Anyone ever use max 44 spl data for 44 mag powder puff loads?

No, you're not supposed to. If you are referring to using 44 Special data in 44 Mag cases, that's not a good idea. The 44 Mag has about 13% more room inside the case than a 44 Special does. If you are using minimum charge loads with 44 Special data, but loading that in a 44 Mag, you can have dangerously low pressures. You have to increase those charges some since you are firing them in a 44 Mag case. I would not recommend using 44 Special data and loading it in a 44 Mag.

There's also something called flash over, that causes over pressure. And with the recoil pushing all the powder forward, this can also cause an issue in a pistol. There is a reason why the manuals list a min and a max. Some powders can handle reduced loads (going below minimum listed powder charges) and others can not. Big magnum rounds typically do not like to be reduced. But to each his own.

With the powders you listed, i am not sure how you would have dangerously low pressures. Worst that will happen is a stuck bullet, which could be dangerous if you are a moron, but I assume that you are not. I have loaded lighter than listed loads in rifles and pistols with titegroup and unique and still have all my fingers, toes, and guns. Experimentation is one of the best parts of reloading. Be sensible and all will be fine.


Have a good one

Danger! Light loads in big cases can blow up.

http://reloadammo.com/liteload.htm

Or here
Is Detonation Real?
There has been a lot of ink spilled about the phenomena called detonation. As I shoot I lot of reduced loads with and without a filler it has long been an interest/concern of mine. From all the info I've been able to gather over the decades the description Howlin' gave is the one most agree on. However, if pushed a little no one I've spoken with or written to has confirmed that 100%. I don't know if that matters because 100% of those I've communicated with and every experienced handloader I know agrees that with very light loads of fast burning powders there is something peculiar that goes on, sometimes with devastating results. As Pawpaw mentioned H-110 and 296 seem to be the greatest offenders if charges are reduced below recommended levels. Other faster burning powders have also been known to create the situation.

I have never, personally had any problems with any reduced load I've used nor have I ever seen an example of what is called detonation other than in pictures. The method of my personal reduced loads are well documented by proof houses and highly experienced handloaders and I don't vary from the formula. However, with certain powders there is no question that occasionally "something peculiar" happens.

As others have mentioned if a loader stays within the guidelines of published data there shouldn't be any problems. For those old or seldom seen cartridges there is powders available to day that pretty much eliminate any guesswork in building a suitable load. Trail Boss was mentioned by db and AA5744 is another.

Good thread, interesting topic.

https://www.thefirearmsforum.com/threads/is-detonation-real.174838/