Low FPS and misfeeding for first 50 shots

Mirodasc · September 18th, 2014, 23:14

Hello, I've got a G&P Fire Pig using PTS 120rnd TMAGs, and if I load to ~100, the first 50 shots or so have super low FPS, or double feeds, or don't even come out of the barrel. After that They work fine.

Happens with my Dytac Invader mags as well.

Anything I should be looking for?

EchoFourTwelve · September 18th, 2014, 23:24

Sounds like a problem I had with my gun. If I'm not mistaken, it is nozzle misalignment. Source: pesto

lurkingknight · September 19th, 2014, 14:47

usually stuff to do with the nozzle... if it doesn't fit the cylinder head tightly, tappet return speed if the tappet attached to the nozzle can't come forward fast enough or is obstructed by friction (rough rails in the gearbox) or objects in its path (trigger shuttle return spring that sits under the tappet could be hit if it's not sitting centered).

BogardusFoul · September 19th, 2014, 21:35

Could be piston is partially shredded and not getting a full stroke.

lurkingknight · September 20th, 2014, 02:04

it would sound pretty nasty if that were the case, if it sounds like it's cycling as normal then it's not the piston.

Mirodasc · September 20th, 2014, 06:17

So I ripped 'er apart tonight, and re-greased it all, and noticed that the plastic teeth on the piston are kind of deformed a little.

I installed Magic Box Hopup bucking, springs, and nozzle.
After that I did a few test shots with a fully loaded mag, and she seemed to shoot just fine.
I will report my findings after I play on Sunday.

lurkingknight · September 20th, 2014, 08:11

you will notice a little deformation on plastic tooth pistons, It's pretty normal, that's wear and tear. You can make the wear more even if you add a sorbo pad to correct the angle of engagement. But at this point I would just read up on AoE and then wait for this piston to fail before fixing it. No point in opening it up again if it's working.

Mirodasc · September 22nd, 2014, 02:33

Gun worked flawlessly after installing upgrades new parts.
Don't know what parts fixed the issue, but I'm not taking anything out to find out.
Not a single shot through 2000 bbs had anything other than what I would call a normal shot.

Issue Resolved.

Styrak · September 22nd, 2014, 11:45

It would be the hopup bucking, or nozzle, or both that solved your issues.

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September 18th, 2014, 23:14	#1
Mirodasc Trader rating Join Date: May 2006 Location: Vancouver BC	Low FPS and misfeeding for first 50 shots Hello, I've got a G&P Fire Pig using PTS 120rnd TMAGs, and if I load to ~100, the first 50 shots or so have super low FPS, or double feeds, or don't even come out of the barrel. After that They work fine. Happens with my Dytac Invader mags as well. Anything I should be looking for?

September 18th, 2014, 23:24	#2
EchoFourTwelve Enjoy's Tight Groupings from behind in his Tight Pants Trader rating Join Date: Dec 2012 Location: Toronto, ON	Sounds like a problem I had with my gun. If I'm not mistaken, it is nozzle misalignment. Source: pesto __________________ Guardians of Asgaard - KF14 "tight pants, tight groups, "

September 19th, 2014, 14:47	#3
lurkingknight "bb bukakke" KING! Trader rating Join Date: Jul 2011 Location: Ottawa	usually stuff to do with the nozzle... if it doesn't fit the cylinder head tightly, tappet return speed if the tappet attached to the nozzle can't come forward fast enough or is obstructed by friction (rough rails in the gearbox) or objects in its path (trigger shuttle return spring that sits under the tappet could be hit if it's not sitting centered). __________________ I futz with V2s, V3s and V6s. I could be wrong... but probably, most likely not, as far as I know.

September 19th, 2014, 21:35	#4
BogardusFoul Trader rating Join Date: Mar 2012 Location: Guelph, ON	Could be piston is partially shredded and not getting a full stroke. __________________ Stabface Custom Embroidery Name Tapes Team Patches Hats Custom Embroidery www.stabface.ca

September 20th, 2014, 02:04	#5
lurkingknight "bb bukakke" KING! Trader rating Join Date: Jul 2011 Location: Ottawa	it would sound pretty nasty if that were the case, if it sounds like it's cycling as normal then it's not the piston. __________________ I futz with V2s, V3s and V6s. I could be wrong... but probably, most likely not, as far as I know.

September 20th, 2014, 06:17	#6
Mirodasc Trader rating Join Date: May 2006 Location: Vancouver BC	So I ripped 'er apart tonight, and re-greased it all, and noticed that the plastic teeth on the piston are kind of deformed a little. I installed Magic Box Hopup bucking, springs, and nozzle. After that I did a few test shots with a fully loaded mag, and she seemed to shoot just fine. I will report my findings after I play on Sunday.

September 20th, 2014, 08:11	#7
lurkingknight "bb bukakke" KING! Trader rating Join Date: Jul 2011 Location: Ottawa	you will notice a little deformation on plastic tooth pistons, It's pretty normal, that's wear and tear. You can make the wear more even if you add a sorbo pad to correct the angle of engagement. But at this point I would just read up on AoE and then wait for this piston to fail before fixing it. No point in opening it up again if it's working. __________________ I futz with V2s, V3s and V6s. I could be wrong... but probably, most likely not, as far as I know.

September 22nd, 2014, 02:33	#8
Mirodasc Trader rating Join Date: May 2006 Location: Vancouver BC	Gun worked flawlessly after installing upgrades new parts. Don't know what parts fixed the issue, but I'm not taking anything out to find out. Not a single shot through 2000 bbs had anything other than what I would call a normal shot. Issue Resolved.

September 22nd, 2014, 11:45	#9
Styrak Trader rating Join Date: Jan 2007 Location: Saskatoon, SK	It would be the hopup bucking, or nozzle, or both that solved your issues. __________________ Airsoft Sales and Repair/Upgrade Services

Low FPS and misfeeding for first 50 shots

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