we m14 HPA tapped mag?

[jarrichamp]

Hi all.

i was wondering if there was any one on here that could help me with tapping a we M14 gas mag for use with HPA rig? has any of you done this in the past? and if so, what are your experience on this??

[PureSilver]

Re: we m14 HPA tapped mag??

To cut a long story short, it can be done, but you need to be very careful in setting it up; set the regulator pressure too high and the magazine will essentially become a bomb. I've not done an M14 but the procedure is much the same as for any other magazine. Apologies in advance if I tell you loads of stuff you already know, but better safe than sorry.

The long story:

1. Create your HPA rig. You will need a specific low-power rig - a dual-regulator one intended for Polar* use (e.g. a RedLine) would be ideal; Palmers may also do HPA-capable ones but be aware that most of their airsoft stuff is geared towards CO₂ (c.800psi) and therefore not safe to use with HPA (3-4,000psi). You can either buy a completed rig or assemble it yourself; again, I'm sure you already know how dangerous HPA is if not treated with extreme caution so be extremely cautious!
2. Tap the magazine. The simplest and safest way to tap the WE M14 magazine (in absence of a CO₂ version you could use an adaptor on, like a KJW M700 or similar) is to unscrew the original fill valve, and tap that hole for a quick-disconnect fitting to suit your rig. To do so, you'll need a 1/8" drill bit, a 1/8" NPT tap, and a vise to hold everything steady.
3. Start by disassembling the magazine as completely as you can. Small bits of swarf and the like will fall into it during drilling and tapping, and you don't want those going through the valves or the rest of the gun when it's fired.
4. Drill out the fill valve hole with the 1/8" drill bit, and deburr the hole.
5. Tap the hole carefully, slowly and completely with the 1/8" NPT tap. In an ideal world you should use tapping, drilling or cutting fluid, but if you do it slowly, back off a half-turn every full turn, and use oil instead you should be fine.
6. Deburr and degrease the threaded hole; you may wish to wash the magazine in warm soapy water to remove any remaining fluid or oil.
7. Screw in your 1/8" NPT QD fitting. If you want it to be removable, use teflon tape. If you want to be sure it will never leak, use a generous helping of metal-to-metal epoxy glue, being careful to wipe away any excess. You will need to get the glue right the first time; if it leaks after that it will be hard to fix.
8. Reassemble the magazine, and set the regulators LOW. You will want to experiment to find the ideal pressure but be careful to never exceed the equivalent pressure of propane at a reasonable temperature (e.g. a maximum of 40°C). If you need more power, fit high-flow magazine valves rather than upping the pressure in the magazine - remember, it was not designed to hold 3,000psi!

[sparrowhawk]

Re: we m14 HPA tapped mag??

is it possible to add a release valve which can prevent it from building up too much pressure?

[PureSilver]

Re: we m14 HPA tapped mag??

Yeah, I should think it is, but you shouldn't need one and the more holes you put in the magazine, the weaker (and harder to seal) it gets. One way to keep safe would be to set the primary regulator carefully and don't disturb it - anywhere from 80-120psi should be OK, I should think - and only use the secondary regulator for fine adjustments. Although people do blow their magazines up occasionally (usually in brutally overpowered Tanaka builds) in general something else will break first if you ramp the power up in a linear fashion, which keeps you safe. The critical thing to do is not leave the regulator stuck on some insane psi level the first time you connect the rig to a magazine.

[StargateP90]

Re: we m14 HPA tapped mag??

That should be a sticky. What an exellent reply.

Sent from my GT-I9300 using Tapatalk 2

[Heinz]

Re: we m14 HPA tapped mag??

I've converted numerous GBBR mags to run from HPA. I'll add a few things to what PureSilver has said, If I may

Don't bother with Palmer's kit. Way back in the mists of time they were acceptable ('cos they were the only people who did regulators with a low enough output for classic external tank Airsoft guns), however, rigs like the Firebase crap all over all the Palmers gear these days (also, the Redline has a decent enough regulator that you don't need to bother with a seconday reg, like the SMC AR-10's you used to almost have to use with the Palmer's kit as their regulators had very course adjustment). Also, the Redline has a pressure valve built into it that blows at 140PSI, and finally, the awesome flexible braided line thats about a thousand times better than the evil that is Macroline.

[PureSilver]

Re: we m14 HPA tapped mag??

Don't bother with Palmer's kit. Way back in the mists of time they were acceptable ('cos they were the only people who did regulators with a low enough output for classic external tank Airsoft guns), however, rigs like the Firebase crap all over all the Palmers gear these days

I've never heard it characterised that way before, and that's really interesting, thanks. I'll put a Firebase on my Christmas list, I think, and start looking into left-handed bolt actions. Off-topic, but is the old APS2 any good (since that's the only one that's easy to convert)?