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View Full Version : M1A Barrels - 18" vs. 22"


mellowthunder
January 4, 2010, 11:10 AM
How much is lost between the 18" barrel of the Springfield Scout Squad and the 22" of the Springfield Loaded?

kraigwy
January 4, 2010, 12:31 PM
This will give you an ideal. Its the test we did for my grandaughters science project. We started with a 308 26 in barrel cut it two inches at a time, getting the average velocity of 5 rounds. This was a remington bolt gun, using 180 gr remington factory ammo.

May not be exact for your gun but should be pretty close.


Barrel
26 2826 fps
24 2722 fps
22 2713 fps
20 2677 fps
18 2654 fps
16 2552 fps

Slamfire
January 4, 2010, 06:34 PM
PTR91
18" barrel

150 gr Australian Ball MF83 headstamp (actually 147 grain)

30 April 2008 T = 75 °F

Ave Vel = 2599
Std Dev = 23
ES = 63
High = 2630
Low = 2567
N = 10

poor accuracy

http://img.photobucket.com/albums/v479/SlamFire/Rifles%20various/PTRFullLength079.jpg


M1A Super Match 22” 1/10" 6 groove Douglas

150 gr Australian Ball MF83 headstamp (actually 147 grain)
T = 78 °F 2-May-05

Ave Vel = 2806
Std Dev = 91
ES = 344
Low = 2612
High = 2956
N = 10

http://img.photobucket.com/albums/v479/SlamFire/M1a%20and%20Garand%20Receiver%20Pictures/ReducedRightSiderifle1.jpg

Ruger M77 MKII 26 " Barrel 1:10 twist

150 gr Australian Ball MF83 headstamp (actually 147 grain)

30 April 2008 T = 62 °F

Ave Vel = 2819
Std Dev = 19
ES = 64
High = 2859
Low = 2795
N = 10

http://img.photobucket.com/albums/v479/SlamFire/Ruger%20M77%20Glassbedded/96ReducedRugerM77afterGlassbeddingD.jpg