Loss of Power and Cleaning questions...

I'm asking these two items together because I *think* they might go hand in hand.

So I went out target shooting with my air gun (non-pal Benjamin Sheridan All Weater .22), yesterday and I noticed what I believe to be a drop off in power.

I came to this conclusion because two weeks ago when I was shooting the gun my brother in law put out some targets (statutues actually that he doesn't want) which I was able to hit, penetrate and blow the pellet through the statue, however, yesterday no such luck.

I hit the statue every time (the precision on the gun is great) but every pellet seemed to get stopped in its track. NO penetration, NO piercing the statue I was able to pierce just two weeks earlier.

The distance remained the same as two weeks ago, but must to be sure, I shot it at about 10, 15, 20, and 30 feet and I still couldn't penetrate it (while I could at about 30 feet two weeks ago). The gun seems to have lost power, so I was thinking maybe it was time to clean it.

I've had the gun for about a month and I've shot approximately 300 pellets through it. I've never cleaned it yet (as I don't know how and the countless "instructional" vides on youtube have left me more confused.

Any thoughts on why the decrease in power and how I should clean it?

Cleaning won't help power, except if it was over lubed with combustibles, but that will reduce not increase power.
So, there are a few possibilities:
1. The high power you got initially was due to dieseling or detonation caused by the action being over lubed. Once the combustibles were burned off you are now getting normal power output from the rifle. Can you post pictures of the target and the damage achieved. I assume you don't have access to a chrony to check precisely (the best way to know it its doing the 460 of fps it should do with normal pellets).
2. It was detonating and has damaged the piston or breach seal. Check the breach seal to make sure its good. It should protrude 0.5mm or so all around the breach surface. Or lay a small piece of tissue over the breach and fire a shot and observe if the tissue gets blown off indicating a leak. If it leaks, shim behind the breach seal so it protrudes and seals properly. I have had a few rifles that this was the cause of low power, but I have a chrony to measure precisely.
3. The piston seal is burned or damaged. You have to pull it down to see. Replace if required.
4. The gas ram is damaged, you can feel this by a greatly reduced cocking effort. Is it easier to cok now than when you first got it? If so... suspect the gas ram is FUBARED.

Good luck. I have gone away from gas rammed Crosmans... I just don't like them. :grumpy:

I agree with everything Duke has told you. It's unlikely that cleaning the gun will correct your issue.

I personally would lean toward Duke's item #3 or #4. But unfortunately the only way to know for sure is have it chronied and tear it down.

If your uncomfortable with cleaning the gun then possibly this isn't going to make you jump for joy ( a lot of us enjoy tearing brand new rifles to bits)

Contact Eric at www.scopesandammo.com

He is a crosman repair center and should be able to better advise you.