Smyth Busters: Large-Caliber ARs Need Heavy Hammer Springs?
This "Smyth Busters" episode debunks the myth that large-caliber AR-15s require heavier hammer springs. The video explains that cartridge size is irrelevant to hammer spring force and that primer hardness is the key factor. It explores how this misconception might have originated from issues with over-gassed guns or unreliable ignition with certain ammunition like 7.62x39mm. Ultimately, the video concludes that a standard AR-15 hammer spring is sufficient for most large-caliber applications, unless dealing with difficult primers.








