Just got a new Storm Lake Barrel to run an AAC can on my Pro..

Everything fit well, but darn if it doesn't feed right. Using standard PMC ammo, not subsonic for testing.

Basically almost every round would fail to feed with about 1/2 getting stuck in the ejection port sideways after being fired.

Anyone know of spring adjustments or anything else that might need to be done. I assumed with suppressor sights, etc it would be good to go out of the box, but obviously not.

which suppressor?

Aac evo 9

It sounds like you need to break in the barrel. Sometimes that fixes these issues with drop in barrels. You just need to put a couple hundred rounds through it and then it will start working better.

What grain weight bullet are you using? If you're trying 115gr then I would bump up to 124gr.

How many rounds though this setup so far?

FYI it sounds like the slide is not making it all the way to the rear.

Try stronger ammo for the break in period.

How does the recoil feel? snappy or sluggish ?