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barrel length

Posted: Fri Jan 16, 2009 2:23 pm
by Eric-WD
I am sitting here with too much time on my hands and thinking which is dangerous.

I once saw an article in which they tested 22 LR ammo for velocity from different length barrels. They took a 22 rifle shot ten round through it checking velocity. They then cut an inch off n re-crowned the barrel and did it again. They did this down to 16 inches, It turned out that with the limited powder capacity of the .22 the 16 inch barrel gave the highest velocity.

I saw another article stating that while lock time is important also important is the time the bullet spends going down the barrel, the longer the barrel the more time the shooter has to pull the shot. An example of this is short barreled air rifles with shrouds to extend the sight radius for iron sights. Also short barreled bench rest rifles.

Considering this wouldn't the

Posted: Fri Jan 16, 2009 2:52 pm
by silhouette13
speaking of too much time.... barrel length and velocity would depend on the speed of a specific load, for example if you shot stingers out of a long enough barrel they would leave at std velocity( sub sonic) and also if you shot faster loads out of a shorter barrel you could get to where a 16" barrel would be optimal for standard loads . my vote would be for a 10" tube for short barrel travel time with crazy fast ammo and a bloop tube so i didnt look silly. time is a terrible thing to waste! :P

Posted: Fri Jan 16, 2009 4:13 pm
by malinois
I shot a barrel like that for many years the rifled section was only 16 inches but the barrel was closer to 30 inches with sliding weights on the end it was highly accurate probably the best shooting tube I ever had but I found that it was a whole lot eazier to just shoot the sporter across the course and become proficient with the one rifle. I shot it that way for 20 years

Posted: Fri Jan 16, 2009 9:39 pm
by ShooterP14
I love it when people start worrying about the esoteric minutia (you like that one?) of shooting SB.

I did some number crunching (cuz I'm a geek and that's what I do) comparing barrel length and velocity. The difference in flight time in the barrel between a 16" and 30" barrel using some slow ammo (600fps) is ~ 2mS (.002 seconds). If your ammo velocity is near Mach 1 then the difference is down to 1mS. The difference between the fastest in the shortest barrel and the slowest in the longest barrel is 3mS. Note: I am using instantaneous velocities, it should be close enough to make my point and I'm not doing any calculus at 11:30 pm.

Now assuming the animals are ~4 moa in width and assuming a center hold, it would take 2+ moa to pull the shot off target. At these velocities, you would have to have the gun rotating out of position at ~ 8.5 deg/sec (min). A bank of targets is ~ 36 moa wide (5 targets/4 spaces). At this rate you would have to sweep the whole bank of targets in .07 sec to simulate the equivalent angular velocity it would take for the bullet traveling down the barrel to make any difference.

Having said all that, unless you are a prone shooter using a flintlock don't sweat the small stuff. Forget about velocity and lock time. You're better off thinking about your position, breathing and follow through. Just get a rifle that shoots straight and some ammo it likes and practice.

Get out there and shoot and have a good time! Just remember, the guy who works out all these infinitesimal details will get beat by a 14 year old girl with a borrowed rifle every time!

Posted: Sat Jan 17, 2009 1:52 pm
by malinois
I thought thats what I said....just have fun.

Barrel lenght

Posted: Sat Jan 17, 2009 7:24 pm
by Evelio Mc Donald
A standard velocity 22 LR will reach maximum velocity at about 16" the only reason to have longer barrels is because it will stabilize the bullet for better wind resistance at longer ranges, say up to 100 to 150 meters, also the fact that for off hand shooting, a longer barrel will put more weight in the front which will slow down the normal movement that you would experience with a lighter shorter barrel.
For BR 50 type competition an 18" heavy tube is the way to go.
Evelio

Posted: Sun Jan 25, 2009 8:06 am
by Jerry G
So.... if you have a bbl long enough to be legal in Canada and have a weighted bloop tube you should be there.

Seems to me that was what we were shooting 20 years ago.

barrel

Posted: Sun Jan 25, 2009 9:04 am
by Evelio Mc Donald
Jerry
Bloop tubes are only allowed in the Standard class, you can't use them in Hunter class.
Evelio.

Re: Speed is an enemy of accuracy

Posted: Sun Jan 25, 2009 10:15 pm
by kevinbear
If your bullet leaves the muzzle at supersonic speed it will slow to subsonic down range, during this transition it becomes unstable for an instant, the result is loss of accuracy, hence the domination of subsonic target ammunition. Also note that target rifle ammunition is designed for 20"+ barrels with this concept in mind. Next time you

Posted: Mon Jan 26, 2009 2:13 am
by #57
Just remember, the guy who works out all these infinitesimal details will get beat by a 14 year old girl with a borrowed rifle every time![/quote] Yea, What he said! #57

Posted: Mon Jan 26, 2009 5:17 am
by Bob259
#57 wrote:Just remember, the guy who works out all these infinitesimal details will get beat by a 14 year old girl with a borrowed rifle every time!
Yea, What he said! #57[/quote]

That's why I laugh when I hear the complaints about the 'custom' hunter rifles.... It's not the rifle it's the nut behind it.

Why we do it

Posted: Mon Jan 26, 2009 7:57 am
by kevinbear
It's human nature to analyze things around us in detail, thats why were the most successful species on the planet.
And I love it when some 14 year old without any mental baggage beats me, having the knowledge but not letting it weigh me down means I have to concentrate and forget about alot of other things in life that may not be as enjoyable as shooting silhouette.

Re: Why we do it

Posted: Mon Jan 26, 2009 8:02 am
by Bob259
kevinbear wrote:..........I have to concentrate and forget about alot of other things in life that may not be as enjoyable as shooting silhouette.
Or more enjoyable :wink:

Re: Why we do it

Posted: Mon Jan 26, 2009 8:09 am
by kevinbear
[quote="Bob259"][quote="kevinbear"]..........I have to concentrate and forget about alot of other things in life that [b]may not be as enjoyable [/b]as shooting silhouette.[/quote]

Or [b]more[/b] enjoyable :wink:[/quote]
Ditto that buddie, this is my 26th season of silhouette and as I not quitting anytime soon!

Posted: Mon Jan 26, 2009 10:08 am
by shakes
Its not the size of your barrel, its how many targets you can knock down :wink: At least thats what I've always been told. :lol: