Feeds are broadly useful ways to share your blog posts, and I make use of feeds in some of the tricks in this blog.
Unfortunately, Blogger keeps messing with them.
In 2011, Blogger started paginating its feeds at 500 posts The entire feed was still available, but in chunks. You had to hack the url parameters to get the whole feed, one 500-post segment at a time.
Recently, Blogger ratcheted that down to a mingy 150 posts per chunk, a real pain in the neck for some of us who have been cranking out blog posts for a while. (Don't snicker: I have been very busy on my main blog.)
However, there is an alternative feed for your blog that still goes up to 500. If you use your entire feed the larger size can be a lot easier to work with.