The 11-coil magazine spring that pairs with the CRS Comp Basepad and the stock SIG follower to reach a reloadable 22 rounds while keeping slide lock-back.
This spring is half of the decision every P226 competition magazine build comes down to. A Mec-Gar 18-round tube with the CRS Comp Basepad can go two ways: an 11-coil spring with the stock SIG follower for a reloadable 22 rounds, or the Grams no-lock-back follower kit for 23. The 11-coil route is the one that keeps the slide locking back on an empty magazine, because it leaves the factory follower in place to trip the slide stop.
The spring is not optional once a longer pad is on. A longer base pad adds internal volume the factory spring was never wound for, and a stock spring in a lengthened tube runs out of travel and starts short-stroking the last rounds. The 11-coil spring restores the travel budget.
Take the 22-round build unless the extra round genuinely decides a stage. Losing lock-back costs a diagnostic cue on every empty gun, which is a real price to pay for one round.
Add the Cascade Range Systems 11-Coil P226 Magazine Spring to your build and see how it enhances your platform.