Iron Ridge Arms:
We are seeing reports of DPMS compatible IRA uppers with some fitment issues with DPMS lower receivers. It appears that when the two parts are mated there is an excessive gap between bolt carrier and buffer. The end result is the buffer gets battered against the buffer retaining pin possibly damaging one or both parts. IRA recommends folks that experience this issue install this buffer pad on the buffer.
Visit the forum for information.
It is my opinion that unless there is a design change if you want an IRA buy a complete weapon from them. Don't mix and match parts.
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