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Post by vadupleix on Apr 4, 2014 11:39:49 GMT -5
Hi guys, I just got my inokatsu 2011 m4 and want to cheak the FPS out of it to make sure if I can take that to the game. And I found this article on the redwolf "http://www.redwolfairsoft.com/redwolf/airsoft/BulletDetail?bulletID=34" which basically gives the relation between FPS and soda can penetration power. The problem is that I'm using 0.25g bb instead of 0.20g as that's the only bb I've got, and the result is I managed to penerate all sides including bottom and central which falls into the 520 to 540fps/0.20g interval. Now my question is what actual fps will I have if I'm shooting 0.20g bb as 520+ is not even close to the 400 fps given by inokatsu. Thanks!  |
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Deuce
New Member
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Post by Deuce on Apr 4, 2014 11:49:10 GMT -5
With that test, it doesn't really work today. Our pop/soda cans are typically a lot thinner then they used to be and that test is fairly old. If you want a true answer to your FPS question, you'll have to find a good chrono. Now if your M4 is, for some screwed up reason, 520-540 FPS there is no way you will be allowed to use that anywhere. I'm sure you're aware that anything that "hot" has to be permanent semi-auto only. Basically my overall advice is find a chrono and some .20s to get a legit measurement.
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Post by vadupleix on Apr 4, 2014 12:44:11 GMT -5
With that test, it doesn't really work today. Our pop/soda cans are typically a lot thinner then they used to be and that test is fairly old. If you want a true answer to your FPS question, you'll have to find a good chrono. Now if your M4 is, for some screwed up reason, 520-540 FPS there is no way you will be allowed to use that anywhere. I'm sure you're aware that anything that "hot" has to be permanent semi-auto only. Basically my overall advice is find a chrono and some .20s to get a legit measurement. That explains. Just noticed that the article was written 14 yrs ago. Thanks |
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Deuce
New Member
Posts: 313
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Post by Deuce on Apr 4, 2014 12:48:38 GMT -5
With that test, it doesn't really work today. Our pop/soda cans are typically a lot thinner then they used to be and that test is fairly old. If you want a true answer to your FPS question, you'll have to find a good chrono. Now if your M4 is, for some screwed up reason, 520-540 FPS there is no way you will be allowed to use that anywhere. I'm sure you're aware that anything that "hot" has to be permanent semi-auto only. Basically my overall advice is find a chrono and some .20s to get a legit measurement. That explains. Just noticed that the article was written 14 yrs ago. Thanks No problem man. |
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Post by X on Apr 4, 2014 13:46:12 GMT -5
Besides the fact that it's old .25g BBs completely ruin the test. The test might actually still be valid. I can't say for sure, but I can say that using .25g BBs will invalidate the test. You have to use a .20 and place the can 1" (I think? coming from my memory) from the barrel.
If you look in the article you will see even red wolf warns you of this...
I'm not a physics major, but I believe that using a heavier BB will increase the penetrative ability. My own theory which I haven't yet proven, is that a heavier BB is in the barrel longer giving it a higher energy, but lower FPS than a lighter BB. Someday I'll get around to gathering some actual scientific data to back that up. Until then it's just a theory.
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Post by vadupleix on Apr 4, 2014 20:49:12 GMT -5
Besides the fact that it's old .25g BBs completely ruin the test. The test might actually still be valid. I can't say for sure, but I can say that using .25g BBs will invalidate the test. You have to use a .20 and place the can 1" (I think? coming from my memory) from the barrel. If you look in the article you will see even red wolf warns you of this... I'm not a physics major, but I believe that using a heavier BB will increase the penetrative ability. My own theory which I haven't yet proven, is that a heavier BB is in the barrel longer giving it a higher energy, but lower FPS than a lighter BB. Someday I'll get around to gathering some actual scientific data to back that up. Until then it's just a theory. I understand your point and I have seen similar sayings elsewhere that heavier BB will have higher muzzle kinetic energy but even though the difference can't be this big. I might still need a chrono to see what the story is Thanks |
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Post by Kjones on Apr 16, 2014 2:00:57 GMT -5
I would say the can test is still pretty accurate when done with .20 and with the can free to move. I just did test before the last farmington game to pre-adjust my NPAS in my WE M14 and it got it really close to what I though it was ( 326 fps)
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