Gas piston & FTE

OZ · September 07, 2003, 00:03

My M444 was having serious FTE today. This is the second time I shot it after replacing the piston and charging handle with USA made ones from Tapco. The piston is mic-ed at 0.426" ... the original piston that came with the gun is mic-ed at 0.431.

So the Tapco piston is smaller by 0.005". Is this enough to cause FTE almost every other round? What is the size of servicable gas piston?

I bought the Tapco gas piston brand new back in 2001. Put it in the parts box and almost forgot that it was there. Did they ever run a out-of-spec batch of their piston ? I did not have a micrometer back then, so I would not know.

colt88 · September 07, 2003, 00:14

You are right, the piston is undersize. Contact Tapco, they will prob. make it good. In the mean time, use the old piston to see if it cycles ok. colt88

Court in Fl · September 07, 2003, 00:14

.426 sounds small to me. Most are around .430 to .429.

Will it work with the .431 piston ?

Court in Fl.

OZ · September 07, 2003, 01:02

Hmm ... the original piston that came from IAI is likely to be non US made part. So I will be in violation of 922r if I use it.

My older FAL also has a Tapco piston that I bought in 2000. This piston is mic-ed at 0.428-0.429 and the rifle works fine with a few clicks left on the gas adjustment dial. I plan to borrow this piston and use it on my M444 to see if it works.

Good idea, I will see if Tapco will do something about this. I still have the original invoice.

larphred · September 07, 2003, 01:42

Yeah, the earliest Tapco pistons were a bit "under spec". Contact customer service and hope for the best. They are a great bunch of guys, even though you are really over the standard return period policy. Good Luck.
If no luck there and you know someone with a lathe and a knurling bar, you can have it knurled to a larger diameter and then turn it down to spec.

OZ · September 07, 2003, 10:07

BUddie says to send it back for an exchange with Tapco's newly designed piston.

Awesome ... I think my problem is taken cared of ...

SSA · September 07, 2003, 13:04

As long as we're talking American made gas pistons here, who makes the Tapco piston, and how many makers of gas pistons are there here in the U.S.? I know of FSE. Any others. Which seems to be the most reliable? Thanks in advance for any good information.

September 07, 2003, 00:03	#1
OZ Registered FALaholic #: 3117 Join Date: May 2001 Posts: 426	Gas piston & FTE My M444 was having serious FTE today. This is the second time I shot it after replacing the piston and charging handle with USA made ones from Tapco. The piston is mic-ed at 0.426" ... the original piston that came with the gun is mic-ed at 0.431. So the Tapco piston is smaller by 0.005". Is this enough to cause FTE almost every other round? What is the size of servicable gas piston? I bought the Tapco gas piston brand new back in 2001. Put it in the parts box and almost forgot that it was there. Did they ever run a out-of-spec batch of their piston ? I did not have a micrometer back then, so I would not know.

September 07, 2003, 00:14	#2
colt88 Registered FALaholic #: 4622 Join Date: Nov 2001 Location: vaughn , wa. Posts: 343	You are right, the piston is undersize. Contact Tapco, they will prob. make it good. In the mean time, use the old piston to see if it cycles ok. colt88 __________________ Hell, I can't be over the hill,I haven't reached the top yet.

September 07, 2003, 01:42	#5
larphred Registered FALaholic #: 1555 Join Date: Nov 2000 Location: Sandy, Ut. Posts: 3,098	Yeah, the earliest Tapco pistons were a bit "under spec". Contact customer service and hope for the best. They are a great bunch of guys, even though you are really over the standard return period policy. Good Luck. If no luck there and you know someone with a lathe and a knurling bar, you can have it knurled to a larger diameter and then turn it down to spec. __________________ Michael O'Sullivan was my great friend. But I don't ever remember telling him that. The words that are spoken at a funeral are spoken too late for the man who is dead. What a wonderful thing it would be to visit your own funeral. To sit at the front and hear what was said, maybe say a few things yourself. Michael and I grew old together. But at times, when we laughed, we grew young. If he was here now, if he could hear what I say, I'd congratulate him on being a great man, and thank him for being a friend. -------------------------------------------------------------------------------- --the forty-four spoke and it sent lead and smoke, and seventeen inches of flame. ----Marty Robbins

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September 07, 2003, 00:14	#3
Court in Fl Curio & Relic FALaholic #: 5046 Join Date: Dec 2001 Location: South Florida Posts: 3,150	.426 sounds small to me. Most are around .430 to .429. Will it work with the .431 piston ? Court in Fl.

September 07, 2003, 01:02	#4
OZ Registered FALaholic #: 3117 Join Date: May 2001 Posts: 426	Hmm ... the original piston that came from IAI is likely to be non US made part. So I will be in violation of 922r if I use it. My older FAL also has a Tapco piston that I bought in 2000. This piston is mic-ed at 0.428-0.429 and the rifle works fine with a few clicks left on the gas adjustment dial. I plan to borrow this piston and use it on my M444 to see if it works. Good idea, I will see if Tapco will do something about this. I still have the original invoice.

September 07, 2003, 10:07	#6
OZ Registered FALaholic #: 3117 Join Date: May 2001 Posts: 426	BUddie says to send it back for an exchange with Tapco's newly designed piston. Awesome ... I think my problem is taken cared of ...

September 07, 2003, 13:04	#7
SSA Registered FALaholic #: 11544 Join Date: Aug 2003 Location: Oklahoma Posts: 63	As long as we're talking American made gas pistons here, who makes the Tapco piston, and how many makers of gas pistons are there here in the U.S.? I know of FSE. Any others. Which seems to be the most reliable? Thanks in advance for any good information.