Runs like a champ - Stern Defense SD BU40 Bolt Carrier

WAS having the same problems as the other reviewer because at first ibhad ordered the barrel in as going to use here on o.p.... after the 5th and 6th time the projected shipping date was changed to a month later(and I. Still not entirely convinced funds weren't removed because the item had not shipped, I got a barrel from n.f.armory... cut in a very slight feed ramp, with a new frontier upper reciever and cheapo matrix arms handguard+10oz kvp tungsten buffer weight, this thing runs like a champ, either i got lucky or all those horror stories with everyone else and this platform paid off because it runs great, but the 10oz buffer weight was CRUCIAL to avoid feeding issues. Great product functions perfect and locks back every time.