Hi,
I'm shooting a C. Sharps 1885 in 38-55.  320gr tapered bullet, breech seated ~18.0gr IMR-4227 in a single case.   Average velocity 1324 fps.

As the morning wore on, extracting my case started to get tougher.  I didn't think it was making a lot of pressure as I was still getting soot on the case mouth, but the extraction definitely got more difficult as the morning went on.  I've shot this load for a couple of years too with no trouble.

I brought the gun home and cleaned the chamber, checked the length of the case and it's definitely not too long for the chamber.  No rings in the chamber or brass.  Even after that, this particular case is sticky.  I've had this case a long time, no idea how many shots are on it. 

Am I pushing this too hard or should I just resize the case, flare the mouth and carry on?

Chris.

I'm no breech seating expert, but pretty sure the case needs resized eventually.

I am fairly new to this, but I am finding that certain cases need their base resized, some more often than others. I find my 28-35 needs it fairly often, so I borrowed a die that resizes the base only

gunlaker wrote Today at 4:07pm:


If it’s the case, the problem is likely at the base. Another indicator that the case head is expanded would be if the primer pocket is starting to feel loose.

It also could have been a single high pressure load. They don’t get any smaller by firing them more.

Chris. 
My main 32-40 has had no real issues with hard extraction but several of my other rifles have. I just size the case and call it good. Last session the 3 32-40 cases for the main rifle all had blowback issues with collapsed mouths on 2 and a long dent on the third. They had naan fired only several hundred times. I tossed them and used a couple of more with only 59 or so shots.

My rifle stopped shooting well a while back until I upped the velocity to about 1480 using Accurate 4100. I think that had increased blow back. I have a case mouth explosion tool if I keep having collapsed case mouths. 

Good luck