Apex Extra Power Magazine Spring Set

This magazine spring set provides increased cartridge lift force during the feed cycle and improves slide-lock-back reliability on the final round. Designed for shooters experiencing weak last-round hold-open or inconsistent feeding with extended or high-capacity magazines, these springs address the root cause: insufficient spring tension near the bottom of the magazine. Manufactured from Rocket Wire in the USA to the kit’s specifications, they are intended for use with specific magazine platforms where standard springs lose tension under extended use or extended base-pad configurations.

Compatibility

• FNX-45 magazines with an Apex Magazine Extension installed
• Apex 19-round magazines for the SA-35 Series Pistols
• Not recommended for the Apex 17-round magazine
• Not recommended for factory SA-35 15-round magazines

Key Features

• Rocket Wire construction – high-tensile, fatigue-resistant material for consistent spring rate over extended service intervals
• Increased cartridge lift force – improves feed reliability, especially with the last 2–3 rounds in the magazine
• Enhanced slide-lock-back function – ensures positive engagement of the slide stop when the magazine is empty
• USA-manufactured to the kit’s specifications by a selected spring supplier

Install Difficulty

Difficulty: 2 out of 5
Tools needed: punch or small flathead screwdriver, magazine disassembly tool (optional)
Estimated time: 5–10 minutes per magazine. No permanent modification to the magazine body required.

FAQ

Will these springs work in factory SA-35 15-round magazines?

No. These springs are designed specifically for the Apex 19-round SA-35 magazine body. They are not recommended for factory 15-round magazines or the Apex 17-round magazine.

How does Rocket Wire differ from standard music wire?

Rocket Wire is a high-carbon, high-tensile alloy with superior fatigue life compared to standard chrome-silicon or music wire. It maintains consistent spring rate over more compression cycles, reducing the need for periodic spring replacement in high-round-count applications.

Will this spring cause over-insertion or damage to the magazine catch?

No. The spring dimensions are held to the same overall length and coil count as the original factory spring. The increased force is achieved through material properties and wire diameter, not through increased pre-load or coil bind. No modification to the magazine catch or frame is required.

All orders ship within one business day. This component carries a limited lifetime warranty against manufacturing defects. No returns on installed springs.