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4/17/2005 4:45:29 AM EDT
I have a SAR-1 (CT "AW" registered) with a perplexing problem.

It has worked fine for about 500-1,000 rds and suddenly, stopped working relibaly.
I've tried all the A-B-Cs to no avail. (ammo, mags, cleaning, parts swapping with another SAR-1
that functions fine and cannot find the source of the problem.

The other SAR-1 (also CT registered) in which parts were swapped, continued to work fine with
my SAR-1s mags, bolt, bolt carrier, piston, etc. Mine continued to malfunction with the other SARs parts as well as its original parts.

The hammer is not peened too badly (yes, it is the crappy Century hammer and internals), same
as the other SAR-1 (which has had 5x the use and abuse of my own).

My SAR-1 will function fine for about ten to fifteen shots then suddenly, either the bolt will lock
open in the middle of a mag-full of ammo, requiring it to be pulled back and released again for the rest of the mag, or the other nastier malfunction is a really bad FTF with the bullet being tipped nose up into the 12-o'clock position jammed against the outer edge of the chamber while the casing gets gouged and dented from the force of the bolt carrier coming home.

Again, I have tried different mags, different ammo; gun is clean - it is getting gas because it doesn't malfunction all the time; all to no avail. Again, I can swap mags and bolt/piston/carrier assemblies between two SARs and my SAR will continue to malfunction and the other SAR won't.

What the heck is going on here?

Thanks in advance,

Steve
4/17/2005 7:00:08 AM EDT
[#1]
I'd make sure the gas port into the barrel is clean.  If that is partially clogged, it could be letting just enough gas through to work most of the time.  It sounds like it's short stroking and that is normally caused by not enough gas into the piston.  

Is your gas block canted?  If so, the extra friction between the gas tube and piston (from slight mis-alignment) could be part of the problem that would show up with weaker ammo.  
4/20/2005 7:12:41 PM EDT
[#2]
The gas port is very clean. I haven't noticed any canting of the gas block, although I have heard this was an issue on some SARs.

The amazing thing is how the malfunctions simply appeared out of nowhere one day and I have not been able to diagnose the problem.
4/21/2005 7:37:05 AM EDT
[#3]
Here's a thought.

Did you swap recoil springs around too? If not maybe your's is getting soft, or weak, as it heats up.

Do you have one of the rubber recoil buffers? Have you tried ditching it, if you do?

Good luck, man.
4/21/2005 11:48:34 AM EDT
[#4]
Is the hammer hitting the bolt carrier too hard?  Bent rail?
4/21/2005 3:02:14 PM EDT
[#5]
Yes and yes.

We swapped the recoil spring assemblies, bolt carriers, bolts, pistons & mags.

Mine continued to malfunction even with another SAR-1s parts. The other SAR-1 functioned flawlessly with the parts from my SAR-1 in place.

I had a recoil buffer in for about a year, one of the semi-clear off-white colored ones. Removing
it made no difference at all.

Bear in mind, my SAR-1 has had about one FIFTH of the "use and abuse" of the "control group"
SAR-1 belonging to a shooting buddy. (both are registered as AWs in CT).

I'm thinking it has to be a gas system related problem that no one who has examined and/or shot
the gun has discovered, or something mechanical, like a burr that is snagging the free travel of
the action. Why else would the rifle "lock open" in the midst of shooting a mag full of ammo?

The other nasty, FTF I described above almost sounds like a short stroke - suggesting a gas system problem, but the clincher is: it doesn't do that consistently and there are obvious signs of
gas leakage anywhere.
4/22/2005 5:18:15 PM EDT
[#6]
How smoothly does the bolt carrier move?  If it does not move easily (with the exception of going over the hammer), make sure the reciever rails are lubed some and there are no burrs or peening on the rails.  That would tend to squeeze and slow the bolt carrier down.  It really does sound like a gas problem though.  

How are you sure the gas port is clean and not partially plugged?  Have you actually pushed something through it and seen it sticking down into the barrel?  

Is there a wild chance that the gas block has rotated slightly and the gas port in the barrel doesn't line up perfectly with the gas block anymore?  yeah, I know it's a longshot, but something seems be keeping gas from going where it's needed.  

When you figure this out, post the problem and solution.  
4/25/2005 1:31:05 AM EDT
[#7]
Again, yes and yes.

The gas system is squeaky clean. There is no dragging or binding that I can tell on operating the
action (slow hand cycling)

I think something suddenly warped itself out of spec. This gun was working fine for almost three
years (and very light usage at that) and suddenly craps out.

The SAR-1 I am comparing it to, which belongs to a shooting buddy, has had about five times
as much ammo through it as mine and has been subjected to much more rapid fire and heat
than mine does. And that one continues to work fine, regardless of whether it has my SARs parts in it or not.

I noticed on mine, I'm having a helluva time trying to lift up the little tab thingy that holds the
upper forearm in place to clean the gas system.
4/29/2005 2:39:55 PM EDT
[#8]


I noticed on mine, I'm having a helluva time trying to lift up the little tab thingy that holds the
upper forearm in place to clean the gas system.



That would be normal, on mine anyway.
5/2/2005 12:29:11 AM EDT
[#9]
Use the slot in the cleaning kit housing as a "wrench" on the lever.  Works like a charm.
5/2/2005 4:56:41 PM EDT
[#10]
Here's my 2 cents . . .

Replace the fire control group -- hammer, disconnector, trigger.  

And I'll tell you why . . .


Just finished building a Romy kit on a OOW reveiver.    Everything AT FIRST seemed to be O-K.

But then - - - the bolt would "lock back" every now and then.  What I discovered was the very tip of the hammer was catching on the bolt carrier (installed a cheap Century group until I can pick up a G2 group)

Installed the G2 group and very thing now runs GREAT  !

Might want to give it a try . . . .
5/3/2005 2:30:27 AM EDT
[#11]
Good point - and I have wondered about that. The only thing preventing me from doing it is I have not diagnosed the cause of the problem and would hate to go out and spend $85 on Red Star or
something similar only to find out that isn't the problem.
5/4/2005 5:01:40 AM EDT
[#12]
SORRY  ! !   SORRY  ! !   SORRY  ! !

I said "hammer" and I should have said  "trigger"  ! !

The tip of the trigger was catching on the bolt carrier -- the part that sticks-up on the left side of the trigger  ! !.

Replace the entire FCG (hammer, trigger, and disconnector) and now everything runs fine.  

Tapco, and a few other places, offer the "G2" FCG for about $40.  Not as good as a Red Star but much better then the Century stuff . . . . .
5/5/2005 8:31:53 PM EDT
[#13]
I imagine that will be my next step.

However, before I do that....I think a real 'smtih' who is experienced with this model rifle should
go over it, first.

Does Josephs' in New Britain do this? I know they work on ARs but I don't know anyone around here who works on "AKs".
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