Inertial Bullet Pullers (sometimes called Impact Bullet Pullers) are used to disassmble the bullet from a cartridge without firing the round.
See photo below. This is one from Frankford Arsenal. Lyman and RCBS also make them.
The round is hed in by the collets (the 3-piece aluminum "jaws"), which is placed in the opening of the cylinder (see the threads on the "head" of the puller?) The endcap is tightened down, securely holding the round with the bullet facing the blunt end of the puller.
Hold it like a hammer, with the blunt end facing down, and bang really hard a couple of times on wood (been using it for years, have not broken the plastic yet), until the bullet pops out. Gunpowder will spill out and be captured by the end of the "head", casing with (live) primer will remain in the collet which is still securely held by the screw-in cap.
The gunpowder may be tossed into the garden, makes a good nitrocellulose-based fertilizer. The casing with live primer can be reloaded later, or the case can be fed into a gun and the primer fired (in your garage or at the range)....flaming fragments fly out the barrel when you do this, so do not aim at people, pets, your flatscreen TV or anything other than a "safe direction"...it is loud, but does not sound like a gunshot, more like a 4x4 wood plank dropped on concrete. I do this all the time in the garage and nobody has called the police to report a gunshot....yet.
*NOTE* Photo is not mine, grabbed it from the Internet.
*NOTE2* I would strongly recommend NOT pulling the bullets this way on live rounds with a misfired primer (primer has an impact on it but didn't fire), they can be very unstable and may actually fire while you are banging the bullet puller. I've heard of it happening, but have not experienced it. If you must do it on a misfired primer, first soak the base of the round (the primer) in WD40 overnight to contaminate the primer compound, and do this process while the primer is still wet, and BE VERY, VERY CAREFUL!!!!