HW90 power capabilities?

Recently added a .25 Weihrauch HW90 to my collection. Couldnt wait to get it out of the box and shoot it. I have to say I was a little disappointed in it. I shot 5 or 6 rounds into a pine 1x6 (3/4 inch thick) at a real close distance. Like 3 or 4 feet. It barely buried the silver arrows past the skirts. My RWS 34 will shoot about any .177 pellet clear through the same board. And my Beeman Kodiak with Theoben ram will shoot about any .22 pellet clear through my scrap pine door thats an inch and 1/8 thick. Am I looking at a gun that has a problem? Wondering if the gas ram never got fully charged or has a leak? Or is that about right for this particular model? So far I like how it shoots. Nice and smooth. Seems a little smoother than my Kodiak. I dont have a chrony right now either. 

Thanks

Dan
 
Do you have a chronograph; I'd be interested in the numbers...If I remember correctly the Kodiak in 25 with most pellets doesn't penetrate completely through 1/2" plywood, but it does go pretty deep and it's kind of blown out and cracked on the backside - at about 30 feet. That's for us "scientists" who like test guns on everyday items and try to draw conclusions from the results. My experience is that high power break barrels, whether spring or ram - in the lesser calibers, tend to over penetrate whereas the 25 doesn't, and dumps it's energy into the target. I read somewhere that in India - where they have a lot of rats, professional hunters prefer the 25 in break barrels; again, I'm not sure if that's a rumor. Also, for game the best pellet is the Crow Magnum - if you can get reasonable accuracy out to 30 yards or so... 
 
Ok guys think about this matter like this.

The cross sections of a .177, .20, .22. and .25 are 0.025 sq. in, 0.031 sq. in, 0.038 sq. in, and 0.049 sq. in. respectively.

In other words the cross section of a .25 pellet is twice as large as that of a .177, 1.6 times as large as a .20, and nearly 30% larger than that of a .22.

Well lets assume you are shooting pellets of the same form factor into a uniform medium with exactly the same muzzle energy.

The .177 will penetrate twice as deep as the .25. The .20 will penetrate sixty percent further than the .25 and a .22 will penetrate thirty percent deeper.

Now these are just basic calculations.that put you in the ball park.

Unfortunately the formula which calculates energy squares velocity and so it favors small projectiles traveling quickly over large projectiles traveling slowly. The thing to remember about a .25 spring rifle is that pellets dump a lot more energy inside the target and more quickly. The .25 leaves a wound channel that at least 30 percent larger than the next lower caliber... 

When you hit a nail into a board it takes less energy to pass through the board. When you hit a board with the hammer, it soaks up ALL the energy and none passes through to be wasted.

BE ADVISED this link leads into the hunting section. If you don't want to see dead critters, don't follow it.

https://www.airgunnation.com/topic/bsa-lightening-grt-25-makes-meat/
 
Ok guys think about this matter like this.

The cross sections of a .177, .20, .22. and .25 are 0.025 sq. in, 0.031 sq. in, 0.038 sq. in, and 0.049 sq. in. respectively.

In other words the cross section of a .25 pellet is twice as large as that of a .177, 1.6 times as large as a .20, and nearly 30% larger than that of a .22.

Well lets assume you are shooting pellets of the same form factor into a uniform medium with exactly the same muzzle energy.

The .177 will penetrate twice as deep as the .25. The .20 will penetrate sixty percent further than the .25 and a .22 will penetrate thirty percent deeper.

Now these are just basic calculations.that put you in the ball park.

Unfortunately the formula which calculates energy squares velocity and so it favors small projectiles traveling quickly over large projectiles traveling slowly. The thing to remember about a .25 spring rifle is that pellets dump a lot more energy inside the target and more quickly. The .25 leaves a wound channel that at least 30 percent larger than the next lower caliber... 

When you hit a nail into a board it takes less energy to pass through the board. When you hit a board with the hammer, it soaks up ALL the energy and none passes through to be wasted.

BE ADVISED this link leads into the hunting section. If you don't want to see dead critters, don't follow it.

https://www.airgunnation.com/topic/bsa-lightening-grt-25-makes-meat/

Bingo ! Surface area comes into play. More pellet surface area the more spread out it's energy. 
 
I shot the the Kodiak this evening and here are the results for comparison:

Crow Magnum: 661; 660; 664; 670; 665 - These were older Beeman pellets with the red and black label and they felt loose when inserted into the barrel.

JSB Exact King Diablo 26.39 gr. : 675; 677; 679; 673; 671 - New current production pellets from PA with a tight fit.

