Hatsan flash all of a sudden loud

[joshuacolvey]

Got to about middle of my 5th magazine and all of a sudden i noticed that it was really loud. Like double loud. Crack and echo and before it was non of that. 



I pulled out the moderator build in peices int he barrel and they are perfect. Same ammo everything is the same. 

 

[wahoowad]

Blown breech o-ring?

 

[joshuacolvey]

Not sure. Now have to tear apart a new gun and see lol

 

[likkitysplyt]

No need to tear it apart … it's the barrel oring … betcha!!!!!!!!!!

 

[Redick]

+1

 

[joshuacolvey]

No need to tear it apart … it's the barrel oring … betcha!!!!!!!!!!

Could you point me at the direction.

 

[joshuacolvey]

Breech deal and the 2 others on that end look great. 

 

[elh0102]

The breech seal that can cause your problem is the one inside the breech. I can't tell from the picture if I'm seeing an O ring or a shadow. If the inside breech O ring is there, look carefully around its entire circumference, as sometimes a small piece may be blown out, and a casual glance will not reveal it. 

 

[cootertwo]

What cal and weight pellet/slug are you shooting. Perhaps the Flash has settled in, and now pushing whatever your firing, past the sound barrier. Thus the "crack" sound.

 

[joshuacolvey]

Breech looks great.


right now just a 14.6 grain .22

 

[Feinwerk]

"crack and echo" sure sounds like the pellet went supersonic or there was no pellet in that magazine chamber and you fired the gun without a pellet perhaps.

The speed of sound can change with the weather. If your velocities were already approaching the speed of sound, there may have been a transition.

If you had any lube contain petroleum distillates on your pellets, there could have been a dieseling effect.

 

[joshuacolvey]

"crack and echo" sure sounds like the pellet went supersonic or there was no pellet in that magazine chamber and you fired the gun without a pellet perhaps.

The speed of sound can change with the weather. If your velocities were already approaching the speed of sound, there may have been a transition.

If you had any lube contain petroleum distillates on your pellets, there could have been a dieseling effect.

No lube or anything on the pellet.


wewther was different so I am hoping to determine that I am just traveling to fast and need to slow her down.


mill know more when I get the chronograph out here shortly.

 

[joshuacolvey]

shots from 200-100 bar with 14.3 grain pellet

now the sound above about 750 ish is like a crack and echo of a 22

Here is a link to the video last shot was about 8 ft away from camera and in the 780-800 FPS range

It’s only a 22 seconds video of last 2 shots

https://share.icloud.com/photos/0GLFFjWVh2sCWb7MTxiWFkF8g#Jonesboro

 

[Feinwerk]

Interesting shot curve. The only balanced portion is shots 40 through 80 where the velocity rises gently to just over 800 ish and then back down to 780 ish. Looks like the first 20 shots or so have partial valve lock with pressure in reservoir too high for hammer spring setting. Have a look at the reservoir pressures for shots 40 through 80 and that's maybe a sweet spot where's your gun is really starting to breathe, but of course it's getting louder. It may be wasting air. Does the hatsan flash have any kind of transfer port adjustment? It might need to be throttled down a little bit with a bit more hammer spring tension to flatten your velocity curve out and get it quieter.

The peak velocities are nowhere near supersonic. Are you sure that your gun is moderated? I'm not familiar with the flash.

 

[joshuacolvey]

Interesting shot curve. The only balanced portion is shots 40 through 80 where the velocity rises gently to just over 800 ish and then back down to 780 ish. Looks like the first 20 shots or so have partial valve lock with pressure in reservoir too high for hammer spring setting. Have a look at the reservoir pressures for shots 40 through 80 and that's maybe a sweet spot where's your gun is really starting to breathe, but of course it's getting louder. It may be wasting air. Does the hatsan flash have any kind of transfer port adjustment? It might need to be throttled down a little bit with a bit more hammer spring tension to flatten your velocity curve out and get it quieter.

The peak velocities are nowhere near supersonic. Are you sure that your gun is moderated? I'm not familiar with the flash.

Listed above is a video of a very well knows gentleman who tests and reviews all sorts of air rifles. The link there is the reference to the exact same rifle int he 900fps range and extremely quite.



The nice spread of shots are from 167-136 bar or 2422 to 1972 psi. Based on the math it uses .8 psi per shot on average. 



I just went pout again with 125 psi in tank and shot 12 shot in my front yard with houses being across the road and such. Every shot there is an echo as well at a crack from each shot.

Also this is a part breakdown. If that adjustment is doable then i have yet to find a video or anyone doing it for sure. Like i said if its in the 700 mid 700 range then it is EXTREMELY quite. above 780 or so its loud. 



Here are 2 quick videos of the sound, crack and echo.

https://share.icloud.com/photos/0luaSJGIkeDkdXfWqYBCcCLjw#Jonesboro

https://share.icloud.com/photos/0gApRz57ICk4INKgB512GlsAw#Jonesboro





Here is the video of the man running 900 or more fps and the sound is dead and quite. More than one video out like this. 

https://youtu.be/R10DsxpImTw

 

[joshuacolvey]

Sent rifle back. New one will be here tomorrow. I was told this is not the first one that had this issue and as far as that goes they do not have a way to resolve the issue but i was not told what the issue exactly was.

 

[bckyrdsnpr52]

I have 2 Flash, one is quiet one loud. I swapped the barrel and shroud from the quiet one to the loud one and it was still loud. This proves the issue is in the action, not the barrel or baffles. I changed orings and made no difference. I bought new baffles, 50 bucks for a couple of hair curlers and felt, ridiculous, made no difference. If you find the fix PLEASE post what you found.

 

[joshuacolvey]

I have 2 Flash, one is quiet one loud. I swapped the barrel and shroud from the quiet one to the loud one and it was still loud. This proves the issue is in the action, not the barrel or baffles. I changed orings and made no difference. I bought new baffles, 50 bucks for a couple of hair curlers and felt, ridiculous, made no difference. If you find the fix PLEASE post what you found.

This makes since with what I was seeing. Mine happens over about 10-15 shots. Louder and louder. Only way for it to not be loud was under 760fps or so. Never found any issues. One thing I did notice was where you take the set screw out from behind the bolt arm when you cocked it it would be partially covered by the shell of the bolt opening.

 

[bckyrdsnpr52]

Its gets louder because the air pressure is decreasing with each shot, allowing the hammer to open the valve easier releasing more air. 

 

[joshuacolvey]

Its gets louder because the air pressure is decreasing with each shot, allowing the hammer to open the valve easier releasing more air.

That’s not the issues. Tank was filled back up as stated above over about 300 shots and never once got quite unless it was under 760fps no matter if it was 200 bar or 100 bar. I could increase and decrease the hammer beyond 760 and below with same results.