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View Full Version : Your accuracy vs bbl length???



kevmc
01-09-2015, 04:30 PM
What's the difference in accuracy for YOU with different length bbl.'s?
I've got a SW 586 6" that I shoot very well, 1.5" @ 25 yds.
With my SW 66-2 4", I get maybe 3"....
SW 686+ 2.5" = maybe 4".....
Different guns, need different loads, but what difference do you see shooting different bbl. lengths?
How much does your accuracy fall off as bbl. gets shorter??
8 3/8"....7".....6"....4".....snub.....

MT Gianni
01-09-2015, 04:41 PM
I have a 3 1/2" 32 long that is amazingly accurate. I get better accuracy with a 6" K 38 than a 4". I don't see it as bbl length rather than sight length. For me the longer sighting picture makes a difference.

freebullet
01-09-2015, 05:00 PM
Smaller barrels are just as accurate most times it's tough to do well withem. That's mostly attributed to the shorter sight radius. A sure way to find out is to lock them in a rest and find out.

I don't ask a 3" bbl to shoot as well as a 6" because I couldn't shoot the 3" as far and maintain accuracy. For me the lightweight factor of the short barreled gun hurts my accuracy more than the shorter sight radius. I can do better with a heavy 3" revolver than I can with a little 3" pocket autoloader because of the longer sight radius and heavier frame. Even comparing what a guy can do with two 3" barreled guns isn't apples to apples unless fired from a rest.

fredj338
01-09-2015, 05:09 PM
The guns are mech'l identical for accuracy. Clamp them in a Ransom, they'll shoot the same groups +/- the diff in guns. It's the site radius & the shooter. Sometimes a shorter bbl can show better accuracy, less vibration. Not as relevant in pistols but rifle bbls. I have a 1911OM, 3 1/4" bbl, that is more accurate than a couple of my 5" guns off the bench.

kevmc
01-09-2015, 05:27 PM
The guns are mech'l identical for accuracy. Clamp them in a Ransom, they'll shoot the same groups +/- the diff in guns. It's the site radius & the shooter. Sometimes a shorter bbl can show better accuracy, less vibration. Not as relevant in pistols but rifle bbls. I have a 1911OM, 3 1/4" bbl, that is more accurate than a couple of my 5" guns off the bench.

Agreed that they're mech. same, sight radius can be big factor no doubt.
Question is, how much larger are your groups when shooting a, say 4" vs 6" or 7 1/2"?

Shiloh
01-09-2015, 06:12 PM
Longer sight radius is conducive to more consistent accuracy.

That being said, https://www.youtube.com/watch?v=6_b3dAbKoJ0

Shiloh

44man
01-09-2015, 06:15 PM
You need a scope or dot to tell. That eliminates sight radius. The one thing that changes accuracy is velocity achieved with the boolit for stability, not seen at touching distance but is at longer ranges. Even 50 fps can make a gun inaccurate with a certain boolit past a certain distance. A short barrel can be amazing with a load that spins up. I always say you need spin for stability. If you reach spin the short will shoot farther.
When you get to large cases with more powder that can't burn is where they can not get to velocity so a faster powder is needed. That makes boolit choice and hardness matter more. Short makes it harder but if 25 and under, you will not see it.
Even the .500 JRH will shoot lights out at 50 or 100 with a 6" barrel but I would not like to work with 4" or under. My loads will fail.
My 45-70 BFR with 10" was a real chore. Do NOT bring one 4" long to me to find a load! :bigsmyl2:[smilie=l:

fredj338
01-09-2015, 07:29 PM
Agreed that they're mech. same, sight radius can be big factor no doubt.
Question is, how much larger are your groups when shooting a, say 4" vs 6" or 7 1/2"?
Again, depends on the gun. As noted, my 1911OM, a little more accurate than a couple 5" 1911. Generally though, most will shoot smaller groups with longer bbls. My 8" Dan Wesson 44mag is easily twice as accurate off the bench as my 4" M29s.

Wolfer
01-09-2015, 07:37 PM
I've always felt my short barreled revolvers were just as accurate as the longer ones. They just took more concentration to get there.
After a barrel gets so long I start to have more trouble hitting with it. It's a balance thing. For me in standard frame 6-1/2" is about perfect I think. Hard to say for sure since there's not many made.

35 shooter
01-09-2015, 07:51 PM
The main difference i found with shorter bbls. in handguns was sight alignment becomes more critical.The shorter 3" bbl. will be pointing further away from the target than say a longer 7" bbl. given the same amount of sight error with each.
Extend your index finger and point at something, then move it a slight amount to the side. Then bend the same finger in half and do it again. Same amount of movement and your pointing further away.
For me at least, short bbls. go great with older eyes. I can see the sights better than the longer bbls. now.
As has been said here already, put em in a vise and they should all be close, especially with proper powder and load choice for the shorter bbls.

I think 44man explained it best!

rintinglen
01-10-2015, 10:57 PM
In bygone days, I was much prouder of the 595 x 600 I once shot with a Detective Special than the 600 I shot with a 6" M-14. It is not that the short guns can't shoot, it is that I can't shoot them to the limits they have. Younger eyes are a blessing.

44man
01-11-2015, 10:31 AM
I used longer barrels for IHMSA because most of my guns had a sight change of 1,2,3,4". 1 click at 50 meters was 1". You can't do that with short barrels even if accurate. 1 click could be too low or too high. A few thousandths would make you miss if you could not see it at the sights. A scope or dot will solve that.
If you can get stability, the short barrel is not any less accurate, but that can be harder to find. Too much work for me. [smilie=b: