Thread: Barrel Lengths and Accuracy

oh yeah...and long barrels are a right pain in the arse in the bush!!!!!!

From experience I have decided that longer thinner barrels are not necessarily less accurate but more difficult to tune. Also regardless of the dimensions nothing replaces quality/consistency of manufacture. I have had two Savage .308 target rifles with "Truck Axle" barrels, one shot fantastically and the other average. I also had a 300win mag savage hunting rifle with a long thin barrel that shot almost as good as the best of the two target rifles. That is until it had fired more than 5 rounds and groups started to open up.

Thicker barrels also tend to maintain performance after firing a few rounds, thinner barrels are more likely to distort and loose accuracy/change point of aim on heating. Once again it comes down to metallurgy and tuning of the barrel.

Originally Posted by Micky Duck

oh yeah...and long barrels are a right pain in the arse in the bush!!!!!!

Really...depends on how you hunting and what bush you in. I bushstalk all the time. Most of its in beech or native, some scrub but most places as soon s you get out of the car and hit the bush you might see sign so not travelling lighting fast. Because im always nearly holding my rifle, and not carried over the shoudler ive found the longer barrel no problem at all. My go to 243 is 22 inch and my 308 is 24 inch shooting 150sst at 2995fpss(chonry). Even the 24 inch 308 i never thought about cutting it down. If you stalking along, carrying your rifle it barely gets hung up, or will be a problem compared to a shorter model with say a thicker suppressor on the end .(yes, i have carried my mates short verison). Each to their own, but some of the bush is quite thick where i hunt and the longer barrel isnt a big issue for me.
Pig hunting is a different matter, as travelling faster a longer barrel is a pain in the arse, but if you stalking deer, you going slow, the slower the better so no problem really but thats just me

Barrel length itself makes no difference to accuracy, but long thin barrels shoot tighter groups when shortened, albeit at lower velocity. The quality of the barrel and the design of the profile are the critical factors. A good pistol barrel is potentially as accurate as a rifle (I have shot a 1.75 inch grpoup at 100 metres with an 8-3/8" S&W M29 .44 Magnum) subject to being of suitable quality. The old L1A1 SLR is usually good for about 3" groups with the standard skinny barrel, but shortened down to a couple of inches ahead of the gas block produces groups around 1" due to greater barrel stiffness. The ideal is to find a profile and length that gives an acceptable weight, reasonable barrel stiffness, and acceptable velocity for the ranges it is intended to be used at. From a hunting perspective MOA accuracy is not very important anyway. 2 -2.5 MOA is perfectly acceptable for bigger game at normal ranges (out to about 250 metres).

Thanks guys, never thought this topic would attract so much response! I feel it prudent for me to clarify something here, before well all get too carried away!

I'm talking a .300 RUM cartridge in a barrel length of 24 Vs 26"! A guy opened his yap and said that a 26" barrel would have more velocity for that particular cartridge (.300 RUM) than a 24, however, the 24" would have greater accuracy! (something that I'd never heard of before!)

I'm wanting to shoot 800 - 100 meters and was wanting to know if the shorter barrel would be more accurate (which given only 2" difference is probably completely undetectable!)

I tried to analyse it a little, in my head, by imagining a deer out at 900m and having a barrel with a length, of say 2" shy of that. You'd be able to point the muzzle anywhere you liked on it's body! I mean, you'd be able to shoot it behind the ear, like a 'BOSS'! Of course, some would argue that the gyroscopic whip, at that distance, would send the projectile off to Mars, but, then again, consistency is the key to accuracy, and if it's consistently sending the bullet off in 'exactly' the same direction, then all that would be required of thee is to simply alter your scope accordingly, no?

Bottom line is, we're only talking 2" difference, between 24 and 26", with a .300 RUM! IMHO 26" barrel is going to be better for powder burning for that particular cartridge, than a 24" would be, regardless of which type of powder you use, fast or slow!

The Truth About Barrel Length, Muzzle Velocity And Accuracy

I think the difference is ask yourself why a 300RUM v a 300 win mag. If you going to use a RUM which burns slower powders and more of it to get the full benifit of using heavier rounds compared to 300 win mag the extra barrel length gives you the full perforance for that CAL, burns the extra powder better and extra speed. 26-28 inch is what all the experts recommend otherwise you might as well just have a 300 win mag etc. At the same time as a hunting rifle its still going to work fine in 24 but isnt everything harder and more expenisve to get, ie brass, ammo etc and more recoil, noise so for the extra downfalls get the very best out of it....and that sounds like a min of 26 barrel. Some in the states use 30. Read a poll on the net on what barrel lenght for a 300 RUM out of 27-30 inch, 50 pcent picked 28, 33 pcent picked 30

Originally Posted by deer243

I think the difference is ask yourself why a 300RUM v a 300 win mag. If you going to use a RUM which burns slower powders and more of it to get the full benifit of using heavier rounds compared to 300 win mag the extra barrel length gives you the full perforance for that CAL, burns the extra powder better and extra speed. 26-28 inch is what all the experts recommend otherwise you might as well just have a 300 win mag etc. At the same time as a hunting rifle its still going to work fine in 24 but isnt everything harder and more expenisve to get, ie brass, ammo etc and more recoil, noise so for the extra downfalls get the very best out of it....and that sounds like a min of 26 barrel. Some in the states use 30. Read a poll on the net on what barrel lenght for a 300 RUM out of 27-30 inch, 50 pcent picked 28, 33 pcent picked 30

Hmm, yeah I'd certainly go a 26"!

Originally Posted by chalkeye

The Truth About Barrel Length, Muzzle Velocity And Accuracy

Very interesting article!
Interesting to note that, on the graphs shown, the 26" barrel, whilst not 'always' the most accurate, was, for the most part, right up there in accuracy, and velocity! I think, for a .300 RUM, a 26" would probably be a happy medium!

Only part of the story though - if you worked up a unique handload for each barrel length it might be a different story.

MOA angle precision is only part of the story.
A longer barrel will give higher velocity which primarily allows slightly reduced wind drift.
That's very useful at your ranges of 800m, where windage uncertainty is more important than gruop size or bullet stability and all the other sources of variation together.
I think you'll find that higher velocity also reduces small errors due to slope, air pressure/altitude and maybe other causes.
We assume you have the range to the nearest metre but errors can occur there too so if you range on a bush behind the deer you introduce a significant drop error at 800m.
I'm talking about stretching from 26" out to 30".
Small differences in magazine length and throating can allow greater velocities too and Brian Litz lists them as a significant "advancement in long range shooting".