Mod: DIY Shortstroking

So you bought a Hi-capa airsoft gun and you want to tweak it so it's better for IPSC?

That's where I am.

Read on for an explanation of my first ever mod to my hi-capa.

I was reading the internet for easy modifications to an airsoft pistol when I stumbled upon the term Shortstroking.

A short explanation of shortstroking without too much details and science is this: Shortstroking reduces the distance the slide travels when a BB is fired. This also reduces the time it takes for a new BB to load and the gun to reset to a state where you can pull the trigger to fire the new BB. (So it reduces the time it takes for the gun to cycle)

So it actually means you can put BBs faster where they need to be.

Take a look at the following video (this isn't mine, so credits go to the poster):

Ok, so I don't have an airsoft shop where they sell hi-capa upgrades nearby and I wanted to try this using some DIY materials. Looking around for a bit, I decided to buy some metal washers and rubber sealings to get the same effect as commercial options.

I did some research on what size of metal washers would be a good fit and eventually, I found these in my local diy shop:

The specification indicates the hole is 8.4mm diameter, the outer diameter is 16mm and the thickness is 1.6mm. This is a box of 50 and it set me back 2.5€ or something like that. After searching for a while, I couldn't find any good size rubber sealings there, so I gave up.

As luck would have it, the next week my local discount supermarket (Aldi, for those in Europe) was selling a set of rubber sealings for 4€:

It has all kinds of different sizes, and when I got home, I soon found one that was a perfect fit. I can't tell you the specification, as I can't find it on the box.

Ok, so I tried out a couple of setups for my shortstroke mod, but since I want to keep the lock-back function on my replica, I can't add a lot of spacers on the recoil guide rod. If you don't need to retain the lockback functionality, try out some more spacers and you'll see the speed of the cycling increase incredibly.

Time for a before and after shot:

Before

After

By adding 2 washers and a sealing I made the pistol cycle a lot faster and only needed slight modifications on the slide to allow it to lock back. I cut and filed (it's a plastic Tokyo Marui slide) slightly on the rear-most side of the lockback notch in the slide. And now the lockback catch can just slide upwards when the slide is entirely pulled back.

Unfortunately, I wasn't able to retain the automatic lockback functionality when a magazine is empty, since the released gas doesn't blow back the slide far enough for the slide to catch on the lockback lever.

I'm currently waiting for a commercial shortstroke mod I bought from AIP. Once I get it, I'll do another post on that one.

Thanks for reading, and remember kids, if you fiddle around with your toys, their warranty is void!

Source: http://www.youtube.com/watch?v=tFn460nB3vI (2014-02-10)