I think my gamo is losing power

[rmDaffle]

So I got a gamo swarm whisper mach 1 (brand new) in .22 and a prowler in .22 (pretty old).
I believe my mach 1 is around the same power as the prowler, although I just think when I got it (like 1 week ago) it was way stronger.

The mach 1 is like 20-22 fpe and the prowler is maybe at 14 to 15 (I DONT KNOW WHAT MY FPE IS , THATS WHAT I WOULD PRESUME!). I just cant shake the feeling I could've gotten a lemon or theres already a problem. Theres tests I do with my mach 1 now that I feel it used to do better like a week ago.

I put a big fanta bottle, like the general one, and fill it with water. It goes through but doesn't have power to puncture the other one. I have the lids off btw. Is that normal? How does your airgun preform on that.

I'm kinda scared

[Roadworthy]

Did you clean the barrel of the new gun before shooting it?  Was there any sign of dieseling or detonation?  A new gun will frequently have residual oils and "stuff" left over from the manufacturing process.  If there was detonation it would have given the pellet more power until the barrel was clear.  Compare the power of the two guns now.  Shoot it awhile then compare them again.  They should be fairly close.

[mikeyb]

So I got a gamo swarm whisper mach 1 (brand new) in .22 and a prowler in .22 (pretty old).
I believe my mach 1 is around the same power as the prowler, although I just think when I got it (like 1 week ago) it was way stronger.

The mach 1 is like 20-22 fpe and the prowler is maybe at 14 to 15 (I DONT KNOW WHAT MY FPE IS , THATS WHAT I WOULD PRESUME!). I just cant shake the feeling I could've gotten a lemon or theres already a problem. Theres tests I do with my mach 1 now that I feel it used to do better like a week ago.

I put a big fanta bottle, like the general one, and fill it with water. It goes through but doesn't have power to puncture the other one. I have the lids off btw. Is that normal? How does your airgun preform on that.

I'm kinda scared

My Prowler shoots around 16fpe. I don't have a Mach1 Gamo but they appear to be rated 22 fpe BY Gamo. IMO that is likely MAX as most manufacturers use overly optimistic specs. Realistically the Mach1 Gamo will chronograph between 18-20 fpe.

You will NEED to use a chronograph to measure velocity and calculate fpe.

The difference between 16 and 18 fpe will be very subtle unless you use a chronograph.

Many NEW rifles will have excess factory lube. I believe this is done to prevent RUST during extended duration shipping and/or warehouse storage. That factory lube will BURN adding velocity to pellets during the initial break-in period. That could be 50 pellets up to 1000 depending on the amount of factory grease.

What I typically see in "fresh springers" is 2-6 shots of EXCESSIVE grease burning which is VERY LOUD and VERY SMOKEY. Much of the LOUDNESS is the pellet going SUPERSONIC like the CRACK of a bullwhip. Some folks call that detonation and it is a HARD SHOCK to the internal parts. A few shots like that may not cause damage but MANY shots like that will damage the internal parts.

After a few supersonic rounds the "fuel" (grease) begins to burn away more slowly. This is commonly referred to as "dieseling". Rifle will be shooting "hot" but not supersonic. You can SEE and SMELL this phase. Little wisps of smoke lingering around the muzzle or breech and the acrid odor of burnt oil should be obvious.

Both the smoke and the odor will dissipate over time. The pellet velocity will gradually go down and then plateau around where the rifle SHOULD be shooting for a long time.

At that point there is no extra fuel to burn and the rifle is just using compressed air to launch the pellet.

I think your Prowler is where is should be and your Gamo may be dieseling down to where it should be.

Chronograph data is the best way to determine if your rifles are healthy or not.

[Tater]

Moved to the Gamo Gate.

[19Sheridan57]

   I agree with both of the fine gentlemen above.

[rmDaffle]

So I got a gamo swarm whisper mach 1 (brand new) in .22 and a prowler in .22 (pretty old).
I believe my mach 1 is around the same power as the prowler, although I just think when I got it (like 1 week ago) it was way stronger.

The mach 1 is like 20-22 fpe and the prowler is maybe at 14 to 15 (I DONT KNOW WHAT MY FPE IS , THATS WHAT I WOULD PRESUME!). I just cant shake the feeling I could've gotten a lemon or theres already a problem. Theres tests I do with my mach 1 now that I feel it used to do better like a week ago.

I put a big fanta bottle, like the general one, and fill it with water. It goes through but doesn't have power to puncture the other one. I have the lids off btw. Is that normal? How does your airgun preform on that.

