How often do rangers actually ask to see if you have a bear canister? 

I have a Ursack but currently the status is no-go for the JMT.  I’m pretty experienced with bears (have spent many months camping in Yosemite Valley), and I really don’t want to buy a bear canister… but I also want to weigh the risk of getting slapped with a huge fine, or worse, being escorted off the trail.

Yes: see http://thru-hiker.com/articles/bear_canister_bias.php

If you decide you want to carry one but don’t want to buy one, renting is an easy and inexpensive option.  They also have Bearikade carbon fiber models for a little more money than the standard Garcia canisters.

I read that story… but how many times have you been on the JMT vs. that time you were asked… plus you did have a tiny pack which is probably a tip-off.  Thanks for the suggestions!

No problem—good luck and enjoy your hike.

I have been asked if I have a canister but once I knocked the side of my pack and the sound of something hard was heard, the ranger didn’t ask to actually see the container. Of the 10 or so times I have backpacked in the Sierras I was only asked that one time. I also don’t frequent the usual campsites that rangers might be looking to for checking canister compliance. I too prefer using a Ursack but will use my Bearikade now that the Ursack is verboten.

You might out-smart the Ranger, but are you going to out smart that bear?
PS I met three rangers on the JMT, but none asked to see either my permit or canister.