Author Topic: 24" or 26" barrel? (Read 933 times)

AlanF · « **on:** June 11, 2006, 12:28:30 AM »

What do you think guys? Having an E.A.Brown 97D rifle built in 256 Win Mag and I am leaning towards a 26" barrel to get every fps possible from the case. Is this too long and would a 24" barrel get top velocity from this case? Going with a 12 twist. Need advice. Thanks.

Alan

nomosendero · « **Reply #1 on:** June 11, 2006, 05:37:29 AM »

I promote long barrels quite often, but I do so for a reason & that reason being to increase velocity. But I cannot imagine such a tiny case needing such a barrel, in fact I don't even understand a 24" with this case but that is up to you. Consider the fact that you are not likely to use more than 19 Grains of powder, my manuals maxed out at 18 Grains & this is with a .257 bore!!! A .223 will show a small gain with a 26" barrel, the 24" gets the most out the round & this is with a 22 cal & 24-27 grains of powder, the combination of these 2 factors is huge & show an apples to oranges comparison of these 2 rounds.

I would think that anything over 18" is going to show a small gain & after
22" would be a joke, unless you want a front heavy feel.

Have you talked to E A Brown about this, they should be able to provide
some insight.

Don Fischer · « **Reply #2 on:** June 11, 2006, 06:03:53 PM »

It's not only going to use about 19grs powder, it's gonna be fairly fast powder. I'm not crazy about 18" barrels but I'd think a 20" would be right there. 22" might give you a bit more velocity but just how much more is the question. Nomosendero, have you ever found out how much extra velocity you get from a 26" barrel as opposed to a 24" with say your 25-06? I've read different things and there lots of differences. Years ago Jon Sundra took a military rifle and cronographed loads out of it. After each session he cut one inch off the barrel. I don't recall his results but they were less than we were led to believe back then.

Alan F, What are you gonna use a 256 for anyway?

nomosendero · « **Reply #3 on:** June 12, 2006, 02:13:35 AM »

Seems like Sundra used a 30-06, but as you say it was a long time ago.
Rem. likes to be lazy & say it will be about 25FPS per inch & it is for some rounds like a 223 after 20" or a 308 again after 20" or so. Rounds like the
30-06 are close to this but not quite. On the other hand a round like the
subject of this post would gain almost nothing per inch beyond 18" whereas the 7mmSTW or even moreso the 7RUM would see huge gains up to at least 28".

The 25-06 is a Horse of a different color for a 30-06 case cap. round with
it's small 25 bore. I have no desire getting into an argument with someone who is getting good velocities with a 22" barrel (can happen with a fast barrel), but this round really needs at least a 24" tube & is best with
a 26" barrel. I have worked with several 24 & 26" barrels & I will never again buy a 24". I have seen 100-150FPS difference which is worthwhile
to me & with my current AI version with heavy bullets & slow powders
loaded to max. SAFE pressures, 175FPS is likely to me, but I could only
be sure by cutting my barrel & checking which I will not do.

Again, to anyone who reads this & thinks the 24 will be right in their, fine
& dandy. But Don this is what I have experienced & I have done about
all I can do with this round & am ready to start working on another round
or 2 this year.

Don Fischer · « **Reply #4 on:** June 12, 2006, 05:26:24 AM »

Your probally right about the 30-06 and Sundra. I think your right about the rest too. I've heard everything from 25fps to 75fps also. Whats to believe? But I'm certain that case capacity plays a major role in the effect of lenght of barrel and muzzle velocity.

I have a theory on barrel lenghts. 308 size cases do well with 20 to 24" barrels and 30-06 cases do well with 22 to 26" barrels. Longer than 26" becomes ungainly to handle in a hunting rifle. For the 25-06, 6.5-06, 6.5-284, 270 and 280, 24" is as short as I'd go. Back up a bit, because of bore dia, I think that a 243 with a 20" barrel would be a night mare. A 243 should have at least a 22" barrel and 24" better.

Mac11700 · « **Reply #5 on:** July 21, 2006, 05:08:43 PM »

Try a nice single Handi-rifle with a 26" or longer barrel...they really make a difference if you want a longer barrel...even the 28" Thompsons are easier to get thru the thickets..and thse single shots balance quite nicely too..