Hi-capa failure to return to battery

[Roentengen]

I recently aquired a KJW Hi-Capa with an intermittent issue where the outer barrel is too far forward when the slide has returned. All parts are stock KJW and I believe the gun has been moderately gamed.

When the failure occurs it causes the outer barrel to protrude 2-3mm further than normal out the front of the slide and a simillar gap between the rear of the outer barrel and the opening of the slide. The slide is in the correct position and the friction between the outer barrel and the slide is sufficent to prevent the action from cycling. The next shot causes the remaining gas in the magazine to vent. It can be returned to the correct state by lightly striking the front of the outer barrel.

I examined the pistol in as much detail as my minimal experience allowed.

-There are no obvious areas of wear.
-When cycled manually it is smooth with no catching or sticking.
-The most obvious points of wear on the outer are the 2 points of contact where the bushing supports the barrel.
-The lugs on the slide have a little wear that has softened the corners and the grooves in the outer barrel appear to be square.
- the loading nozzle is lubed and moves freely. There are no marks indicating an impact with anything.


It happens intermittently when firing but can be reproduced reliably by using the slide release with the pistol pointed upwards. Mag in or out does not make a difference

Some of the fixes I have considered are

1. A new slide and/or outer barrel seems the most obvious possibility. Also potentially the most costly.

2. A stronger recoil spring. I'm unsure of this one.

3. Replace the barrel/Hop up combination.


Any assistance in solving this would be appreciated.

Thanks in advance

[Thenooblord]

there is an expensive solution, and a more expensive solution, talk to illusion, he can do a stationary barrel that will prevent the jams, or a spring loaded barrel setup that will also prejent the jams. either way, its upwards of $150

[Slono]

Or another super expensive solution...

Get TM hi capa.

Kidding, check both disconnector pieces (the metal bouncy pieces that poke up at the rear of your gun) to make sure they're springy. See if the slide catches on either of those two things.

[ILLusion]

This is caused by the crappy tolerances between the slide and the barrel. Over time and use, the barrel eventually chews through the lugs in the slide that are used to engage the chamber and pull it back. Once the lugs are worn down and the slide can no longer reliably grab & pull the barrel back, the slide ends up getting caught on the top of the chamber, which dramatically increases the damage to the slide.

At this point, there are three solutions, but only two of them are reliable:

1. The first solution is to get a replacement slide. If you get a KJW one, this problem may happen again. If you get any other brand of slide, it may not play well with your barrel, AND/OR if you are able to get the slide to cycle the pistol properly, the barrel may again, chew up the lugs in the slide. This is not a positive, but based on the lack of information in this area, and based on the prices of a quality aftermarket slide, it's best not to guess with this one.
   However, as Thenooblord has pointed out, there is a second and third solution.
   
2. The second solution, is a two piece outer barrel system, pre-loaded with a spring - it's a custom modification that I figured out a couple of years ago before any other solutions were on the market. If you dig around enough, you may find some tutorials or pictures online of how such a setup looks. Basically, it is a two-piece barrel system, with a spring attached to the inner barrel and levers it against the chamber. The outer barrel just covers the assembly. The result, is that the natural state state of the outer barrel, is now to pull backwards, rather than rest in a neutral state. By doing so, the barrel & chamber does not rely on the slide's lugs to pull it back anymore, instead, the spring does this for the slide and the end result is a barrel that (on its own power) follows the slide back naturally. The downside to this, is that now the slide's forward lug now bears the force of returning the barrel to battery AND pushing the spring forward at the same time. If this lug is still in perfect shape, then this shouldn't be an issue, but it WILL take more damage and break down faster. It shouldn't be too much worse, since the spring should only be light weight. However, if that lug is destroyed, then your only reliable option is the third solution...
   
3. The third solution is ILLusion Kinetics fixed barrel, which offloads all contact that the slide makes with the barrel/chamber, which increases the slide life to an infinite level. Even a completely internally destroyed slide can function properly with this barrel set. The barrel does not move, it does not tilt or rock. It's stationary. The chamber top is lowered a slight bit, so that the slide just glides over the chamber cover. This type of barrel works with any brand of slide, regardless of its health.