Very good. Way better than a drop in conversion kit. So far put about 600 rounds through the 16" and a couple hundred through the 20" with no malfuntions and thats just running standard velocity and some winchester subsonics with a standard milspec trigger. Accuracy is also a lot better than the conversion kits. The 20" is used as a cheap practise set up for service rifle hence the same configuration as my Bushmaster upper.
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