Has anyone had a miss fire like what I will describe????

I loaded my Firebolt, with 90 grains of Triple 7 and loaded a PB 295 grain Aerotip. I left it loaded a few weeks and took it out several times hunting during regular rifle. Didn't see anything worth shooting. I took it out recently and I took off the safety.I was going to shoot it tounload the bullet.I temporarily placed the gun against a tree. I remembered I had the safety off and reached over to put it back on. As soon as I moved the safety to green, the gun went off.

Thankfuly I wasn't hurt, but my ears stung for a while.

Tomster