Velocity vs barrel length

[bigbadjim]

I have a 270 and shoot Hornady factory rounds currently out of Remington 700 with 22" barrel. Stated velocity is 3060 fps with 24" barrel, how much slower do you think my gun shoots with 22" barrel. I don't have access to a chronograph yet.

[speyrjb]

You lose roughly 50fps for every 2 inches of barrel length.

[stubblejumper]

Stated velocity is 3060 fps with 24" barrel, how much slower do you think my gun shoots with 22" barrel.

Velocity varies with chamber dimensions and barrel dimensions as well as with barrel length.You should be somewhere between 2900fps,and 3000fps,but without a chronograph,you are only guessing.

[HighDesertWolf]

I honestly wouldnt even worry about it, I gave up reloading for velocity along time ago mainly because top velocities and accuracy arent in the same load. Even if the velocity loss was 200 fps it wouldnt matter because a deers rib cages doesnt have a chronograph in it and wether a projectile goes through their guts at 3,000 fps or 2,800 fps second doesnt matter. either velocity the deer is gonna die.

[stubblejumper]

honestly wouldnt even worry about it, I gave up reloading for velocity along time ago mainly because top velocities and accuracy arent in the same load.

That depends on the rifle.Some rifles shoot most accurately with maximum loads,and some shoot most accurately when downloaded.

[kelbro]

The Lyman reloading manual did a chronograph test of factory ammo vs. the manufacturers claims. The .270s averaged around 150-200 fps less with 22" barrels.

[SJAdventures]

ORIGINAL: HighDesertWolf

I gave up reloading for velocity along time ago mainly because top velocities and accuracy arent in the same load.

I am quickly realizing this. I have been testing different hand loads in a new rifle and none of the upper end loads shoot as well as the middle loads do out of this rifle anyways.

[eldeguello]

ORIGINAL: stubblejumper

Velocity varies with chamber dimensions and barrel dimensions as well as with barrel length.You should be somewhere between 2900fps,and 3000fps,but without a chronograph,you are only guessing.

Stubblejumper is essentially correct. As a rule, with a cartridge with the expansion ratio of the .270, we say you can expect to lose bertween 25-30 FPS per inch that you chop off. A magnum case like the 7mm Rem Mag the loss goes up to the vicinity of 50 FPS/inch.

HOWEVER: All rifles don't lose the same amount, and in some cases, people have reported a GAIN in chronographed velocity after shortening a barrel! Bottom line: Stubblejumper said "chronograph it." That is the only way you'll ever know about your specific rifle.

I once owned two Mannlicher-Schoenauer .270 carbines. I used the 130 and 150-grain Nosler Partition bullets in them, with 55.5 and 53.5 grains of IMR 4350 respectively. The 130-grain load chronographed 2880 FPS, and the 150 made 2820 FPS from both guns. Both had 20" barrels with 1/9" twist. Both shot into 1.25 MOA, and were very deadly little rifles. I would not feel handicapped having to use a .270 anywhere in North America, nor for non-dangerous game in Africa.

[eldeguello]

ORIGINAL: stubblejumper

That depends on the rifle.Some rifles shoot most accurately with maximum loads,and some shoot most accurately when downloaded.

100% correct!