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Brennan19
July 3, 2012, 02:47 PM
I am currently building a custom 98 Mauser and was wondering what length should I cut my barrel off for the best results. I have 26' chrome moly Shilen in 308 with a 1&10. Also it is #7 Winchester contour. I plan on shooting distances out to around 600yds. Any advice helps thanks.

Brian Pfleuger
July 3, 2012, 03:04 PM
It is generally accepted that barrel length, in and of itself, is not relevent to accuracy.

However, a little reading of Secrets of the Houston Warehouse (http://www.angelfire.com/ma3/max357/houston.html) and you'll see that they found 21 3/4 to be the most accurate length.

The caveat being that those shooters would consider 1/4" 100 yard groups to be horrendously bad, completely unacceptable, while many "normal" folks may never, one time, shoot a 1/4" group and most guns are completely incapable of it.

In terms of velocity, there are diminishing returns beyond a certain length, impossible to say exactly without at least running the calculations through QuickLoad. Suffice it to say that somewhere around 24" is about normal and even that is well into diminishing returns.

I'm in the earliest stages of building a deer rifle and my barrel will be 21 3/4 because, well, it can't hurt and it might help. I'm giving up little velocity but a fair amount of weight by dropping from 26 or even 24 inches.

As always, your opinions and mileage may vary.

k4swb
July 3, 2012, 03:26 PM
I had a Weatherby Vanguard with a 24" bbl.With my hand loads velocity was in the 30-06 range, 3000fps+. It was awkward to me so I cut it to 20" and lost a slight amount of velocity, down to 2800fps+.

The deer didn't know but it handled much better.

Brennan19
July 3, 2012, 03:30 PM
Thank you for your input. I will take a look at the "Secrets of the Houston" warehouse. Maybe I can pick up a little extra knowledge for myself.

Brennan19
July 3, 2012, 04:28 PM
Maybe I should clarify my intentions for the rifle I live in (IN) rifles are not allowed here for deer hunting :( what I'm trying to make is a decent target rifle without breaking the bank. That is why i when with the Mauser action , but i would still like it to be useable in the field so it does need to handle decent. which means going with a shorter length so i thank you for your input

old roper
July 3, 2012, 04:34 PM
here something on a 308

http://www.6mmbr.com/gunweek100.html


http://www.6mmbr.com/gunweek097.html

Brennan19
July 3, 2012, 04:52 PM
I'm leaning towards 23 1/2 to keep the weight up. i think that would be a sort of "happy medium" between maintaining velocity and the ability to handle it in the field.

Bart B.
July 3, 2012, 05:31 PM
Your 26 inch one will probably prove best for longer ranges. That's the length that was common for high power match rifles when the .308 Win. was "the" cartridge to use. It keeps bullets from 168 to 220 grains fast enough to remain supersonic through 1000 yards. And its 1:10 twist is perfect for 190's, 200's and 220's.

Note that those Houston warehouse secrets were for only one benchrest cartridge and barrel taper. And Winchester 70's with 26 inch barrels in .308 Win. have shot some of the smallest groups imaginable at 600 yards; some better than most current benchrest records.

Brennan19
July 3, 2012, 05:58 PM
I planed to shoot the heavier grain bullets so i did do my home work as far as the rate of twist which as you said 1&10 is perfect for 168gr up to 220's. forgive me if i sound "newbish" or "uninformed" but i was thinking that a 26" barrel was too much barrel for a 308. By too much i mean that it gets to the point where there is no benefit of the extra 2 or 3 inches.

jmr40
July 3, 2012, 07:05 PM
Anywhere between 20-22" is the best balance for me. Anything longer does not help velocity enough to matter. I've never found anything shorter than 20" to be any handier.

Jerry45
July 3, 2012, 09:50 PM
I planed to shoot the heavier grain bullets so i did do my home work as far as the rate of twist which as you said 1&10 is perfect for 168gr up to 220's. forgive me if i sound "newbish" or "uninformed" but i was thinking that a 26" barrel was too much barrel for a 308. By too much i mean that it gets to the point where there is no benefit of the extra 2 or 3 inches.

I just had this built by a Bench-rest shooting champion. At his recommendation it has a 24" barrel. The same as his. It also has 2" of muzzle brake on the end of it.

http://i237.photobucket.com/albums/ff155/germil1/Remington700Custom308RightSide1.jpg


And before anyone says anything. Yes, its built on a long action.

Brennan19
July 4, 2012, 09:49 AM
That's a good lookin piece and a damn fine scope !

Jerry45
July 4, 2012, 01:00 PM
Thank you. Now if I could shoot as good as it looks that would be something. :)

Bart B.
July 4, 2012, 03:26 PM
Brennan19 comments: forgive me if i sound "newbish" or "uninformed" but i was thinking that a 26" barrel was too much barrel for a 308. By too much i mean that it gets to the point where there is no benefit of the extra 2 or 3 inches. .308's need 30 inch barrels when they shoot the 147 to 155 grain bullets in Palma rifles. Otherwise, the bullets won't leave at 2950 fps or more to stay supersonic through 1000 yards.

I've got a 32" barrel on my Palma rifle and 155's leave at 3120 fps from .308 Win. cases. When 155's were first used in competition at 6600 feet elevation, folks with 26 inch barrels started having problems at 900 yards and often so at 1000 because they didn't shoot 'em fast enough. At lower elevations, the problems got worse.

Jim Watson
July 4, 2012, 03:44 PM
I have a 28" barrel on my .308 target rifle for mid- and longrange F class.
Why 28", you may ask?
Because that was the longest Pac Nor sold then without charging extra per inch.

Oh, by the way, the Houston Warehouse Magic Length is 21 3/4" not 21 1/2".

Brian Pfleuger
July 4, 2012, 03:58 PM
Oh, by the way, the Houston Warehouse Magic Length is 21 3/4" not 21 1/2".

Right you are. That's what trusting a faulty memory gets you. Editing original...

Brennan19
July 4, 2012, 05:33 PM
That seems to generally be my problem too I can't shoot a good as the gun will or as they look . But I geuss that's why I like shooting theres always the challenge of shooting the next shot better than the last.

Bart B.
July 4, 2012, 10:05 PM
Brennan19 says:I can't shoot a good as the gun will.Welcome to the human race. Neither can anyone else when they hold them against their shoulders to shoot them. National champions and record setters in high power match rifle disciplines have tested their .308 Win.'s clamped in machine rests. Their rifles will shoot sub 0.5 MOA all day long at 600 yards so tested without human contact except on their light trigger with an index finger. They throw parties if they can shoot them in the steadiest position, slung up in prone, into no worse than 1.5 MOA at 600 yards.

Seems us humans have got this heartbeat that keeps bouncing the rifle around, muscles that don't hold still and react the same for each shot and a body that never gets the rifle back into shooting position exactly the same way for each shot.

Brennan19
July 5, 2012, 03:56 PM
Pretty much we aren't machines we are humans and therefore we aren't perfect so if I can hit the target and be consistant I'm a happy camper