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Sib
September 26, 2001, 18:27
Thanks for the help so far.I looked at the piston in the tube a little more carefully and I can see what looks like the carry handle protruding into the gas tube. This seems to be where my piston hangs up. I drifted out the pin in the gas block. What do I do from here to remove the tube?
I didn't want to force anything. Thanks again.

I bought a supposedly unfired sar 4800 (looked unfired to me). First time out and I have an extraction problem. I tried the 4800's piston in my sar 48 and it doesn't bind at all. I can't even drop either one's piston down through the tube of the 4800. Binds up big time. When I had the extraction failures, it was all I could do just to pull the bolt back to get the spent shell out. Is the 4800's gas tube the problem or could it be the radway green ammo (ordered some Hirt. just in case). Am I into a problem that I should have a gunsmith fix? I've never tried to build a rifle and don't want to damage anything. TIA for any help.

[ September 26, 2001: Message edited by: gary.jeter ]

[ September 28, 2001: Message edited by: Sib ]

rschimmelbusch
September 26, 2001, 19:48
Sib wrote:
> I bought a supposedly unfired sar 4800
> (looked unfired to me). First time out and
> I have an extraction problem. I tried the
> 4800's piston in my sar 48 and it doesn't
> bind at all. I can't even drop either
> one's piston down through the tube of the
> 4800. Binds up big time.
Sounds like the forward end of the 4800's tube is pinched inward by screwing it into the gas block too hard. You might pull it out and check. Carefull though, trying to spread the ends usually results in splits at the drift pin flats.

To remove it, drift out the pin in the gas block underneath where the tube threads in to the block.


> When I had the extraction failures, it was
> all I could do just to pull the bolt back
> to get the spent shell out.
That's pretty typical. It's been discussed in the past, I don't rember if its a rough chamber wall issue or failure of the brass to "un-obturate," or what.

> Is the 4800's gas tube the problem
Probably. The piston should drop through freely in there.

> or could it be the radway green ammo
> (ordered some Hirt. just in case).
RG should function with gas regulator all the way closed.

> Am I into a problem that I should have a
> gunsmith fix? I've never tried to build a
> rifle and don't want to damage anything.
> TIA for any help.
Are you feeling lucky??!! It's really not critical/dangerous, you just need to identify the propblem and wield the proper sized punch carefully if that is what is necessary. You aren't headspacing here...

HTH,
Rich

W.E.G.
September 26, 2001, 20:39
Big discussion of FTE at http://www.l1a1.com/cgi-bin/forums/ultimatebb.cgi?ubb=get_topic&f=3&t=002574

Sib
September 28, 2001, 18:29
BTT

EMDII
September 28, 2001, 19:01
Also, check the barrel timing VERY carefully. Drag on the handle pivot /gas nut would indicate mistimed.