JDT Steel Bolt Carrier Group Review

[sebin90]

No, they jams when they got opened, and releases all gas.

[mutikasha]

Did you use lot's of silicone oil on the valves prior to that?

Some grades of silicone can freeze because of the expansion of the gas and leed to jamming of the valve. Whilst using Predator Ultra this was a normal occurrence for me because of the lube inside the gas.

[sebin90]

No I didn't. It does not work. However I bought stronger valve springs to solve that problem, and i am going to borrow a paintball bottle to check them out

Edited October 31, 2009 by sebin90

[Luis21]

No I didn't. It does not work. However I bought stronger valve springs to solve that problem, and i am going to borrow a paintball bottle to check them out

 

Please let me know because I am highly considering switching to GHK mags because the WA magazine design with all the o-rings is too lleaky on high-pressure gasses and I don't trust it much on CO2.

 

Thanks,

 

-Luis

 

[sebin90]

On greengas there is no problem.

But on CO2 orings in valves makes too much friction.

 

Sebin

[Luis21]

On greengas there is no problem.

But on CO2 orings in valves makes too much friction.

 

Sebin

 

Yeah, but I still need GHKs. I have no other option unless Pro-win releases their "CO2" mags they advertised a decade ago.

 

-Luis

 

[sebin90]

Pro-Win will release co2 magazines? As I know they only tested "no leaking" with CO2 on their movies...

 

edit...

And with NPAS on high fps setting they need to be modified to make the recoil still hard:) but this is easy

Edited November 1, 2009 by sebin90

[Luis21]

Pro-Win will release co2 magazines? As I know they only tested "no leaking" with CO2 on their movies...

 

edit...

And with NPAS on high fps setting they need to be modified to make the recoil still hard:) but this is easy

 

Yeah, they were supposedly going to release CO2-compatible mags.

 

They're taking forever...

 

I'm working out some deals for GHKs....

 

Also, a paintball tank is filled with liquid CO2, right? And it doesn't have that much pressure as gassified CO2 until it expands outside the magazine, right?

 

-Luis

[snorkelman]

Also, a paintball tank is filled with liquid CO2, right? And it doesn't have that much pressure as gassified CO2 until it expands outside the magazine, right?

 

wrong

 

co2 will exert 850 PSI of pressure at 20 degrees C - lower the ambient temperature lower the pressure, higher the temp higher the pressure

 

the only way you'll get less pressure from CO2 is by preregulating it and filling the mag with your lower pressure vapour at which point you'll get as many shots as the volume of your storage container allows - regulate it down to 100 PSI and store the vapour at that pressure in an M4 sized mag you'll get say 2 or 3 shots, at 200 a couple more, 400 a couple more again.

 

Pump straight unregulated CO2 into the mag you'll get a whole lot more shots..

 

..at risk of blowing the mag up - GHK mags are certainly better than conventional WA style mags but they arent good enough to provide safe and reliable storage for unregulated CO2. The valve block is die cast, the threads holding the tubes onto the block arent designed for that sort of pressure, nor is the thread for the valve itself, even if it did hold out it would be a constant accident waiting to happen with no inidcation as to when it will finally fail.

 

GHK didnt go tot he expense of sticking a honking thick brass tube with a meaty thread in place of the thin walled fine threaded aluminium tube their green gas AK mags have just for the fun of it (and thats on a mag that takes the CO2 caplet in a oner, and restricts the output to a couple of hundred PSI before it hits the valve block)

 

To be honest its pointless exercise IMO - if I'm at home then I could just as easily tap a line from an external rig onto a mag and run the mag at 100 odd PSI from regulated CO2 with none of the risks. Whereas if I'm on a skirmish field then I'd have no business carrying full pressure CO2 filled mags of that sort around with me anyway. One thing to risk embedding bits of mags into my own body if Im daft enough to fill em to that pressure, another entirely to go wandering about amongst other people who havent consented to be potential shrapnel catchers.

 

[Luis21]

Won't this allow me to regulate CO2 straight from a bottle?

 

http://www.airsoftcarolina.com/index.php?p...8&parent=72

 

I have it on the way already. I know the risks but if I can't really regulate the CO2 then I might not go with the CO2 route anymore since it can get up to 100 F or 39 C where I play.

 

@Sebin: Have you noticed any dangers when filling your mags?

 

Pro-Win hurry up and release your mags!!!!!!

 

-Luis

[sebin90]

@Sebin: Have you noticed any dangers when filling your mags?

 

Not yet. I am going to make something like that:

 

 

This is going to replace one of 2 tubes in magazine. Still designing...

 

 

[Luis21]

Not yet. I am going to make something like that:

 

 

This is going to replace one of 2 tubes in magazine. Still designing...

 

That's a good idea. Dual CO2s would be awesome.

 

Do you have the same Madbull CO2 charger that I posted on page 3?

 

If so how is it?

 

-Luis

[sebin90]

Not dual but single Not enough space in there to hold 2 of them in my opinion.

 

Yes, I have the same adapter. It is great, but you have choice - or unregulated, liquid CO2 in the magazine, or regulated, but dry.

