A&K Masada range issue

[AhhCool]

Got my 2nd hand Masda A&K about a month ago. did some test firing and worked fine.

However on my first game with the masada after 10-12 shots the range of the BB just dropped off massively. now the BB travels no more than 10ft!

The motor sounds like its going fine.

a couple of the marshals tried to diagnose the fault. 1 said the air pressure seems low after putting his finger in the muzzle break while another reckons i have a hop-up issue / firing with no hop?

I'm pretty much a n00b with internals. so i can't really determine whats going on?

[josh426]

Re: A&K Masada range issue

Most likely a stripped piston?

[HuntR]

Re: A&K Masada range issue

Most likely the hop arm has either crept forward thus reducing the hop effect. Or it has came off altogether. If you're running the stock plastic hop unit, i'd suggest you change it out for the metal one. Due to forum rules I can't tell you where to source it from. But they are available out there. It's made by WII Tech.

Make sure if you get it, buy the A&K version. Not the Magpul one

[AhhCool]

Re: A&K Masada range issue

piston is fine

Hop arm seems fine. after the hop rubber the plastic is broken so a metal 1 would be good. however i see no adverse affect on pressure.

all i can see that might be amis is that the nozzle on the cylinder head has no form of seal at he base or tip. also the spring was a little twisted so I've put a bearing spring guide in and new spring. compression of the cylinder and piston is great.

[AhhCool]

Re: A&K Masada range issue

well I've ordered a new metal air nozzle that has a O-ring seal at the base.

[HuntR]

Re: A&K Masada range issue

Which one did you order. As it's not a standard length nozzle

[AhhCool]

Re: A&K Masada range issue

Wii-tech for A&K

[AhhCool]

Re: A&K Masada range issue

well air nozzle has been upgraded. Spring guide has been replaced with one that has bearings, spring has been replaced, cylinder head swapped for double O-ring head. cylinder has been polished and so has the cylinder head and lastly a squirt of silicone spray.

Compression tests are a damn sight better with the new air nozzle however the bb still travels an optimistic 6ft (if that). Hop full on/ mid/ off makes no difference the the travel. First test firing got a stoppage straight away. bb stuck in hop rubber. gave the barrel a clean and pub. got about 6 shots (at 6ft) before another jammed bb. must say though that when i took the mag out I pulled the trigger and a bb shot out of the mag housing with seeming a lot more pressure than the end of the barrel.

New hop required maybe? or could it be that I could do with a ported cylinder? I don't think that suck-back could really affect a bb that much?
However the constancy is miles better since the mods.

[Gaffa]

Re: A&K Masada range issue

Is the hop nub in there (this is the thing that, when you apply more hop, pushes down into the hop rubber to give backspin to the BBs).

[AhhCool]

Re: A&K Masada range issue

yeh looks like a little o-ring that pushes the hop rubber down. yah thats still there. TBH the hop 'looks' to be fine and in working order. but then again so does everything else

[AhhCool]

Re: A&K Masada range issue

well replaced the hop with a wii-tech, replaced the air nozzle with a wii-tech and the bb still flies less than 6ft!

looking at changing the piston next

[Gaffa]

Re: A&K Masada range issue

Too much lubrication on the piston head o-ring causing resistance?

Tappet plate functioning properly? To be honest, I recently sold my A&K Masada which had developed a similar issue and firing at only 220fps, one of the parts I replaced was the tappet plate (along with the cylinder and cylinder head) and this seemed to do the job.

I think my old one must be one of the few with the stock air seal nozzle and hop unit (plastics) without having any cracks in them.

[AhhCool]

Re: A&K Masada range issue

i took the tappet plate off and put it back on and i seem to be back in business (for now) looking at my old air nozzle the ridge where the tappet plate sat was snapped and on my new air nozzle i just didn't put it in the ridge properly

[NinjaAxle]

Re: A&K Masada range issue

have you chronoed the gun to see whether it's an issue with the muzzle velocity or not? also what bbs are you using? I have a problem with a gas pistol firing at 280fps with .25s and it can't reach the end of my garden (10-15m) with the hop fully on, but with .20s it fires dead straight for at least 25m before the bbs start to drop.