Both you and 45King basically have it right. Tom Burczynski (Hydra-Shok, Starfire, Quik-Shok, EFMJ designer) explained the dynamics of what a Quik-Shok does (the design principles involved), I’ll try and relate it here. When Tom designed the Hydra-Shok he used a post in the bullet cavity as a mechanism to channel hydraulic pressure to assist the opening of the hollow point. The same principle was used with the Starfire though a different mechanism was used.
While working on these designs and the physic’s involved with hydraulics Tom decided to apply another principle of hydrodynamics – that of if the pressure in a fluid column is raised the pressure in the fluid surrounding that column is also raised – in another design which became the Quik-Shok.
As a bullet enters fluid media that media acts to resist the bullet… this is what creates the initial large temporary would cavity. HPs create a larger temporary cavity because when the bullet expands it has a larger frontal cross-section, which causes greater pressures in the media. However, after a certain point the pressure created will start to subside while the bullet continues on creating its permanent cavity, which also has a very small temp cavity associated along its length. This is why you want to see a football shaped temporary cavity in 10% ordnance gel from conventional HPs.
Now, remember the above principle. What happens with the Quik-Shok is that it acts just like a conventional HP in that it enters the media and starts to expand. When the bullet reaches a certain expansion point the pre-stressed core separate (three segments). Mind you that the separation occurs while the bullet still have a lot of velocity. Due to the HP design of the Quik-Shok each of these segments are of a “quarter moon” shape. Upon separation and because of their shape each segment takes a path that is not parallel to the original bullet track. The segments yaw 180 degrees while continuing along their path.
Now, each one of the segments, traveling at an ever-widening cone is also creating a temporary cavity of its own. So you have three temporary cavities in which the hydraulic pressure in the media is being raised. Hydro physics dictate that the pressure in the surrounding hydro media will also rise. You basically get an over lap of the three temp cavities.
The larger caliber Quik-Shoks display this principle extremely well in Ordinance Gel. The Gel btwn the three permanent would tracks of the segments display fractures. What this translates to in living tissue is that the tissue btwn the three segments would either be destroyed or very seriously damaged. We have cast hearts (non-human of course… gotten from a butcher) in Gel and shot them with conventional HP and Quik-Shok. A conventional HP puts a hole in the front of the heart with a larger hole in the rear. The Quik-Shok literally tears the front of the heart open (in a Y type configuration) due to the above principle with three exit holes in the rear.
Add to the above the benefit of 3 chances of hitting a vital organ and you will come to appreciate the Quik-Shok design.
If you do a search when that function is enabled under the user name “TomBurczynski” you find topics where Tom has explained this much better then I and also results of his hunting experiences with Quik-Shok bullets.
Visuals help with the explanation – go to
Triton Cartridge’s Quik-Shok Page and towards the bottom you’ll see a static picture of a block of Gel just above the table. Click on it and wait for the high-speed video to load (it may take a few minutes) and what the loop a few times.
If you like the .22 Quik-Shok you’ll just love the Center Fire stuff from Triton.
