George,
The "secret" to getting .38 Spl to work in some 1894's is to seat the bullet out a bit further. I have never had an issue with either of my Marlins running 1.54 COL.
They had to run fast to be competitive in CAS. I could get off 10 shots in 5-6 seconds. The really good guys were about 3 seconds. This with "tuned" 1894's.
Edited to add:
I was getting ten shot 1" groups at 30 yards with "mouse phart" loads. I need to see how the gun shoots at longer range with .38+P loads once the weather gets better. Surprised the gun reviewed did not do better. I would not be a happy with 3" groups at 50 yards from a $1000 gun.