I have a a 585 model Ranch rifle and am looking at getting a barrel strut for it, but I have some questions and was hoping to see/hear from others that use this.

My barrel is 18 inches flat and am going to get it threaded soon, and probably get the front iron sight moved back a little bit to compensate. Im uncertain which size strut to get with that consideration. Anyone got experience with these that I can hear from?

My rifle worked fine for a short while but after about the third time taking it out it started jamming. The casing remains stuck to the bolt and fails to eject and causes a double feed jam. I’ve cleaned and checked mags and haven’t found the cause yet