I keep seeing ads for entry level offerings from the typical online vendors, Palmetto & Bear Creek that typically have 1:7 twist barrels. I see that the overwhelming majority of ammunition, especially at the lower price point, in both .223 Remington and 5,56 NATO are usually 55 grain FMJ. Wouldn’t logic dictate a slower twist barrel for these light bullets? I have to look pretty hard at these websites to find barrels with 1:9 twist, so what’s up with that? Is it cheaper to manufacture a fast twist barrel?