Very new to airguns/bbs - not sure if airgun seal is bad

[NewAirGunner]

I remember shooting my beretta airgun (.177 cal, 12G CO2 canister) and knowing it does 6 layers of cardboard.

A week later, new canister - as in fresh canister, now it only does 4 layers. Not really the biggest difference, but something to consider.

And going even further back, I just swear that 1-2 years ago I remember that airgun being really really powerful. (Could just be memory playing tricks on me.)

Anyway, i'm very very new to these things and I really only know different calibers, types of pellets (bb vs shaped), feet-per-second, and that there's 2 different types of canisters.

Basically, I wonder if anyone knows if my gun may be underpowered. Shot dispersion even from garage start to garage end isn't that amazing. I'd say that halfway across the garage, shot accuracy is nearly my fist. (I'm not a great shot though)

But the 4 layers of cardboard seems.... off. I just seem to remember the gun being rather terrifying safety-wise in the past, and 4 layers of cardboard truly seeming low.

Any help or advice? is the seal bad?

 

[MikeVV]

There's a lot of things possibly going on.
You don't give much detail, so here's a coupla possibilities.

1 - The CO2 cylinders, can be of slightly different pressures.
2 - The ambient air temperature will have an effect on the CO2 pressure. Warm/hot = more pressure, cool/cold = less pressure.
3 - Guns internal valving wearing, and less efficient than when new.
4 - Barrel dirty.
5 - Different pellets. larger and smaller BB's will effect how the CO2 pressure is distributed as the BB travels down the barrel. Too large, too much BB to barrel friction. Too small, too much gas leakage between the BB and the barrel. Many different possibilities on this one.
6 - See above... Depending on the quality of the BB's, even in the same container, BB's can be of different diameters and even shapes (low quality BB's).
7 - Seals leaking, when the hammer hits the valve, some gas may not be going directly into the barrel.

See #2 again. This is something many don't realize.

There's a few things to investigate...
NOTE - On the BB diameter. Even as little as .0003" can make a difference, dependant on various things.

Mike