I did a screen shot of the data from Straight Shooters, but it has already posted above so no need - thanks. The HW90 is a great gun; if I owned one in 25 I'd be looking at shooting lighter pellets like FTS to help with trajectory...

"...seems like it's too powerful for good accuracy, how does one take a bit off that??.." 

On my RX2 (.22 caliber), at the rear of the compression tube, is a small screw which when removed exposes the high pressure Schrader (sp) valve where you can release air like a tire - you will need an adapter to pump it up again, and I purchased mine from David Slade several years ago; he also recommended filling with nitrogen. I rebuilt my gun when I replaced the piston seal and it was a breeze - no spring compressor needed of course - just let the air out and disassembly is very straight forward - no problems since.


 
I shot the the Kodiak this evening and here are the results for comparison:

Crow Magnum: 661; 660; 664; 670; 665 - These were older Beeman pellets with the red and black label and they felt loose when inserted into the barrel.

JSB Exact King Diablo 26.39 gr. : 675; 677; 679; 673; 671 - New current production pellets from PA with a tight fit.

I did a screen shot of the data from Straight Shooters, but it has already posted above so no need - thanks. The HW90 is a great gun; if I owned one in 25 I'd be looking at shooting lighter pellets like FTS to help with trajectory...

"...seems like it's too powerful for good accuracy, how does one take a bit off that??.." 

On my RX2 (.22 caliber), at the rear of the compression tube, is a small screw which when removed exposes the high pressure Schrader (sp) valve where you can release air like a tire - you will need an adapter to pump it up again, and I purchased mine from David Slade several years ago; he also recommended filling with nitrogen. I rebuilt my gun when I replaced the piston seal and it was a breeze - no spring compressor needed of course - just let the air out and disassembly is very straight forward - no problems since.


Does your kodiak still have the metal spring? My .22 has been converted to Theoben Gas by Airgunwerks several years ago. Oh, forgot to ask fist time what kind of pressure does that ram take in PSI? I have some access to some charging equipment in the shop for nitrogen filled hydraulic accumulators.


 
5 consecutive shots

514–513–518–513–514

Crow

So I took your numbers and did some math. The advertised FPS was 629 with a 17.49 grain pellet. Makes 17.49 ft/lbs. Your numbers average 514.4 with 26.23 grain makes 15.42 ft/lbs if I did math right with conversion charts. Not sure 2 more ft/lbs would make that much difference. I need to get my kodiak shot through a chrono. That thing might just be hotter than I think. 
 
I shot the the Kodiak this evening and here are the results for comparison:

Crow Magnum: 661; 660; 664; 670; 665 - These were older Beeman pellets with the red and black label and they felt loose when inserted into the barrel.

JSB Exact King Diablo 26.39 gr. : 675; 677; 679; 673; 671 - New current production pellets from PA with a tight fit.

I did a screen shot of the data from Straight Shooters, but it has already posted above so no need - thanks. The HW90 is a great gun; if I owned one in 25 I'd be looking at shooting lighter pellets like FTS to help with trajectory...

"...seems like it's too powerful for good accuracy, how does one take a bit off that??.." 

On my RX2 (.22 caliber), at the rear of the compression tube, is a small screw which when removed exposes the high pressure Schrader (sp) valve where you can release air like a tire - you will need an adapter to pump it up again, and I purchased mine from David Slade several years ago; he also recommended filling with nitrogen. I rebuilt my gun when I replaced the piston seal and it was a breeze - no spring compressor needed of course - just let the air out and disassembly is very straight forward - no problems since.


Does your kodiak still have the metal spring? My .22 has been converted to Theoben Gas by Airgunwerks several years ago. Oh, forgot to ask fist time what kind of pressure does that ram take in PSI? I have some access to some charging equipment in the shop for nitrogen filled hydraulic accumulators.


Yes it still has the original spring - and breech seal! Long story about this gun, but it shoots very, very well; I did consider the Theoben gas ram when I talked with David Slade - I think he quoted me $250+S&H with some machining which was not reversible; if I remember correctly. The gun is for hunting - period!

Start at 330-335 PSI; I've shot as low as 325 PSI and the cocking effort at the lower pressure drops of dramatically - along with power so it's not linear. Some say maximum is 350 PSI and some as much as 365, but when you hit 350, you've pretty much maxed it out. The ram runs inside the tube which has two o-rings and a thin back up seal with a counterweight or slug which is held in place with two other o-rings - you've probably seen the diagram. My point is it can burst or the the power can be increased to much so the seal will start slamming into the end of the tube - bad news. I forget now what I finally set mine at 340-345? It's been three or four years and it's still shooting fine and hasn't lost power. 
 
