Hatsan NeutronStar

[Long_Gun_Dallas]

You know, I thought it adjusted the same as the AT44's.  It's been a while since I had mine apart, but I thought I had backed it off a bit because it was shooting so hat.  It's still shooting hot, and I thought I backed it off as far as it would go, so if there an adjustment, it's not much!

Hmmm.. I havn't looked or tried yet.

I thought I recall people saying the nova had external hammer adjustment?  (not nova star) Or at least adjustment that was accessible without having to remove the stock?  I figured the star would have had the gesture, too.   

I imagine I'll be cutting my hammer spring a bit.  Might save the wishbone debouncer from grenading.  It seems some people have an issue with that, and others don't.  I havn't been able to dig up a real root cause for that failure.    But I figure I'll resolve it when/if it comes to it.

I figure maybe they're failing because Hatsan is cranking their guns up so hot, because that's what's selling?  More tension, pressure, impact.  Launch a hammer at a high pressure valve as hard as you can, and then try to use some forks riding on a pin in the receiver block to catch it real quick.  Either the fork(s) is/are tearing up, or the pin they ride on is destroying people's receivers. 

[Rallyshark]

There is a hammer stop screw, which always ends up beat to death.  You can get rid of that and put a piece of 1/10 scale nitro rc car fuel tubing in a loop between the brass and hammer.  That will provide a stop and a buffer for the hammer.  It will significantly quieten the shot cycle and aid a bit in efficiency.  I did that mod to AT44s with great results.  The hammer spring is adjustable, just like the one on an AT44.  You have a stop hole that you insert something into to keep the hammer from spinning, then you use a long 4mm allen through the rear to adjust the HS with the grub screw inside the hammer.  It is a little counter intuitive, so CW decreases speed and CCW increases speed

Some of the stocks come with a hole already in them to insert something to stop the hammer from rotating while adjusting, and some don't.  I can't remember which ones do and don't though.  You can just take the two screws out of the stock, remove the action and adjust it that way.  It does take a rather long 4mm allen to reach that grub screw in the hammer, fyi. 

[Rat Sniper (AKA: PaulT58)]

One of the first things I did when I got it was replace the 2 piece debounce part with the one that's riveted together.  Thus far, no problems!

[mb94952]

There is a hammer stop screw, which always ends up beat to death.  You can get rid of that and put a piece of 1/10 scale nitro rc car fuel tubing in a loop between the brass and hammer.  That will provide a stop and a buffer for the hammer.  It will significantly quieten the shot cycle and aid a bit in efficiency.  I did that mod to AT44s with great results.  The hammer spring is adjustable, just like the one on an AT44.  You have a stop hole that you insert something into to keep the hammer from spinning, then you use a long 4mm allen through the rear to adjust the HS with the grub screw inside the hammer.  It is a little counter intuitive, so CW decreases speed and CCW increases speed

Some of the stocks come with a hole already in them to insert something to stop the hammer from rotating while adjusting, and some don't.  I can't remember which ones do and don't though.  You can just take the two screws out of the stock, remove the action and adjust it that way.  It does take a rather long 4mm allen to reach that grub screw in the hammer, fyi.

I just got my new Nova Star .177 (New Old Stock) today. I got a screaming deal from Amazon. I guess it was a one day blow out sale or something.
Anyway, I also have the AT-44 and it's probably one of my all time favorites. I shoot it more than my HW100. I'm curious about the fuel tubing mod you're talking about. I have not had a chance to shoot it, yet but it is one of the most comfortable, well balanced rifles I've ever held. It almost feels weightless.

[Rallyshark]

The fuel tubing mod is pretty easy to do.  You just need a piece of 1/10 or 1/8 scale rc car fuel tubing about 2.25" long.  Just roll that up and put it in front of the hammer, and remove that hammer stop screw.  It won't go anywhere, and it will quieten down the shot cycle and possibly help with efficiency(depending on tune).