I was exploring my world and Surprise!, the loot of the minecart was dispersed around them, i checked inside and the dispersed loot was the same at the inside loot, this never occurred.

I tried to see what is happening,I removed mods, config and reseted my game, and i found the problem, the bug is in the ultimate version (after the beta 5) of railcraft.

(If my english is bad, is because i don't speak english).

For future reference, a simple

((EntityMinecartContainer) entity).setDropItemsWhenDead(false);

before calling setDead() here should fix this. EntityMinecartContainer#setDead() drops all its contents on the ground unless that flag is false.

So since loot spills around the minecart, is there still any loot left in the minecart

Yes, the same items are still in the minecart.

Yep just ran into this, issue still happening

Use the latest beta. Unfortunately, this error appeared in the release version.

Fix should be easy, but unfortunately I don't think a version will be published recently

Have tried to modify the mineshaft loot for hours, and no matter what loot still gets dispersed.

@Tolans I am using the latest version posted here, where is there a later beta?

https://www.curseforge.com/minecraft/mc-mods/tidychunk
Could be a possible workaround ^
Because this is annoying:

Have tried to modify the mineshaft loot for hours, and no matter what loot still gets dispersed.

@Tolans I am using the latest version posted here, where is there a later beta?

https://www.curseforge.com/minecraft/mc-mods/railcraft/files/2672397

Is that build newer than Railcraft 12.0.0? It was uploaded a month earlier... it doesn't make much sense

Have tried to modify the mineshaft loot for hours, and no matter what loot still gets dispersed.

@Tolans I am using the latest version posted here, where is there a later beta?

https://www.curseforge.com/minecraft/mc-mods/railcraft/files/2672397

Is that build newer than Railcraft 12.0.0? It was uploaded a month earlier... it doesn't make much sense

This is no newer than the release version, of course. But it just makes sense, because the error with the loot appeared in the release version. She wasn’t in beta.
See the log of changes in the release version. Almost nothing has changed there, so you don’t lose anything using the latest beta version.

Have tried to modify the mineshaft loot for hours, and no matter what loot still gets dispersed.

@Tolans I am using the latest version posted here, where is there a later beta?

https://www.curseforge.com/minecraft/mc-mods/railcraft/files/2672397

Pains me that this issue still isn’t fixed,

I can confirm that I have seen this myself. If I had to guess, I'd wonder if has to do with the carts being replaced with Railcraft versions?

This probably causes some server lag to be sure, however there is no loss of loot. For whatever reason, in abandoned mineshafts, it duplicates the loot outside as is inside. I was concerned at first until I checked it out. Picked up both and it was same items and same quantities.

I haven't observed this occurring in any other places in the game (or in other modded areas with loot).