There are three things at work here, when you talk about crimping.
In revolvers, the bullet(s) moving forward under recoil (jumping crimp).
2nd thing is proper combustion of slow burning powders
3rd thing is the continual contention about crimps affecting accuracy.
In handguns, #3 doesn't seem to be a significant issue.
#2 is a significant issue, and
#1 can be a vital issue.
Bullets jumping crimp varies with the guns and loads, but seems to show up as an issue when bullets get over 200gr and velocities start approaching 1000fps.
Bunny phart loads don't do it. Smaller calibers don't do it, until/unless you get up to high velocities. I've shot standard level .38 Special (158gr@850fps) uncrimped, never had an issue with the bullets moving. However, .45 Colt, uncrimped, at anything above original black powder speeds (and sometimes even then,) WILL start to have the bullets move forward under recoil.
Exactly where the magic number combination of bullet weight and velocity is, for your .44 Mag, I don't know. But I do know that there IS a point where uncrimped bullets will move forward, and if they move enough, will jam your gun.
I crimp all my handgun ammo, all calibers, all loads, light or heavy, taper or roll crimp as appropriate. I do it for two reasons. One, some loads do need it, and done right, has no effect on loads that don't need it.
And, two, I'm lazy, and I don't want to adjust my dies, which are set to give the proper crimp, and left there....
I have single shots for many of my handgun calibers, and while I don't need to crimp for them, I don't bother to make uncrimped ammo just for them. They shoot real fine with the ammo that is crimped for everything else.
Now, when it comes to rifle rounds, I don't crimp for single shot rifles. I do crimp for magazine fed rifles with heavy recoil (.458Win mag, etc). I crimp ammo used in autoloaders, and in lever guns, but don't crimp the same rounds for use in a bolt action.
You want an answer about whether or not to crimp your .44s? Load up 6 uncrimped, and shoot 5. Look at that last round. Measure it. If the bullet has moved at all, you should crimp. If not, you're fine the way you are.
Just be sure to do this test with EACH load. Just going to a different batch of brass might be enough to make a formerly satisfactory uncrimped load suffer from bullet movement. I crimp, and I sleep pretty well over it, and have, for the past 45+ years...
