Semi/Auto QDV idea

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MRR
Specialist 3
Specialist 3
Posts: 361
Joined: Tue Feb 17, 2009 2:29 pm

Sat Dec 12, 2009 9:03 am

Recently I watched airsoft videos on YouTube and the blow back mechanism of some guns caught my attention. I googled and after watching some schematics I realized that they are all fake and have nothing to do with the operating of the gun itself.

Disappointing :?

I thought about how to build a blow back that actually work and came up with this idea.

The actual design features a back - forward bolt with a QDV as a main valve.
Image
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The blow forward moves first, due to the weaker spring and has less space to travel than the blow back that pushes back a stronger spring. When the pressure in the "firing chamber" overcame both springs three things happened:
1. the hammer was cocked
2. the QDV closed
3. and the projectile was fired
(in my theory)