Actually, if you are not going to seat the bullet "properly" (ie, just off the lands in your chamber) then, for reliable accuracy, the bullet should be crimped. Seating the bullet by neck tension only can cause inaccuracies since all cases may not have the same tension. Seating the bullets just off the lands eliminates pressure jump and evens out the pressure curve when the round is fired. If you choose not to do that then you should crimp to achieve the same result.
The mechanics of the cartridge, once the trigger is pulled, goes something like this:
Primer ignites the powder, expanding gases increase pressure and the bullet begins to be forced out. If not crimped in place, the bullet "jumps" the distance until something stops it. In that case, it would be the lands. This causes a drop in the pressure curve followed by a spike as it comes to a stop and starts to build again. Seating your bullet out until it is just short of the lands eliminates this jump.
Bullet manufacturers can't do this so they crimp. That allows the pressure to build uniformly until the bullet "lets off" and exits the case. They crimp and so do I. But not everyone does, so it is up to you. Find the method that works for you and carry on. Good luck.
Me thinks you read too much!
Many years ago, I used to teach people to fly airplanes. I will always remember when I was taking the training to become an instructor what they drilled into us.
They said don't tell a student anything that you can not demosnstrate to him/her.
You said seating a bullet well off the lands and not crimping it, would cause inaccuracies. Let's see you prove that to us.
You stated that if the bullet is seated off the lands, it starts to move as the powder is ignited, then stops when it hits the lands, pressure goes down, then pressure spikes as it starts o move again. I wouldn't ask you to prove this, but let's just use common sense. The primer fires, powder starts to burn, very rapidly and builds up pressure extremely fast. As a matter of fact, with bottle neck cartridges, the bullet has reached the speed of sound, by the time it has progressed 1½ to 2 inches down the barrel. Did you take your reading so serious that you actually thought the bullet stopped as it met some resistance from the lands, then started up again, as more pressure built?
The earlier British firearm experimenters were very meticulous about proving things. I had an old military book on experiments with the 303 cartridge. They thought that when the primer went off, pressure was so violent that the jacketed military bullet expanded to fit the barrel. To prove it they cut the barrel of a rifle off so short, that with the cartridge loaded in the chamber, the front part of the bullet stuck out of the cut off barrel. When they measured the fired bullet, they discovered the front portion that stuck out was indeed, of larger diameter than it originally was.
Does this sound like the bullet would stop when it hit the resistance of the lands?
