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pedro66
December 17, 2016, 21:00
Recently shortened a Century L1A1 to 18" test fired today had some issues but these were mostly mag related rifle fired pretty well one we got the gas port to the right size (its working at .116) anyway took the rifle apart to clean and the gas piston did not drop free as normal, tunes out that it is now more "S: shaped than just bent, is this a soft CAI 922r part or do I have something else going on?

Thanks

L Haney
December 17, 2016, 21:06
How far was the brass ejecting?

brunop
December 18, 2016, 01:37
Recently shortened a Century L1A1 to 18" test fired today had some issues but these were mostly mag related rifle fired pretty well one we got the gas port to the right size (its working at .116) anyway took the rifle apart to clean and the gas piston did not drop free as normal, tunes out that it is now more "S: shaped than just bent, is this a soft CAI 922r part or do I have something else going on?

Thanks

Probably. I'm also curious how far the brass was ejecting.

4x401
December 18, 2016, 01:47
Lotsa views, little response...guess I'm not the only one biting my tongue..:angel:

4markk
December 18, 2016, 10:34
Can you post a pic of the piston? If it is the old two piece piston that CAI used to use, it is a known faulty part and is trash.

Pluribus
December 18, 2016, 11:49
I would think if it's bent, it's soft. If the piston is of proper temper regardless of barrel length or, gas tube length, gas setting with lots of gas, shouldn't bend. Get another, start over.

me dos centavos which is really worth so very, very little.

:wink:

pedro66
December 18, 2016, 16:35
Sorry for the late reply but Christmas party got in the way last night

I guess we don't need to go over CAI quality issues its been done to death, and anyway not much of the CAI parts remain on this gun but I think this piston was one of them, I have built a few FAL's but never had this happen

Ejection was good etc

http://i445.photobucket.com/albums/qq173/pedro_66/Screen%20Shot%202016-12-18%20at%201.31.15%20PM_zpscg0h6qfr.png

L Haney
December 18, 2016, 16:42
WOW!!!!

pedro66
December 18, 2016, 16:56
WOW!!!!

I know couldn't do it again if I tried almost like I made a machine that was designed to make wobbly pistons

meltblown
December 18, 2016, 17:01
Aww hell is that all? I'd get a hammer and buck it to straighten it out and toss it in the trash.

Interesting

gunplumber
December 18, 2016, 17:08
The thick cylindrical portion (non tapered/egg shaped) is indicative of an FA two piece piston used by CAI. Just toss it in the trash.

pedro66
December 18, 2016, 17:11
The thick cylindrical portion (non tapered/egg shaped) is indicative of an FA two piece piston used by CAI. Just toss it in the trash.

Cool thanks that's what I was thinking but grateful that someone more knowledgeable than I confirms it, I already fitted a surplus item

4markk
December 18, 2016, 19:18
The thick cylindrical portion (non tapered/egg shaped) is indicative of an FA two piece piston used by CAI. Just toss it in the trash.

+1

To the OP, yup, that is the two piece I was referring to. As stated, don't even attempt to straighten it, it is absolute trash. Early reports is that it would shear in half and/or warp.

gunseller
December 18, 2016, 20:41
Now I am going to have to check on mine. I cut one down to 17 3/8. I think I replaced the gas piston but do not remember. Never changed the gas setting or the port size. Shoots way better now than it did before I cut it.
Steve

pedro66
December 19, 2016, 00:46
+1

To the OP, yup, that is the two piece I was referring to. As stated, don't even attempt to straighten it, it is absolute trash. Early reports is that it would shear in half and/or warp.

Honestly there was no way that POS was going back in one of my firearms, although I cannot bring myself to throw it away I will use it a a pry bar or something similar

4markk
December 19, 2016, 08:47
Honestly there was no way that POS was going back in one of my firearms, although I cannot bring myself to throw it away I will use it a a pry bar or something similar

LOL .... ain't gonna pry much. I tossed all mine into the recycle bin, but kept one for reference.

Although this is an old issue, it is good to bring it up once and awhile so others learn about it.

Good luck on the repaired rifle. :beer:

ALL FAL
December 20, 2016, 03:20
Glad ya got it figured out Pedro.

V8Merc124
December 20, 2016, 04:22
Honestly there was no way that POS was going back in one of my firearms, although I cannot bring myself to throw it away I will use it a a pry bar or something similar

Send it to me, Ill make a bottle opener out of it for you, no cut down like I do on the ones I sell.
Nice convo piece, make up all the stories you want as to why its bent.:biggrin:

vmtz
December 20, 2016, 09:08
Sorry for the late reply but Christmas party got in the way last night

I guess we don't need to go over CAI quality issues its been done to death, and anyway not much of the CAI parts remain on this gun but I think this piston was one of them, I have built a few FAL's but never had this happen

Ejection was good etc

http://i445.photobucket.com/albums/qq173/pedro_66/Screen%20Shot%202016-12-18%20at%201.31.15%20PM_zpscg0h6qfr.png

The classic two piece gas piston. I have one stored if you need it. LOL. Get a real one and be done with it. Don't dump it. It is a badge of honor.

Vince

raubvogel
December 21, 2016, 06:27
Hang it over the fireplace