Does anyone know how to adjust the hammer spring on the Brocock Sniper XR? I thought it would be pretty simple. Took off the stock, and figured out that a 4mm allen went right to what I imagine is the tension adjustment screw. But couldn’t turn it at all either way. Noticed what looked like a small flathead set screw on the side. Loosened that and tried again…….no go. Is the damn thing locktite’d or something?