There are currently 5 .357 magnums onwned by members of my family. Dad and I co-own a Ruger GP100, a Magnum Research Desert Eagle, and a Ruger Vaquero (on both permits). My uncle has a Dan Wesson model 15.2, and my grandfather has his old sevice pistol that he carried for 22 years as a NYS Trooper, a Colt Python. The only one that has never fired .38 Special is the eagle. Dad and I are not sure if it would cycle.
When Grandad bought his python in the '50s, NY had just phased out the .45 revolvers, and gone to .38s. He bought the pistol because of the fact that it would fire both rounds, meaning he would still be able to use it to qualify at the range, and the state would pay for the ammo. While on patrol he would carry it loaded with the magnums for the extra stopping power (an encounter with a perp on speed changed his mind as to the stopping power of the .38 special). He has fired countless .38 and .357 rounds through it ovr the years. The only advice he gave the next 2 generations regarding firing .38 in a .357, Make sure you give it a good thorough cleaning afterwards. Especially the cylender. We all have follwed his advice, and half of the rounds for these pistols is .38 Special. I dont think any one of us could give an acurate round count for any of them. I know for a fact that I can't count that high.
OP. I would go for the .357. That way you can work your way up to magnum loads, or stay with the .38s. The . 357 will give you more options when it comes to loads. Just my 0.02, YMMV.
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