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Old October 9, 2014, 05:33 PM   #1
mehavey
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Garand [expletive deleted] :-)

OK....

http://imgur.com/a/3kabN

> M1 Garand at 1200
> frames per second

( ...just when you though it was safe to go back into the water, compared against the AR action)
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Old October 9, 2014, 06:06 PM   #2
Mosin-Marauder
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Wow! I'd like to see some like these for the M1 Carbine!
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Old October 9, 2014, 06:13 PM   #3
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Yep, I Likes my M1...

+ so far my method has left my thumb in tact...

My Pop is smiling down on me and at the same time smacking the back of my head saying not to waste ammo!!
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Old October 10, 2014, 06:33 AM   #4
Bart B.
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The unlocking cycle of the M1 Garand and M14 rifles was tested in 1957 by Springfield Armory. The purpose of the test was to determine the average time (in milliseconds) from firing pin contact to:

a. Bullet passing the gas port
b. Bullet exit
c. Initiation of operating rod recoil
d. End of operating rod dwell
e. Completion of bolt unlocking
f. Position of bullet at initiation of operating rod recoil
g. Position of bullet at end of operating rod dwell
h. Position of bullet at completion of bolt unlocking

Three single rounds were fired from each of three M1 and three M14 (T44E4) rifles. The ammunition used was M2 AP for the M1 rifles and armor piercing (T93E1 or T93E2) cartridges for the M14 rifles. Each rifle was fully loaded for each series of three shots. High speed motion picture cameras (operating at 6,000 to 7,000 frames per second; about 1 frame every .015 millisecond) and flash strobes were used to record hammer fall, bullet exit, operating rod movement and bolt unlocking during each firing sequence. Lumiline screens were used to record average bullet velocity at a distance of 53 feet forward of the muzzle. The film was analyzed to obtain the data below. Average values were computed from the high speed film as follows:

Data Item ........................................................M1 Rifle ..............................M14 Rifle
Type of gas system ...........................................gas impingement ...................gas cut-off and expansion
Location of gas port from muzzle .........................1.5 “ ...................................8.0 “
Gas port diameter .............................................0.0793 “ ..............................0.0768 “
Barrel length ....................................................24 “ ....................................22 “
End of hammer fall ............................................0 milliseconds ........................0 milliseconds
Bullet passes gas port .......................................1.31 milliseconds ...................1.01 milliseconds
Bullet clears muzzle ...........................................1.36 milliseconds ...................1.25 milliseconds
Initiation of operating rod recoil ...........................1.58 milliseconds ...................1.53 milliseconds
End of operating rod dwell ...................................2.89 milliseconds ..................3.57 milliseconds
Completion of bolt unlocking ................................4.07 milliseconds ..................5.00 milliseconds
Amount of bullet travel at start of op rod recoil .......7.2 “ past the muzzle .............9.2 “ past the muzzle
Position of bullet at end of op rod dwell .................50.2 “ past the muzzle ..........76.1 “ past the muzzle
Position of bullet at completion of bolt unlocking ......88.9 “ past the muzzle .........123.0 “ past the muzzle
Average bullet velocity ........................................2735 feet per second ...........2733 feet per second

Reference: Springfield Armory Technical Note SA-TN11-1094 dated 16 Dec 1957

With both service rifles, it was common for competitive shooters to cut a turn or two off the ejector spring. Sometimes, ejector springs were so strong and the timing cycle was such that empty cases would be spun backwards over the rear sight going under the bill of their ball cap then bouncing off shooter's forehead. Very hot fired cases would often come to rest on the shooter's glasses' bridge against their forehead burning the skin (happened to me; twice). By cutting half a turn off at a time then testing ejected cases' trajectory, fired cases would be pushed forward and to the right piling up a couple feet away from the rifleman.

Last edited by Bart B.; October 10, 2014 at 06:49 AM.
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Old October 10, 2014, 07:07 AM   #5
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This is awesome! Thanks so much for sharing this!
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Old October 10, 2014, 07:21 AM   #6
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PING!!
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Old October 10, 2014, 09:06 AM   #7
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Wow! That is information on the M1 that I will never need in this lifetime
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Old October 10, 2014, 09:37 AM   #8
4V50 Gary
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Thanks. I saw the link the other day at another website and couldn't get it to run. Now it does.
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Old October 10, 2014, 10:48 PM   #9
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+1 on the thanks. It's a very interesting video.
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Old October 11, 2014, 08:30 PM   #10
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Cool stuff. Thanks.

I know and love the AR, but darn if there isn't something about the Garand that just feels *right*.
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Old October 11, 2014, 09:01 PM   #11
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Pretty dang sweet! I love firearm technology, old stuff, new stuff - it's all awesome!
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Old October 13, 2014, 02:29 AM   #12
bamaranger
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thanks

Neat video, thanks.

Bart B. What a bunch of data!!! And the conclusion??
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Old October 16, 2014, 08:54 PM   #13
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Another big thank you.
Makes me appreciate my Garand even more, now.


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Old October 23, 2014, 07:15 PM   #14
Bart B.
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I draw no conclusions. I'm just the messenger.

It may explain to some why Garands could be rebuilt and be almost as accurate as bolt action rifles. None of their parts move until the bullet is out of the barrel. If all parts are in battery exactly the same for each shot fired, the barrel whips and wiggles the same way while the bullets go through it.

Last edited by Bart B.; October 23, 2014 at 07:20 PM.
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