• Welcome to the DeeperBlue.com Forums, the largest online community dedicated to Freediving, Scuba Diving and Spearfishing. To gain full access to the DeeperBlue.com Forums you must register for a free account. As a registered member you will be able to:

    • Join over 44,280+ fellow diving enthusiasts from around the world on this forum
    • Participate in and browse from over 516,210+ posts.
    • Communicate privately with other divers from around the world.
    • Post your own photos or view from 7,441+ user submitted images.
    • All this and much more...

    You can gain access to all this absolutely free when you register for an account, so sign up today!

non return valve and 'progressive loading'

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.

Crispin

Spearfisherman ;=- --->
Sep 14, 2001
261
31
118
I've mostly used Cressi pneumatics with a power reducer. I always thought that it was not possible to set the reducer to the reduced setting, load the gun, flick the reducer to full power, and fire the gun at full power. I didn't think the non return valve worked that way. I saw an ad yesterday which said that the power reducer allows 'progressive loading', does this mean that I can do this? (I'm doing a lot more blue water hunting these days out here in NZ, and I could use the extra power).....
 
Read the "pneumatic speargun compression ratio" thread, it explains how the "easy loading" feature works.
 
I was after simple yes or no really pete, *sigh* never mind.
 
Thanks Pete - I appreciate the condensed answer, I did go read the thread, it was very interesting, cheers for taking the time to put those calculations together.
I'm more embarrased that in over ten years of using these guns it's never occured to me to go about using them this way, I'm interested to see how it performs after I add pressure to it, I have a feeling it's going to be fairly impressive. Does anyone else consistently operate their guns this way?
 
Hi Pete,
I too am actually very happy you spelled it out clearly here.
On the Compression thread, it is a bit in the mist for the not so technically inclined. I have read through it a number of times, but the very basics of the easy loading feature is actually not that clear or maybe I am missing it...
But what if one has taken a shot on full power, then would flicking the switch to low power actually help reduce the loading effort at all or would that only work after a low power shot?

Thanks again,
David
 
Last edited:

After a low power shot you only have to put back what you used for that shot, after a high power shot you can load in steps, which means you don't lose the air that went through the non-return valve into the larger front reservoir if you have to let the spear come forwards in the barrel before moving the spear right back to the latch. So you progressively move to the cocked pressure state in the gun with a couple of pushes on the spear, getting the spear futher into the barrel each time. More handy on a long gun than a short one. You leave the selector on "low power" to derive this staged loading advantage.
 
Last edited:
You must log in or register to reply here.
Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…