multi-part barrel
• Systema magazine release (The donor one is an ambi one)
• Etiny burst CPU

Today I received some original Vietnam M16A1 handguards and stock. The right-side handguard is a bit melted, but is structurally sound. The stock is awesome and a much more manageable length than the A2 ones as it's an inch or so shorter. It'll need a bit of modification to let the wires go through into the cubby hole but it shouldn't be too difficult.





Melted...?

I plan to update this thread when I make progress. The HK order will take a couple of weeks, but the lower should be finished soon. Let me know any thoughts, criticisms or advice!

[Fitch]

Re: PTW M16A1 build

Interested in following this

[Opossum]

Re: PTW M16A1 build

The stock tube turned up today! A few strategically placed holes were added and the wires threaded through. It works better than expected! I was woried that the wires would be difficult to reach.

The cutout for the wires:



The wired feed into the stock:



The finished lower:



I'm awaiting a new burst CPU, which unfortunately I bought on a whim when someone mentioned that the A1 has burst... Research suggests the A1 is full auto. Fortunately the CPU is changeable between burst and auto so I can use burst (Because it's awesome) when gaming and change it to auto when the stitch-counters appear :D I'm super excited that the difficult part is done.

The only downside so far is that the trapdoor needs a screwdriver to open as it's a bit stubborn.

Also, I'll try to get hold of a better camera than the one on my iPhone when it's done.

[madwelshman]

Re: PTW M16A1 build

nice, makes a change from all the L119a1 and 416 builds.... loving it mate, keep them pics coming!

[dave38x]

Re: PTW M16A1 build

Glorious! Simple is best sometimes!!!

[mightyjebus]

Re: PTW M16A1 build

nice so far.

couple of questions:

is there a spacer missing from the stock/reciever? the gap where the stock ends and the receiver starts seems to have a gap.

If you are getting a pencil barrel then will a normal PTW front sight fit?

I built a XM177 PTW so I know how good it feels when the parts start to go together/

[Opossum]

Re: PTW M16A1 build

Love the XM177!

The "Gap" is just the very shiny receiver extension. The standard Systema front sight won't go on as the pencil barrel will be much thinner.

I already built a PTW 733 but is missing the forward assist and flash hider. Don't fancy trading uppers do you? :D I do love my slick-side upper though!

You can see the correct pencil barrel on the 733 below, which will be the thickness I'm aiming for on the A1:

[mightyjebus]

Re: PTW M16A1 build

I take it that the G&P A1 front sight will fit?

That slab sided receiver could be used on the M16 to make it an early issue version or dare I say it a CAR 15

[Opossum]

Re: PTW M16A1 build

Yeah my 733 uses a G&P steel A1 front sight, minus the bayonet lug. For the A1 build The FCC multi-part barrel will be put on the lathe so the G&P front sight fits on nicely.

But seriously, if you ever want to trade that 733 upper let me know. I have the FCC A1 upper on its way which would be spot on for the XM177 as it lacks the brass deflector. The slick side would go on the A1 and we'd all be happy

[mightyjebus]

Re: PTW M16A1 build

sounds like a plan. I'll drop you a PM.

[Opossum]

Re: PTW M16A1 build

Well with many thanks to Mightyjebus I was able to put the correct upper on the 733:



And was able to mock up the A1 with the slick-side upper and A2 barrel:



If I keep the slick side upper it'll technically be an A1 with a Model 604 upper.

Also, I had enough spare parts to begin building an AEG Model 604 for my brother to use. That means the remainder of the G&P front set I bought for this build won't be wasted. It'll have the "AR-15 Model 02" marked slab-side lower, with the slick-side upper and duck bill flash hider.

I'm still awaiting the HK order with the A1 upper(s) and the outer barrel bits

I've also bought a few bits and bobs to make a crude Vietnam loadout.

[steve grey]

Re: PTW M16A1 build

Great work Opossum, keep us posted mate...

[happyal]

Re: PTW M16A1 build

Cool project, any updates?

[Opossum]

Re: PTW M16A1 build

Cheers. The upper parts have finally been posted... but I used the bodged together version seen above yesterday and was really impressed by it. It's very solid and quite heavy!

[Abbadon101]

Re: PTW M16A1 build

Did you get the A1 upper for FCC? I am wanting to make a 773 upper but finding the proper A1 upper is proving troublesome.