I have a couple A1's already but i bought a NIB 907 series 16" AUG. Keep in mind this thing has been sitting un-used for about 20 years.

i'm getting a lot of failure to eject malfunctions, almost like short stroking.

Noticed one thing:  the recoil springs are EXTREMELY tight.  I have to put the AUG to my thigh and pull the charging handle back hard. I believe this is whats causing the failure to ejects/short stroking issues.  When you combine the recoil spring resistance WITH the hammer-pack spring resistance -- then its even harder for the bolt to cycle.

When on "adverse" setting, zero issues.  I shot about 150 rounds of nato ammo through it on adverse and all is good. When i switch to regular setting, the issues begin.

I've left the bolt locked open for a week now and the resistance has not subsided.  I checked the recoils springs, no rust of any kind.  I've oiled them and cycled them over and over plus put about 200 rounds through it. Still hard as hell to pull back.  

What to do?  Keep bolt locked back for 2 months ?  Change the recoil springs? I not really sure how to do that as thrust caps are on there pretty tight.

Any suggestions?

Maybe the ammo you are using isn't hot enough?

Been using all quality stuff, mostly  Federal Lake City 5.56x45mm XM193.  Other stuff has NATO cross on it.

I'd just keep running it on adverse for awhile see if its good to go after a few hundred more rounds. From what I understand about springs leaving it locked back shouldn't do anything because its by going through the whole compression release cycle repeatably that good springs get weaker not just being compressed and staying compressed.

But that wouldn't be the first time I was wrong so if I am im sure someone will come along soon and correct me.

Somethings not right, id send it to Steyr or PJs

Is that the nato version? Mine had jams too. Haven't tried it since
Edit: sorry I missed the part about its a 20y.o. gun

With my two AUGs, locking back the bolt and letting it sit for 2 weeks heled the recoil springs take a set, which made the guns easier to charge. They also seemed to cycle more effortlessly when firing.

Either way, after 1k rounds things should get easier. After 2k it should settle in perfectly.

My experience also.

I agree with Sven. Not sure if it's the factory preservative, or something added later, but I've seen that before on guns that sat a long time. I'd disassemble it and use solvent on all the metal parts, followed by fresh lubricant.

Yup.  Field strip, clean and apply a generous, thin gun oil.  Work action repeatedly....go to range....

I shall give all these tips a try.

Try swapping stocks and bolt carriers between your AUG's and see if the problem follows.

Mick

Interestingly I just found an A1 I forgot I had. It was sitting with the bolt locked back for about five years. Springs have loosened up a bit on it. Going to shoot it today or tomorrow and see how it goes.

Some days I want to be you - today seems to be one of those

Must be nice! 

Was it in the spare garage where the extra Bentleys are?

And be sure you don't oil the recoil springs inside the guide rods.

Bentley's are for chumps. It was in the hangar with the spare G6.

That's good. I thought maybe it was on one of your smaller yachts.