Barrel lenght

I guess i kinda left that wide open. Ill try again. I am building one nice 600 yard rifle for the shoots in St Louis this coming year. I am going to go with a 6BR or a dasher. Haven't decided. My Barrel will be big and heavy, so i want to keep it as short as possible without sacrificing any speed. What would you fellas recommend? Is 26" to short? Also isn't it true that a shorter barrel will have less whip when fired? Thanks Lee
 
skeetlee

yes there will be less flex or whip with a shorter and or fatter barrel. the bullet is pretty much up to speed at 24 inches ,after that you will loose about 8-10 fps per inch .the larger loss would apply at 24 to 16 inches area of the barrel.hope this helps sir. tim in tx
 
tim

Hmmmmm.:cool: That's bound to start a few lively posts.

Ray
 
well it is winter ray

here is a quickload calculation of a 6br norma. the second is for a very long barrel .the quickload predicts an aver. of 17 fps loss per inch between 25 and
30 inches for tis particular combo.tim in tx
 

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skeetlee said:
My Barrel will be big and heavy, so i want to keep it as short as possible without sacrificing any speed.
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The word "any" means the same as "no loss" in this usage. You will always gain speed with a longer barrel, at least, until you get to the point where the pressure in the barrel is less than the loss due to friction. That is probably well over 30 inches in a 6BR. Jackie Schmidt did some testing for 6mmBR.com. Read that.
 
tim in tx said:
yes there will be less flex or whip with a shorter and or fatter barrel. the bullet is pretty much up to speed at 24 inches ,after that you will loose about 8-10 fps per inch .the larger loss would apply at 24 to 16 inches area of the barrel.hope this helps sir. tim in tx
Click to expand...

This is a fine answer, very concise IMO.

Good On Ya Tim :)

al
 
george sir

i see it a bit differently. i see at 25 inches the gains are very small from that point on out ,so why grind on the bullet more?i think it is possible in some cases the shorter barrel can be better then a long barrel just because there is less wear and heating on the bullet jacket which could be of help to accuracy and all bullets arriving to the target safe and sound .and do realize these are just calculations,but in real life the gains i have seen in the 28to 27 inch area were very very little per inch averaged over many shots fired. it may not jive with other peoples rifles but i do agree there are many varibles as you spoke of.it sure would be a lot easier to say if i had 0 velocity variance but that darn sure won't happen,but with many shots averaged together over time in controled conditons with 6 dasher 8-10 fps is my best guess with 6 fps extreme spread on a chrono with 9ft spacing. tim in tx
 
Skeet,

6 Dashers and BRs in particular are pretty easy on bullets compared to some other chamberings. We don't see much evidence that long 6BR barrels tax the integrity of bullets so there isn't much downside to a long-ish barrel. If you expect to shoot a lot a 30" will give you the opportunity for several set-backs that you won't have with a short(er) barrel and you can shoot more for the same money...always a good thing.

Greg
 
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Lee,

I don't pay to get more length. I tell the gunsmith to leave the barrel as long can he can. I would go with the Dasher or a 6BRX.

Mark Schronce
 
Here is my deal. I should have mentioned this before. I have a new Krieger 6mm 8twist 1.250 straight barrel. It is heavy! I dont want to go to short with it but i dont want to go any longer than really needed either. Thanks Lee
 
Skeetlee, your not clear as to your goal, if you want to maintain maximum velocity you need to keep the barrel as long as possible, if you need to make weight you can keep your barrel at 28 inches and flute the barrel to lose the extra ounces, This should be done as part of a planned rifle so you know what you need to do before you start work.
Leroy Johnson
 
Leroy
This will be a prairie dog/ f-class rifle. I have 22 pounds to work with so i wasnt real worried that i would be over weight. I am a little concerned as to how the rifle may ride the bags if it is to nose heavy. Thanks Lee
 
From what i have observed at matches and from what i have built. Seems to be short end 28" on a new build . As was said earlier as a builder and a shooter I want more 30 " .Then when the time arrives, you can set back and rechamber and still have good lenght for velosity and balance . From a proformance point that is the length i recommend . To address your nose heavy concerns barrel fluting and counter weight in the butt of the rilfe will balance it out . www.therifler.com
 
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Lee,

With a BR based cartridge, you have different folks using it for various compeitions.

If benchrest at 600 yds, then I would look at 27-28 inches with 4-5 inches of untapered breech end. That way I can set the bbl back once or twice to maintain a good throat.

You can shoot a 30 inch bbl and have more velocity if you ever plan to shoot longer ranges (1K).

Bbl life is very good with this cartridge so that should not be an issue.

I have a BRX and shoot both 600 and 1K prone. The BRX is my choice because I didn't want to have to purchase expensive custom dies. Standard BR dies along with a 308 body die (which I already had) can load the BRX easily. The Dasher (an equally superb cartridge) takes custom dies. Both have identical performance on target.

Pay your money and take your choice.

Bob
 
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