How airsoft and BB gun magazines work

by Tom Gaylord
Writing as B.B. Pelletier

Today’s report is another guest blog from reader Ian McKee who writes as 45 Bravo. Today he tells us how airsoft and BB magazines work.

If you’d like to write a guest post for this blog, please email me at: [email protected].

Okay — take it away 45Bravo!

Ian McKee
Writing as 45Bravo

How Airsoft and detachable BB gun magazines work

This report covers:

  • It’s a replica thing
  • Low/mid capacity
  • Most of them are very similar
  • Magazine capacities
  • High capacity
  • It’s high capacity clockwork!
  • Summary
  • Coming in the future

It’s a replica thing

A lot of replica air guns have removable magazines to replicate the look and function of the actual firearm they are copied from. 

magazine lineup
From left to right, is a real 5.56/.223 30 round magazine, a 70 round mid-capacity mag, a “20 round” mag that actually holds 150 rounds of airsoft ammo, a 300 round mag, and a 850 round “fatmag”.
read more


SigAir ProForce MCX Virtus AEG airsoft gun: Part 5

by Tom Gaylord
Writing as B.B. Pelletier

Virtus AGE right
SigAir ProForce MCX Virtus AEG right side.

Part 1
Part 2
Part 3
Part 4

This report covers:

  • 110 mainspring
  • BUT
  • Prediction
  • Changing the mainspring
  • Assembly
  • Performance
  • 0.20-gram BBs
  • Rock and roll
  • 0.25-gram BBs
  • Battery
  • Summary

Today we’re going to have a little fun. I know some of you would like to work on spring-piston airguns but you just don’t want to jump into the deep end of the pool — as in buying expensive tools like a mainspring compressor and parts that may or may not work as you expect. Today we are going to change the mainspring in the SigAir ProForce MCX Virtus AEG airsoft gun, and we will do it with two Allen wrenches — nothing more! This is a job any of you can do. Then we’ll test the velocity of the gun and see what impact the new spring has made. read more