130 guns, 20,000 rounds of ammo found in foreclosed CT home

[overthehillvet]

144. Nope still not quite right

After a certain length as determined by the point where the gasses stop expanding the bullet will not continue to be accelerated.
First we are talking about firearms here and not tools.
Second, I've built about a 50 rifles, have been reloading for 45 years, and compete in long range bench rest competition at least once a month. I do know how a rifle works.
I can take any rifle and trim the barrels an inch at a time and demonstrate with a chronograph that they loose velocity with every snip. This is not rocket science. These things are very well known and understood by those who build and repair firearms.
The difference in the velocity of a .284" or 7MM diameter SPBT, (spire point boat tail) bullet that weighs 150 grains coming out of a 20" barrel and a 22" barrel is about 100-150FPS depending on the case capacity, case contour, and powder amount/density/type, and then temp and humidity. Yes that is an increase in measured muzzle velocity out of the longer barrel. The ratio of increase will stay pretty constant until it reaches somewhere around 27"-28" and reaches the point of diminished return.
I'm not sure exactly what point you are trying to make but I know exactly what I'm talking about.