Probably getting into the 1500 round count with my Kriss 45 SBR. I am getting way too many stovepipe and failure to feeds. Some crushing or pushing the bullet into the case. Going to send back to Kriss but wanted to know if anyone else experienced this and fixed the issue on there own. One thing I have noticed is that the top of my magazines are a little ruffed up? I have ten of the extended 28 round mags that I leave loaded. Thought this may be an issue so I broke them back down to 13 round with the same results. Don't mind sending back to Kriss but if it's a fairly easy fix I would rather do it.
Any ideas?

Is this a Gen 1 or Gen 2?

Gen 1

My gen 1 Kriss did the same thing right after I bought it , had to send it back to kriss and they repaired it at no charge , if I remember correctly they replaced the barrel  but it's been several yrs now
Haven't had any trouble since, curious myself as to why yours has started doing same after that round count
Attached File

I have an SBR'd first generation in 45ACP and have never had the problems you describe.  In fact I just shot it at the range today and probably have 5,000 rounds through it so far without any hiccups.  I only load my extended mags to 25 rounds and they run well.

I'm shipping mine back this week. It was nearly perfect until the last two range trips. Hopefully it's an easy fix and Kriss will get it up and running again. There  customer Service had been great so far.