Tuning a Mrod for 2,000 psi

[KenH]

The Mrod comes tuned for an average of 2500 psi.  For more efficient air consumption I understand it is better to tune for..... say 2,000 psi?  This seems like a good idea when using a scuba tank of 3,000 psi - won't be but a very few fills before scuba pressure is well below 3,000 psi.

I've read about tuning using a chrony - but is there a decent way to tune without a chrono?  If tuned for 2,000 psi, would it be ok to fill the first few fills from fresh tank to 3,000 psi?  OR would it be best to hold fills to 2500 psi for a tuned 2,000 psi setting?

Is there a reasonable number of turns on each setting that could work without a chrono?

Thanks again for all the help - I'm sure learning a LOT from ya'll.

Ken H>

[Markez]

I tuned my .22 Mrod for 2000psi fills so I could get more fills out of the scuba tank plus I do not need
full power in my small back yard. I would not try it it without a chrony because you need to look at
the curve of the shot string to keep your efficiency. You can tell you are close by the sound of the
gun but 1/4 - 1/8 of a turn in the adjustments can make all the difference.

I always fill to 2000psi or less with the gun adjusted that way.

If you are going to try it download the "A Teams" tuning guide to get you started.

Mark

[rsterne]

If you tune the gun to shoot properly from 2000 psi down to say 1000-1200.... and then fill it to 2500.... the velocity will be much less.... At 3000 psi the valve may lock completely and the gun not even fire....

Bob

[KenH]

Thanks for the info - I knew I had read never to fill much past the tune psi point, but didn't fully understand why.  Now I do.

I will get the "A Teams" guide and do some more reading....  I was thinking a decent tune for lower pressure required a chrono but wished to confirm.  Hey, an excuse for another purchase:)

Ken H>