22 LR how much barrel needed?

[lefteyedom]

At about what barrel length does a 22lr reach it max velocity?

I am building a little squirrel gun out of s 10/22 with a .920 barrel 20" long. Thinking of shorting it down to 16.5 inches. Any ideas?

 

[BerettaRacer]

I've seen posting for that over at rimfirecentral.com, offhand can't remember the exact figures. 16 1/2 to 20 shouldn't be much of an issue, but if I remember longer barrels will definitely slow muzzle velocity.
I shoot local bullseye matches with a 20" bull but building an AR-22 with a 16" TacSol.

 

[Bailey Boat]

I've done chrono tests in the past and the velocity begins dropping (not a bunch though) when you go below 18" or so....... If I'm cutting a barrel I never go shorter than 18 to 19"........

 

[P.B.Walsh]

BerettaRazor, why/how would a longer barrel make less velocity?

 

[Jim Watson]

The friction of bullet vs barrel is supposed to outweigh expansion of the powder gas in a long barrel. The conventional wisdom is that .22 lr maxes out as short as 16-18".
One of our guys ran an actual test with five CZ rifles of different barrel length. Not as definitive as cutting off the same barrel an inch at a time, but I would not ask him to sacrifice his 28" Ultra Lux for the purpose.

Highest velocity with anything but CB caps was from the 22.5" barrel, lowest from the 28.6".

Details at:
http://rimfireshooting.com/index.php?showtopic=3340&st=20
post no 34.

 

[lefteyedom]

A short .920 barreled 10/22 should make a dandy walk about rifle. It would seem that 16.5 would be ideal.
Thank for the feedback

The following information is from Mark White's book "The Ultimate Ruger 10/22 Manual and User's Guide" . Apparently, he cut a 28 inch barrel two inches at a time and measured for muzzle velocity.

Ruger 77/22; Remington Standard Velocity .22 LR ammunition
Barrel Length/ Velocity
28 1095
26 1107
24 1119
22 1129
20 1138
18 1149
16 1157
14 1149

 

[gunnie]

don't recall where, but i have read that after 16", 22lr powder is consumed. above posting confirms this. the old school target 22lr rifles had longer bbls to slow down standard velocity ammo below the speed of sound. note velocity for a 24" bbl.

same also helps slow the movement of the bbl when holding it off hand. the longer the pendulum, the slower it swings.

gunnie

 

[Jubjub]

My 10/22 squirrel gun has a 16.5" barrel, but it's to maximize handiness in the woods, not muzzle velocity. I shoot subsonic hollow points in it. It seems like supersonic crack of a high velocity bullet disturbs the critters an awful lot more than just the pop at the muzzle of a subsonic round.

 

[Claude Clay]

http://www.ballisticsbytheinch.com/

no listing for 22LR but has other interesting info.

16.5 is best cause it looks so good when you type it

 

[JohnBT]

Does it take max velocity to kill a squirrel these days? Must be 'roid squirrels or something else in the water they're drinking. I've killed them with bb guns. You just have to sneak up close.

John

 

[rangerruck]

16 inches will do it; also it is the legal lowest limit. After that, a 22 rounds starts a very slow, slow down process. So your guess is good to go.