 

Sebin

Edited November 2, 2009 by sebin90

[Luis21]

Not dual but single Not enough space in there to hold 2 of them in my opinion.

 

Yes, I have the same adapter. It is great, but you have choice - or unregulated, liquid CO2 in the magazine, or regulated, but dry.

 

Sebin

 

I'm assuming that liquid, regulated CO2 is the safest and more fits inside the mag, correct?

 

-Luis

[sebin90]

Hmm liquid CO2 is most like greengas (gg is unregulated too), but at 6x higher pressure. So when it is liquid, there is a lot of it in the mag, but at high pressure.

 

You can't liquefy CO2 at for example 300psi (at low temp. for example -40 oC it is possibble). So regulated at lower pressure you can put only gas in magazine - for 2 or 3 shoots...

[Luis21]

Hmm liquid CO2 is most like greengas (gg is unregulated too), but at 6x higher pressure. So when it is liquid, there is a lot of it in the mag, but at high pressure.

 

You can't liquefy CO2 at for example 300psi (at low temp. for example -40 oC it is possibble). So regulated at lower pressure you can put only gas in magazine - for 2 or 3 shoots...

 

So I need to have it at a high PSI in order to fill up a whole magazine, 50 shots?

 

Also, what about gassified CO2? Is that more dangerous?

 

-Luis

[sebin90]

Yes, to reach 50 shoots you nid very high PSI.

 

Gassified CO2 has lower pressure, so it is safer

[mutikasha]

@Luis

 

That madbull adapter that you ordered is meant to be used with their 40 mm, grenades and such. The reason why it is good for that use is that you can put regulated CO2, at let's say 400 psi, and be assured it won't blew up in your hand - if used with correct 'nades. At 400 psi CO2 is in vapor state in normal temperature conditions and the amount of it (in gram equivalent) that you can put into that grenade is the same no matter if you use a CO2 88 g canister or a 12 g one which is standard for that adapter. It is because it is in vapor state. This is no biggie because grenades are one shot deal and they use all 400 psi in one go.

In contrast you have your GHK mag...

Putting regulated CO2 in your mag at 400 psi means that the first shot you fire will be at 400, second at 250, and the third won't even have enough strength to cycle. This is because the amount of CO2 that a GHK can take in vapor state is (I don't know how much propane it can take but let's just say it's 10 g) somewhere in 0,5 g equivalent. You can't put more hooking it up to a bottle, no way.

Putting unregulated liquid state CO2 in your mag is somewhat different. If you use 12g CO2 caplets, you can put lets' say 6 g of liquid CO2 in your tank...this is because of the small volume of the caplet and simple physics...when balance in pressure is established, CO2, won't flow to the mag anymore. When using a 88 g CO2 bottle, you can fill the whole 10 g into the mag - that's why Sebin got better results when he hooked up the mag to the bottle.

 

Only way CO2 can work at lower PSI from the 1g caplet is to hook it up direct to a mag with the internal regulator - like sebin has sketched.

 

Hate to break it to you, but CO2 adapter won't be of a much use to you unless you get some madbull grenades.

Now, since I written my *albatross* of, can you please look is the forward assist working with 5ku lightweight bolt carrier, pretty please. You don't need a nozzle for that.

[Luis21]

I just received my Madbull CO2 adapter(XC03). The online manual says that this adapter regulates and fills mags with CO2 in gas form.

 

I guess I'm pretty much screwed since I won't be able to fill up my whole mag...

 

Sebin, how exactly did you do it? Can you get one full magazine of BBs on one CO2 charge?

 

Thanks,

 

-Luis

[sebin90]

Don't use adjuster, and use only a "top" part with paintball bottle. That is how you can make it

[Luis21]

Don't use adjuster, and use only a "top" part with paintball bottle. That is how you can make it

 

And that'll give me about 800 PSI of liquid unregulated CO2, right?

 

-Luis

[sebin90]

And that'll give me about 800 PSI of liquid unregulated CO2, right?

 

-Luis

 

Yes

[weekenny]

Luis getting back on topic did you weigh the bolt carrier before and after machining? Any results yet?

 

Thanks

 

 

[t_hum]

Just put it back in the mail for him today. He should have it Thursday. It was terrible to machine. The steel used is gummy and ate a few end mills. So for the side cuts instead of milling slots I just marked hole locations using the mill and a center drill 5/8 of an inch apart. Those marks were then drilled using a 1/4" bit. I didn't have a scale to weight it on before I sent it back though so your guess is as good as mine.

 

 

As far as the whole CO2 thing, my personal opinion is that its a pretty dangrous idea. Yes, it has worked a few times, but will it continue to work without failure? I value my hands, eyes, and general well being too much to mess with liquid co2 in non hydrostatically tested containers. There is a reason bottles designed to hold high pressure and liquified gasses go through strict testing and inspection standards. Whatever performance boost you hope to squeeze out of your guns by using this method certainly can't be worth the risk.

My .02.

Edited November 10, 2009 by t_hum

[weekenny]

Looks like a decent amount of material was removed, that said its only around 0.007g per cu. mm so it'd take a fair chunk to get 80g. Approx 20 1/4" holes by my reckoning.