First, the Ingram cartridges were based on the .223 case with different shoulder angles than the T/CU cartridges....otherwise they were almost identical.
Second, be very careful with that barrel! AFAIK all Ingram barrels used arc welded lugs, and these were known to break under use! Not too pleasant to pull the trigger and watch your barrel take off downrange - happened at a silhouette match I attended. I'm not certain I'd use one, but if you decide to do so, have it magnafluxed first by someone who knows how to do it. Good luck.
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