Barrell Length

K

Kim Cosstick

Guest
Hi Guys
I would like to know if there is an ideal length for a rimfire BBL.
I know that after a distance the projectile slows down while still in the BBL. Could you tell me this length.
The BBL is 1.1in with no taper for a 14lb gun.
Regards Kim
 
I saw a post on here some time ago that had the length, after which the projectile slowed. I cant find it. Help
 
Supposedly, the .22 rimfire acheives maximum velocity from 16-18 inches after which it begins to slow.
 
Question

Are you more interested in maximum velocity, consistent velocity, or maximum accuracy? Is the barrel length for all three necessarliy the same?

Mark
 
Patriot said:
Are you more interested in maximum velocity, consistent velocity, or maximum accuracy? Is the barrel length for all three necessarliy the same?

Mark
Click to expand...

some shorter barrels iron out velocity variations a bit better than medium length barrels no? Does that work on the longer ones?
 
Patriot
I am after greatest accuracy which would presume would be the most consistant also.
Kim
 
Barrel length, velocity & accurancy

I start by saying most all I "know" I have learned from others. Be it word of mouth or the written word, in magazines, books and posts. I agree that it is generally agreed that somewhere around 17" the standard .22 Long Rifle generates the most velocity. Everyone agrees when shooting iron sights a long sight radius is helpful to accuracy. There is lots of support for short fat barrels producing less harmonics and yielding very good accuracy. A short barrel with a scope may be the best, yet I haven't seen this myself in .22 Benchrest. What I have never read anything about is whether or not a long barrel will reduce velocity variations or add to them. Is it better to just use up all the expanding gas when the bullet exits, or better to let the bullet slow a bit in the barrel, also being sure all gases did their expansion duties. My guess, what the top shooters shoot is probably the best. The centerfire crowd uses barrels that are relatively short for the powder burned and that powder is not fully burned up when the bullet exits, yet they do ok. So I guess I don't really know, but would live to have someone experiment and report. My thoughts at 4:30 this morning.
 
26 and 1/4 inches or more preferably the tight spot in the barrel. If the tight spot is longer so much the better. A short barrel is more likely to have a round go supersonic,bad. A short barrel is more likely to give higher velocity, and thus more wind drift, bad.
 
Found some info, barrel length & velocity

Here is a study that Chief Dave did some time ago. It has to do with barrel length and velocity, as opposed to accuracy. The general concensus is that the 22 LR has completed its powder burn at about 16 1/2". After that there is a gradual loss of velocity due to drag.

"Chief Says : I can answer that EASY.
Here are my " ancient" test notes from when I cut down Ruger
10-22 and 77-22 barrels.
High velocity , Standard velocity == Remington 22LR.
Length,HV&SV in fps
30" 1199 1090
28" 1211 1099
26" 1226 1105
24" 1238 1121
22" 1247 1131
20" 1256 1140
18" 1265 1153
16" 1277 1161
14" 1262 1149
12" 1245 1141

Easy to see that highest velocity came from the 16 " barrel length
anything higher or lower resulted in loss in fps.

About the only real advantages for a longer barrel are 1, longer sight radius when using open sights 2, velocity reduction to keep a marginally fast ammo from going supersonic 3, noise reduction 4, balance 5, just because you like the looks of a longer barrel. Item 2 is about the only thing that may help accuracy.

Good luck. sawdust (I forget where this was posted, sorry, David)
 
I sluged the barrel and it gets loose at about 4in from the end. I guess this is where I cut it off. I find it verry difficult to be exact in the measurment, some advice would be greatly accepted
 
Kim, how does it slug in the other direction, (from the muzzle to the chamber). You will need to slug it more than once to confirm your findings. The bore will tell you where it's best. You do have a large profile barrel, which isn't the norm in rimfire benchrest. It would be hard to tune IMO if you were to use a tuner.

If you don't mind me asking, what action is the barrel being used with?


Joe
 
Last edited:
Joe
The action is a BRNO mod 2 in a McMillan stock. I ordered a barrel for a 7lb12 gun but the barrel that turned up was a 1.1 straight profile and the smith said he could taper it and I said no. Fat barells are common where I shoot. So now a change in plans and it will be a 14lb gun. Barells are harder to get in OZ and we settle for something less than we want sometimes. Harts are verry hard to get and I will try to make this one work as it is brand new. I need some advice on where to cut because it is verry hard to put it back on once it is off.
Kim
 
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