Before I bought my 38-55 Marlin CB, I read everything that was on the various forum sites. In spite of what I read, I went ahead and got one, the dealer throwing in one box of WW factory loads. Since I had no dies, moulds, brass to start loading, I first tried the WW ammo, undersize that it supposedly is. With a receiver sight installed, that factory stuff shot very tight at 50 yds. And recoil with these loads was very mild. I now had high hopes for my 38-55.
Slugging the barrel told me it was .379 and when I began to cast for it, I sized at .379 and that works fine in my barrel with two different bullets, a Lee 250 and a Ripine 260 GC, which I shoot at silhouettes.
With deer season approaching, I thought of trying the 38-55. I sighted it dead on at 100 yds. with the factory load. Final sight adjustments before the season were complete and my son, unfortunately brought up with scoped rifles, tried one shot with this peep-sighted Marlin. His shot, fired on my target, hit within 1 1/2" of mine! He was surprised but gained some respect for open sights that day.
With 5 remaining cartridges from the original box, I killed a doe of about 100 pounds that year. Excellent bullet performance, a good blood trail and a short track job to the deer. Now I have 4 left and "one of these days" I'm going to chronograph them.
I now have over 2000 rounds through this barrel, most at silhouettes, some at targets, and except for 16 factory jacketed all have been cast bullets. But, everyone that shoots these allegedly undersize Winchester factory loads tells of their accuracy. I just don't believe I have enough financial resources to shoot 2000 factory loads in about three years.