So fourth time to the range today and my dedicated spikes .22 upper is averaging 2-3 failures to extract per 15 round mag.

 

The gun jams with a new round trying to load and a round still chambered.

 

I have to drop the mag and loose chamber round, close the action and then open it to extract the round on a second attempt...

 

How do I go about trouble shooting this..

 

I notice it happens more with my 12 years old shooting... Could he be "limp writing" the rifle? But it happens too me as well.

 

 

Try changing ammo.

Try changing mags?

I second the ammo thing. You may be using something that isn't strong enough to cycle thru. Also, did you clean and lube before heading out?

 

I would give it 500 or so break in rounds and see how she fares from there. Good luck with it.

 

C

Run it WET with 4-500 rounds of CCI MiniMags and see how it is after that.

There's a thread on ar15.com about tuning your ST-22 upper, they talk about polishing the top side of the chamber and feed ramp, and taking a few turns off the recoil springs as a last resort.

 

But change ammo first. My ST-22 liked the CCI Tactical, and REALLY liked the Velocitors

http://www.ar15.com/forums/t_2_282/189717_ST_22_Semi_and_Full_Auto_Tuning_Guides.html

Thanks... So far I tried two types.. The second type I specifically asked for a hot .22 for use in and AR Upper.

 

I'll post the type whe I get home...

 

 

It is like the extractor is not grabbing the round to extract it... It is leaving a round chambered as if it slipped off the rim or did not engage on to pull out the empty case. The next round strips off the mag but can not chamber since the empty is still in place.