The Colt Single Action Army Barrels & etc. By Dennis L. Schrieber, Pistolsmith
For many years now the Colt Single Action Army has been primarily a collectors firearm. Colt still puts a letter in the box with each gun, informing the proud owner that if they fire the gun that it will lose its value.This philosophy may explain why a pistol that is this much fun to shoot can have as many problems as they do. Todays growing popularity of Cowboy Action Shooting has changed the way we look at the SAA. Im sure that a lot of collectors would shutter at the sight of a 1st or 2nd generation Colt being fired from holster at the local SASS event. The philosophy is being shot full of holes. Historic items aside, these firearms are made to be used, shot and enjoyed.
A lot of the cowboy shooters are using one of the many SAA clones. However, the problems encountered are not limited to these Italian imports. The foremost problem that is encountered, across the board, is the lack of a proper forcing cone, and a proper cylinder to barrel gap. In just about all the pistols, the forcing cones are roughly formed and generally not square to the bore. A properly cut forcing cone is essential to accuracy and to reducing lead build up in the bore. In most examples, the forcing cones are found to be non-concentric with the bore, very rough, and not cut at the right angle. The bullet upon leaving the charge hole, in the cylinder, will not be correctly guided into the barrel. Bullet distortion and unwanted vibrations will occur. If the cone is not polished smooth lead will build up fast. As the lead builds it causes shot to shot variations and is not conducive to good groups.The most common problem found with the cylinder gap is really not what you would expect. The gap is generally within tolerance but usually not cut square to the bore. This also causes the bullets to enter the bore, upset.Also, in this area of the firearm, the other problem encountered is the lack of lead into the rifling. This, I believe, is all proof that the forcing cones are formed when the barrels are made and not cut during assemble.
The angle to which the forcing cone is cut and the size of the cylinder gap can be a point of many debates.Different manufactures have promoted the merits of different angles on different firearms over the years. We can find 5, 11 and 18 degrees among the most common.Ruger has touted the merits of the 5 degree while 18 degrees is the most popular. 11 degrees is generally considered to be gentler on the bullet and causing it less distortion. After the cone has been cut and polished to the right depth and the end of the barrel cut square to the cylinder, I recommend just breaking the edge of the cone with an 82 deg. cutter.
Cylinder gap can easily be increased using the same, bore guided, tool set that is used to cut the forcing cone.To decrease the gap requires that the barrel be set back. To set back a barrel, it is removed from the frame, mounted in a lathe, and the face is turned just enough to allow the barrel to be screwed in one full turn. After remounting in the frame, it can then be refaced to the desired gap. Some shooters want a very tight gap. The theory being that the smaller the gap the less gas will be lost thus, greater efficiency.Other shooters will point to the many test that have been printed that show little or no change in velocity or muzzle energy as the gap is increased. But, thats a debate for a different time.Just remember that smaller gap also means that the bullet has less space to jump and therefore less chance to become misalign with the bore. However, this also means, that the gun will become more sensitive to heat and dirt. A gap of .006 inches is generally excepted as average and desirable for most shooting sports.The SAA design has been with us for about 160 years. What a great credential! So, if you love these handguns and like to shoot a classic design, then tune them up for maximum enjoyment.Remember to keep the sport fun and safe and visit you favorite pistolsmith. Please direct comments and questions to Dennis L. Schrieber, Pistolsmith at: email firstname.lastname@example.org or www.burntmill.com.