by rc42 » 06 Aug 2021, 10:06 am
AP50N is a pistol powder but is essentially the same as AS50N shotgun powder except that it is cut into smaller, rounder flakes/particles to make smaller weight throws easier. In general, they can be both be used interchangeably but at the same weights rather than the same volumes.
Having said that, AS50N is 'Not Recommended' for 410 use according to the 2000 ADI load data and it is a significantly faster powder than 2205 so it would be much easier to create a dangerous pressure spike. Any powder will explode and work but without access to safe load data your options are don't use it or work up your own loads slowly.
Given the slower nature of 2205 the Trailboss might be a better idea, especially as it has such a low density that it's near impossible to overload using it. If you work up to a full load of Trailboss and it still isn't enough you could try small amounts of AP50N in the case first and top up with Trailboss. Clearly the warnings are DON'T ever mix powders but that's the manufacturer's disclaimer that their lawyers make them put out, the reality is that you can mix anything as long as you work up loads slowly. You could also look at using a slower rifle powder (which are still available) and use a tiny amount of AP50N to increase the burn rate if it's too slow.
Here's my disclaimer - get it right and you will have shooting fun but get it wrong and you may have to live without some important body parts, stay safe and work up any loads slowly.