BREECH SEATING NOTES

On Breech Seating               There is at least a hint that something happens during the leap of the bullet from the case neck to the chamber that reduces accuracy. Breech seating the bullet is suggested as a method of eliminating the leap and accuracy reduction. It has been noted that the .22 rimfire can exhibit supurb accuracy, and that the heeled groove sized + bullet is sort of breech seated.             Years ago we loaded rifles from the muzzle and were able to shoot very accurately. The introduction of the breech loader speeded up the shooting and reduced the fouling problem, but didn't do much for accuracy. A succession of gunsmiths and shooters, typified by Harry Pope, worked on the accuracy problem, and arrived at three solutions.             First and most succesfull was the jacketed bullet, which seems unaffected by the leap.             Next was the breech-muzzle loading method, where the bullet was pushed through a false muzzle and down the bore to a certain location; after which the loaded cartridge case was put in the chamber and the gun fired. This worked, produced great accuracy, but had enough problems that the method eventually disappeared.             Last and still widely used today was breech seating, with the bullet pushed into the chamber end of the barrel, followed by the loaded cartridge and firing.             Breech seating involves pushing the bullet into the chamber and rifling, so there are four design elements that interact: chamber design, bullet design, bullet hardness and breech seating tool mechanical advantage.             A chamber designed around the bullet reduces breech seating effort.             A bullet designed around the chamber reduces breech seating effort.             Harder bullets are harder to breech seat.             Many breech seaters are simple pushers, yet some breech seaters have enough mechanical advantage to seat a steel bullet.               Chambers vary from SAAMI to precisely throated  designs for a specific bullet.             Bullets were, for a century or more, flat nosed multi band= multi groove tapered base-band Pope style. Pointed noses were known to cause inaccuracy. More recently some brave shooters have adopted bullets with pointy noses and fewer bands, and are shooting accurately.             Single shot guys, breech seaters, tend to the belief that only tin and lead are correct bullet metals, and delight in talking about the relative merits of 20 to 1 vs. 30 to 1 vs. 23.6 to one alloys. They keep well away from harder alloys, because the force required to breech seat increases fast as bullet hardness increases.             Most single shot guys breech seat with a simple pusher, sometimes seating with a plugged case and an Stevens 44.5 or Ballard action or another action exert force on the plugged case to seat the bullet. He use of involved levering breech seaters is, at least in my experience, less often seen.               Chambers can be designed around certain bullets, rifle chambers can be throated, but I prefer to use guns with production chambers. Better accuracy may require more machine time, but very good results can be achieved with modern production chambers.             Bullets can be and have been designed for breech seating, by accident. Some old designs work fine breech seated. The 311299, 314299 and 31141, properly sized, can be breech seated in about any .30 caliber rifle. This is simple, the nose should engrave and the band should seal the bore. With the band sized for the rifle's chamber, it does a fine job of sealing the bore and the combination of the band end and nose align the bullet. The trick here is that the bullet DOES NOT have to go in the chamber so the base is ahead of the case mouth-the case mouth can go around the bullet base.               While the mathematical relationship between bullet hardness, chamber pressure and accuracy, what I call the “Davis/Harris/Lee myth”, has been solidly disproved; there is the fact that harder bullets shoot better fast than do softer bullets.               Soft bullets are thought to be needed to breech seat, limiting velocity to somewhere around 1500 fps. But, we don't need to use soft bullets to breech seat, we need correctly designed bullets seated as far BACK as just gets the band to seal the bore.  Could we breech seat linotype bullets and shoot them fast?             We don't need a Rube Goldberg seater, the bullet can be pushed into the chamber with a plugged open mouthed case that sticks it into the chamber. An hour and even I can make one.             Or, a clever machinist could make a case with a solid inside step at the appropriate location, and that would allow “fixed breech seating.”