I am not new to reloading. I have been reloading up to a dozen different cartridges, including two wildcats, for about 40 yrs. I have 6 primary hunting rifles that are all bolt action in calibers from .22-250 to .375 RUM. My handloads for all these rifles will shoot MOA or less to 300 yds. Most of my reloading dies are standard (group A) RCBS with also a Horndady and 2 Pacific sets.
I have mostly Full Length resized my cases, but I did make a 0.025" washer to put under the size die to "neck size" the cases. This method does not bump the shoulder, but it does partially size the body of the cases. I have not noticed, or really tested, any difference in accuracy.
My question is: Is this method of backing off the size die and is backing off 0.025" enough to prolong case life?