I shot the the Kodiak this evening and here are the results for comparison:

Crow Magnum: 661; 660; 664; 670; 665 - These were older Beeman pellets with the red and black label and they felt loose when inserted into the barrel.

JSB Exact King Diablo 26.39 gr. : 675; 677; 679; 673; 671 - New current production pellets from PA with a tight fit.

I did a screen shot of the data from Straight Shooters, but it has already posted above so no need - thanks. The HW90 is a great gun; if I owned one in 25 I'd be looking at shooting lighter pellets like FTS to help with trajectory...

"...seems like it's too powerful for good accuracy, how does one take a bit off that??.." 

On my RX2 (.22 caliber), at the rear of the compression tube, is a small screw which when removed exposes the high pressure Schrader (sp) valve where you can release air like a tire - you will need an adapter to pump it up again, and I purchased mine from David Slade several years ago; he also recommended filling with nitrogen. I rebuilt my gun when I replaced the piston seal and it was a breeze - no spring compressor needed of course - just let the air out and disassembly is very straight forward - no problems since.


Does your kodiak still have the metal spring? My .22 has been converted to Theoben Gas by Airgunwerks several years ago. Oh, forgot to ask fist time what kind of pressure does that ram take in PSI? I have some access to some charging equipment in the shop for nitrogen filled hydraulic accumulators.


Yes it still has the original spring - and breech seal! Long story about this gun, but it shoots very, very well; I did consider the Theoben gas ram when I talked with David Slade - I think he quoted me $250+S&H with some machining which was not reversible; if I remember correctly. The gun is for hunting - period!

Start at 330-335 PSI; I've shot as low as 325 PSI and the cocking effort at the lower pressure drops of dramatically - along with power so it's not linear. Some say maximum is 350 PSI and some as much as 365, but when you hit 350, you've pretty much maxed it out. The ram runs inside the tube which has two o-rings and a thin back up seal with a counterweight or slug which is held in place with two other o-rings - you've probably seen the diagram. My point is it can burst or the the power can be increased to much so the seal will start slamming into the end of the tube - bad news. I forget now what I finally set mine at 340-345? It's been three or four years and it's still shooting fine and hasn't lost power.

What did the velocity end up topping out at when you went full pressure? 
 
I shot the the Kodiak this evening and here are the results for comparison:

Crow Magnum: 661; 660; 664; 670; 665 - These were older Beeman pellets with the red and black label and they felt loose when inserted into the barrel.

JSB Exact King Diablo 26.39 gr. : 675; 677; 679; 673; 671 - New current production pellets from PA with a tight fit.

I did a screen shot of the data from Straight Shooters, but it has already posted above so no need - thanks. The HW90 is a great gun; if I owned one in 25 I'd be looking at shooting lighter pellets like FTS to help with trajectory...

"...seems like it's too powerful for good accuracy, how does one take a bit off that??.." 

On my RX2 (.22 caliber), at the rear of the compression tube, is a small screw which when removed exposes the high pressure Schrader (sp) valve where you can release air like a tire - you will need an adapter to pump it up again, and I purchased mine from David Slade several years ago; he also recommended filling with nitrogen. I rebuilt my gun when I replaced the piston seal and it was a breeze - no spring compressor needed of course - just let the air out and disassembly is very straight forward - no problems since.


Does your kodiak still have the metal spring? My .22 has been converted to Theoben Gas by Airgunwerks several years ago. Oh, forgot to ask fist time what kind of pressure does that ram take in PSI? I have some access to some charging equipment in the shop for nitrogen filled hydraulic accumulators.


Yes it still has the original spring - and breech seal! Long story about this gun, but it shoots very, very well; I did consider the Theoben gas ram when I talked with David Slade - I think he quoted me $250+S&H with some machining which was not reversible; if I remember correctly. The gun is for hunting - period!

Start at 330-335 PSI; I've shot as low as 325 PSI and the cocking effort at the lower pressure drops of dramatically - along with power so it's not linear. Some say maximum is 350 PSI and some as much as 365, but when you hit 350, you've pretty much maxed it out. The ram runs inside the tube which has two o-rings and a thin back up seal with a counterweight or slug which is held in place with two other o-rings - you've probably seen the diagram. My point is it can burst or the the power can be increased to much so the seal will start slamming into the end of the tube - bad news. I forget now what I finally set mine at 340-345? It's been three or four years and it's still shooting fine and hasn't lost power.

What did the velocity end up topping out at when you went full pressure?

I don't remember exactly, but I think I had to go to 350 PSI to duplicate Straight Shooters results and lowered it to improve accuracy, but it's probably shooting JSB 15 gr in the higher 700's so 14gr crossman around 800.