Thank you to those who gave me the benefit of the doubt and helpful advice. My problem was resolved with a combination of squeezing both sides of the trigger guard and jiggling the key repeatedly. Both keys now work perfectly. I think I had just squeezed too tightly when I locked the trigger guard, and since it works just as well when not squeezed so hard, I won't do it again.
I realize that you're not a help line, which is why I searched all of your forums thoroughly using key words before asking my question. I got only a couple of hits, and they didn't address my problem or even apply to it, so I went ahead and posted a question that I suspected had an easy answer -- easier than walking into a locksmith's shop carrying a revolver anyway...
Just FYI -- when I first entered my original inquiry into an external search engine using the words "Master lock key P250", I got a couple of images of trigger guard/key combinations that looked exactly like mine -- that's what convinced me that I had the right keys, although I now understand that they're the same template as the keys that open some master padlocks (although not my Master padlocks). I was almost certain they were the right keys from the beginning because I keep track of my stuff, and found them where I expected to.
BTW -- your site was the first one listed after the images of the trigger guards, so I can understand that you get lots of questions like mine and that you get sick of them.
In my defense, I did say in my original post that keys would go all the way in, but would not turn,
"The keys both go all the way in, but they just will not turn."
So, thanks again for the advice, the benefit of the doubt when given, and the grace to apologize shown by mseifert.
All's well that ends well and please remember to be kind to newbies
Don
