[dobey]

I was watching Tears of the Sun a few weeks ago and have been wanting to really build a Suppressed M4 sniper for Airsoft ever since!

Reference:

I have this little anti-rotation link that replaces the body pin that aligns the gearbox in the body:

It requires another body pin in the gun to keep it secure, so I made these larger fake pins for that (near the mag catch):

Installed:

Cut the outer barrel in front of the gas block, I will be using a relatively long Airsoft Silencer for this and I don't want it 5 feet long:

Here I am cutting it down to size to thread it for 14X1.0mm CCW threads:

The new threads:

Upper Receiver coming together:

I will be shooting allot of chrono shots to set this up correctly so I made this to make things easier:

It will let me screw the chrono right on to the Airsoft gun:

Next I will get into this:

 

[oderfa]

It isn't fare that you can just machine all these things......... But at least you use your skills and machines to something usefull =P.

Looks good.

 

[dobey]

Thanks! I love making things, it really is my Zen.

 

[MGunner]

If you want a really quiet gun: Use the 550FPS nozzle with a low PSI, creating a high volume, low PSI sort of deal. I have a team mate that does this, he runs like 30 or 50 PSI below the recommended pressure, and it's super quiet and he still has awesome range.

 

[solarisjock]

How does that effect his gas consumption? I am starting to save up for a P* box to slap into my M16A4 for a DMR, and would like to make it a whisper killer as well.

 

[MGunner]

How does that effect his gas consumption? I am starting to save up for a P* box to slap into my M16A4 for a DMR, and would like to make it a whisper killer as well.

He fills up off a scuba tank in the morning and he carries about 10 midcaps and usually goes through most of them, pretty sure he uses a 48ci tank and he's never had to refill.

 

[dobey]

Thanks for the tip, I am already working on a custom high flow nozzle!

 

[woogie]

Very nice Dobey, and very nice machine work as well.


What kind of lathe are you running? I am still kicking myself for getting rid of my larger lathe.

 

[dobey]

It is a 10x15 3/4 from Bolton tools, been abusing it for a few years now and loving it!

Caught it on sale a few years ago for around $900 I think:

http://www.boltonhardware.com/categ...hines/metal-lathes/10x-15-3-4-bench-lathe.php

 

[woogie]

Very nice, but of course the lathe isn't the "expensive" part It is all that darn tooling and all the other goodies.

 

[dobey]

Sure is, the extras can kill you! I love machine work though, nothing more satisfying than making a part yourself.

 

[dobey]

I am running it on the compressor in the shop to save air in my tank, and so far first shots with the stock settings I am hitting 375 with 0.25's at 55 psi, using the same airline I will be using on the rig.

Custom nozzle seems to be doing its job!

 

[woogie]

NICE!!

Though don't see how that new nozzle will work though... how does the gas get from the back to the front

 

[fdkrew]

There is a tiny pin hole in the center, zoom in.







Just kidding

 

[dobey]

NICE!!
Though don't see how that new nozzle will work though... how does the gas get from the back to the front

I don't learn to drill holes until next week! :doh:

Here it is in the lower receiver, fits flawlessly:

I am cutting the inner barrel so it sticks out a bit from the end of the threads on the outer barrel. It will become apparent why later. First rough cut it on the band-saw:

After cleaning it up on the lathe and re-crowning it (60 degrees) I use a reamer to clean any lip the metal might have off:

And here it is all done:

Length:

I have a manufactured Mock Airsoft Silencer that I am using for this project, I have machined out part of the end cap like this:

This piece then screws on, locking that cap tightly in place. It will also be used to lock the inner barrel in place later with a collet.

Rest of it together:

 

[bitchtits]

Looking great already. Cant wait to see what you do with the p*.Its my next on the list of things to buy. Think I may have to run full auto here(350fps) as sites are picky about what can be used as semi auto dmr's. Some let 420fps if its locked semi others only if its designed semi( g&g sr25,RS Svd ect).
stupid I know as the box inside is still designed for auto.

 

[Bushmaster Recon]

looking nice man. looking forward to seeing it all together.

 

[Wolfgeorge]

That's awesome... Looking forward to see it finished.


Wolf

 

[zero]

Can't wait to see the final build, wish I had machining skills like you do!

Zero

 

[dobey]

The full auto switch inside the polar star gearbox shell was not activating perfectly, this is not a design flaw, simply a tolerance issue between the polar star and the JP bodies selector cam. It was just not pushing it back far enough, by a few thousandths of an inch, so I made a slightly larger (by 0.015 inches) engagement pin:

This is where I am at as of right now, lots to do but it is shooting decently so I will give it a try at tomorrows game:

I have full auto set to three round burst.