I'm kinda scared

My Prowler shoots around 16fpe. I don't have a Mach1 Gamo but they appear to be rated 22 fpe BY Gamo. IMO that is likely MAX as most manufacturers use overly optimistic specs. Realistically the Mach1 Gamo will chronograph between 18-20 fpe.

You will NEED to use a chronograph to measure velocity and calculate fpe.

The difference between 16 and 18 fpe will be very subtle unless you use a chronograph.

Many NEW rifles will have excess factory lube. I believe this is done to prevent RUST during extended duration shipping and/or warehouse storage. That factory lube will BURN adding velocity to pellets during the initial break-in period. That could be 50 pellets up to 1000 depending on the amount of factory grease.

What I typically see in "fresh springers" is 2-6 shots of EXCESSIVE grease burning which is VERY LOUD and VERY SMOKEY. Much of the LOUDNESS is the pellet going SUPERSONIC like the CRACK of a bullwhip. Some folks call that detonation and it is a HARD SHOCK to the internal parts. A few shots like that may not cause damage but MANY shots like that will damage the internal parts.

After a few supersonic rounds the "fuel" (grease) begins to burn away more slowly. This is commonly referred to as "dieseling". Rifle will be shooting "hot" but not supersonic. You can SEE and SMELL this phase. Little wisps of smoke lingering around the muzzle or breech and the acrid odor of burnt oil should be obvious.

Both the smoke and the odor will dissipate over time. The pellet velocity will gradually go down and then plateau around where the rifle SHOULD be shooting for a long time.

At that point there is no extra fuel to burn and the rifle is just using compressed air to launch the pellet.

I think your Prowler is where is should be and your Gamo may be dieseling down to where it should be.

Chronograph data is the best way to determine if your rifles are healthy or not.

I seen videos and it does get 20-22 fpe sometimes. And yes, once in a while, not very often though smoke does come out and sound like it dieseled. Now, the reason I'm concerend is because I've shot the gun with the barrel a bit open like 3 or 4 times by accident. The pellet never got stuck.

[rmDaffle]

Did you clean the barrel of the new gun before shooting it?  Was there any sign of dieseling or detonation?  A new gun will frequently have residual oils and "stuff" left over from the manufacturing process.  If there was detonation it would have given the pellet more power until the barrel was clear.  Compare the power of the two guns now.  Shoot it awhile then compare them again.  They should be fairly close.

I shot them both into wood. The gamo has around twice the penetration. With the prowler I can see the pellet in the wood, but with the gamo I can't. The gamo seems to go about 0.3 - 0.4 inches into the wood. And the prowler goes maybe 0.15 - 0.2 inches into the wood. There isn't much of a visual difference but I can see the prowler pellets embedded. The gamo ones I can just barely see if i shine a light thru it.

My gamo got like maybe a bit easier to cock. It's harder to cock than my prowler. My prowler I can cock it while holding it. My gamo I have to rest it on my leg.

Now, my prowler is kinda abused. I've dieseled it with vaseline, it's gotten wet, probably very rusty inside. I think it shoots 14 fpe maybe. I think I saw video saying it shot like 620-650. But in videos the gamo does 800-820.

What are your thoughts? Is 200 fps a big noticeable difference in .22 or is it just subtle? Do you guys have any tests I can preform without a chronograph to see the difference?

What really not worthy is that I think I lost the warranty papers on my gamo, i dont know if It even came with one (I forgot). I also lost the manual. I was able to register it via the serial number.

[Tater]

Moved back to the Airgun Gate as it's a comparison.

[rmDaffle]

Moved back to the Airgun Gate as it's a comparison.

Jerry, what homemade tests can I do to compare power

[avator]

Telephone book. Shoot both guns in and count the pages.

[rmDaffle]

Telephone book. Shoot both guns in and count the pages.

Thanks. Any other more primitive stuff? I know mines can go through a 3/4 board (not that hard, just furring plank) then go through a aluminum can (like the ones that come with chocolate powder). Do you think thats good?

[22Talon]

Not a machanical expert or piston shooter.
But from what i remember the above sounds about right from what i learned back when i did use piston guns.

I recommend buying a chronograph.
They are easy to get and cheap now compared to when i started shooting airguns 20 something years ago.

You can get a basic one off amazon for like 20 bucks. It clamps on the barrel or you hold close and shoot through it.

Not fancy and probably not the most accurate  and limited to like 1200fps readings.

But it should give you a decent ballpark of velocity and consistency.