Short barreled 270?

MD

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If you compare velocity and longer range (over 200 yards) bullet performance in a 270 with a 20.5-inch barrel compared to performance out of a 22-inch or 24-inch barrel, how much effect does that have on terminal velocity and accuracy out to 300 yards for example?
 
I've got a 20" barreled .270, I get 2950fps with handloaded 130's.
100 fps is nothing in the real world, as I've chronied some 22" .270's shooting factory 130's that couldn't make 2900fps.

Lets face it too much time is spent drooling, and reeling over numbers, when such time is better spent behind the trigger.
 
A couple/few years back Guns magazine tested more than a dozen 270 Win's.

The jist of the their study was to prove that some mfgs/models were "faster" than others and that factory ammo velocities were over-rated by the ammo companies (surprise I know - they wouldn't lie, would they?)

Anyhow, as it pertains to your question they found "in general" that for every inch the barrel is less than 24", which is the "typical test length of the 270 Win", you lose about 30 fps (at the muzzle) - so 60 fps less with 22", 120 fps less with a 20" barrel etc.

They also noted that Browning's, specifically the A-bolt were consistently 15 fps "slower" than others, all else being equal (just a note to show that unless you chronograph YOUR rifle you are "guessing" at best based on the ballistics the ammo company gives you).

Here is some specs from Hornady with a 270 Win shooting their 130 grain American Whitetail (interlock).

With a 24" barrel - 3060 fps/muzzle and 2391 fps @ 300 yards

With a 20.5" barrel using the results from Guns magazine you would be about 105 fps slower at the muzzle or

2955 fps @ muzzle and 2302 fps @ 300 (Hornady ballistics calculator)

So by the time it gets to 300 yards, since the bullet is slowing while in travel, it would be 389 fps slower than if shot with the longer barrel in the SINGLE cartridge comparison, all else being equal.

Shorter barrels are not necessarily any "less accurate" than longer barrels, BUT they are more (influenced) by the steadiness of the shooter. The longer the barrel generally the more "accurately the SHOOTER can shoot" because any minor twitches/shakes have less effect on the path of the bullet.

(think shooting with a pistol compared to a rifle at a 50 yard target - just about every shooter will be "more accurate" with the longer barreled firearm).

Some newer powders used in factory ammo (Superformance as an example) claim to lose less velocity than older combo's when used in shorter barrels.

The bottom line is, there are so many variables that it's tough to give a definitive answer.

But "in general" a shorter barrel will shoot a lower velocity at "any given range" than a longer barrel AND the "average shooter" will shoot more accurately with a longer barrel but the gun itself is "no less accurate" simply because the barrel is shorter - if you do your part a 20" barrel will shoot just as "accurately" as a 26" barrel, just a little to a lot slower depending on what you stuck in the tube...
 
There can be greater variation from one barrel to the next than will be noticed from one barrel length to another...........the only definitive change that can be said will happen for sure is that velocity will go down if you shorten YOUR barrel.
I have played with 7mm RMs that had a 200 fps difference with the same load in the same length barrels. I have also noted a consistent velocity advantage to hammer forged barrels over cut or buttoned barrels.
Way back Ruger barrels used to be all over the place with groove diameters, some of them were super fast (if you put the powder to them) and some would pressure out at a mid range load and were relatively slow for caliber/cartridge.
Accuracy actually favors a shorter heavy barrel while velocity favors a long barrel........as far as shooter accuracy with barrels of different lengths goes I have to call BS........that is a left over from days of old, using open sights where the longer sight radius did make a significant difference in shooter accuracy, with modern optics that whole scenario is out the window........I have seen bench rifles with 20-21-22" barrels and some with 30" barrels, but generally speaking the longer barrels are for greater velocity for extreme long range shooting. The short stiff barrel is less influenced by vibration of the bullet moving down the bore so it has much less pronounced nodes and a much larger "sweet spot", making it much easier to get supreme accuracy from.
Shooter accuracy is totally subjective so to pronounce that longer barrels are shot more accurately than shorter ones is a completely subjective statement and as such is impossible to support with facts. If it were true then all winning bench shooters rifles would have 30"+ barrels, and they do not, so.............
 
Galamb you spend to much time on the Internet . Just comment on one of your statements shorter bbl' s are more accurate than longer bbl's that is why benchrest rifles have short bbl's Al so as far as fps a bbl with a tighter note will yield higher fps .
 
One thing that is certainly going to change is muzzle blast. The shorter the barrel, the greater the muzzle blast. I had a Colt Saur in .308 and it had a 20 inch barrel, as I recall. Even with proper muffs on, the muzzle blast was absolutely deafening.
 
Read carefully gentlemen. glamb never said that long barrels were inherently more accurate than shorter barrels, he simply noted that it was easier to aim a longer barrel (with no mention of sights, I assumed his comments were based upon rifles with open sights). With a scoped rifle there should be no difference in aiming accuracy. His reply reinforced everything I believe about barrel length vs velocity and aiming barrels of different lengths with open sights.
 
While I have yet to proclaim any barrel "fast" or "slow", I have seen some dramatic variations from rifle to rifle.

Here is an example that reinforces c-fbmi's statement regarding earlier Ruger barrels.

I owned [at the same time] 2 Ruger #1 rifles chambered in 30-06. One was a #1 AB [22" barrel] the other a #1 B [26" barrel]

Using the exact same recipe in both rifles, the #1 AB with the shorter barrel consistently beat the #1 B by 120 fps

Another illustration of difference. I have a 700 CDL in 270 [24"] I also have a 270 in a Weatherby Vanguard S1 [24"] Sorry Doug, I know how you feel about the 270, lol :)

With a specific load of Vihtavuori N165 and the 140 AB, I averaged 2995 with the Remington. Working up with the same powder/bullet in the Vanguard, I had to stop 1.5 full grains below the load used in the Remington.

Guess what? Chronograph shows 3022 avg in the Vanguard. Obviously some difference in those two.

This has happened to me frequently enough for me to realize that rifles display individualistic characteristics that may not be easily explained.

As for accuracy, with optics, one is likely to have better accuracy with a short stiff barrel, than with a long, whippy one.

Regards, Dave.
 
IMO if you are worried about velocity then don't go with a short barrel. That being said I like short barrels though, I don't need to shoot further than 250 (heck, even 200) yards very often so an extra 150 fps isn't something that's going to do me much good. My recipe for success is based around hunting places that nobody else goes. Lugging a rifle through miles of thick bush and steep terrain, the shorter barrel is something I appreciate each and every time I'm out hunting. I wont bother with a rifle that has more than 22" of barrel and keep my scopes fairly small, 20" of barrel and irons sure make the miles more enjoyable though.
 
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