I recently acquired an 3E, 1906 mfg with HOT and ejectors. All worked perfectly using snap caps.

The problem is when opening the breach after shooting the first time, it takes considerable force to open. Once open the shells eject as expected and the breach closes easily with no looseness or gaps between bbl and receiver.
I shot 10 rounds with same results. HOT a bbl selector worked as normal as did the ejectors.
After shooting session, it works perfectly with snap caps.
Any thoughts are appreciated.