Say a fellow was to build a 26" barreled 358 Winchester or 338 Federal , how much of a velocity gain would he stand to get over 22" barreled version.?




Let's say it would be slinging 200's/225's/250's.

Or

The 338 Federal running 185'/220's/210's.

Starting at 26" you'd lose about 50 FPS per inch with medium burn and mid weight projectiles.

In my experience it’s about 25 FPS/in.

For the 338 Fed, a 180/185 runs high 2700s out of a 23” barrel, 210s are 2600. Add about 75fps to that and I think you’ll be real close for a 26” tube.

There is not enough velocity loss from a shorter barrel to have to put up with a 26 inch barrel.

Fake news.

scott, that’s just kooky talk. The last few posters are right on. Why screw around with a long tube for just a minimal gain in velocity that will really gain you nothing with the chamberings you’re talking about. If you want to huck bullets at higher velocities, just get something with more engine room and stick with a shorter handier package. Just my .02

The .358 Win is a very efficient round and gain/loss per inch are going to be fairly small compared to many rounds. The thread below has some numbers (shot from 2 different rifles/barrels so that may make a little difference):

https://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/6601301/1

Answer to question: With mid speed powders and 168 grain bullets a comparison across my various 308's shows about 25 fps/inch. The 358 will likely show that or even less.

Opinion: If I didn't mind the extra weight of a 26" barrel I'd take the steel of the last 4" and use it in a heavier contour 22" barrel.

I know, was thinking of trying to get a little more heat out of a Savage 99, I've got a line on a donor and a 358 rotor in my possession.

Since there is nothing to be gained, 20" - 22" is where I guess I'll land.

Bullets from a 22” 338Fed tend to go through critters quite well. Another 75fps would be nice, but won’t them any more dead. I’ve held 26” barreled rifles that felt quite good. I wouldn’t discount the idea. Do whatever works for you. For the same weight I’d rather have a longer barrel.

Thanks prm,

That's the other thing. My 99/300 is 24" and hangs and handles well. So I was considering that if going to a slightly larger bore (.338/.358), barrel weight would be less (if same contour). Plus, when running irons, the extra radius may be advantageous.

Asking and thinking out loud...

Guess another way to gain some speed would be to run a 99C set up (magazine) for the 284 Win case...necked to 338/358. In essence a short 338-06/35 Whelen.
I'm a little quicker with follow ups when running a lever...was my thinking

I can’t imagine giving up one of the 358’s significant advantages to try to achieve what other options can do so much better.

To put this in layman's terms.

The 358 doesn't have a large powder magazine (capacity) to benefit much in 4" of additional barrel length.

Where you see the gain/loss in longer/shorter barrels is in rounds LIKE 25-06 / 270 / 06 and the magnums. The 308 suffers from the same limited powder capacity. AS your bore increases in dia. the longer barrel does NOT add a lot to vel. increase *** in small capacity cases***.

Jerry

358wsm -

The 4" extra radius will have surprisingly little effect over a 22" radius.

Assume you can align the irons so that the front sight is no more than 1/32" to the side of dead-on-target. (If you have decent sights you can probably do better.) At 100 yards that translates to the difference between 5.11" for a 22" sight radius and 4.32 for a 26" radius - a difference of only 0.79". If that distance is critical, I suggest using glass instead of irons.

The diameter of a standard clay pigeon is 108mm or 4.25". Using the ghost ring sight on my 16.1" barreled Ruger Scout .308, I can hit a clay at 100 about 80-85% of the time. I can't do that well with the irons on my 20" barreled Browning B92 in .44 Mag. The sights make a much bigger difference for me than the sight radius.

Kilk,

Ya got a way with words.!

Beautiful Moose.!

CH,

I'm picking up what you're laying down. Very well explained.

..............Keep your barrel length 20" to 22".....Although an extra 4" to 6" gains you more velocity, it really gains you nothing extra in the field where any practicality is concerned. And I'll bet that the bulk of your hunting distances using a 358 WSM won't exceed 200-250 yards anyway?? The 358 WSM imo, is a medium to a medium/long ranged cartridge at best. And imo, the shorter barrel better matches the round and will be much handier in the field as well.

Both chamberings beg for a 20”-22” snout.

.....................Also applies to the 338 Federal