M1 Garand at 1200 frames per second

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That's pretty. The Garand looks like it has a smidge more grace. Wasn't aware it cycled faster too. Neat.
 
Nice site. Love watching those old war horse's shot. That twang of the clip flying out.
 
Quite a bit of op-rod bounce.

It would be interesting to see if a M-14's op-rod bounced that much, especially during auto-fire.
 
Howdy

Great video. It gives one great respect for the designers of these firearms who were able to tweak the designs so they became reliable when mass produced. They probably had to go through several prototypes until they got it right.
 
Check this out

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

Scroll down to see AR15/Garand comparison.
I notice that the M1 has a much smoother and shallower loading path for the new cartridge, and that there is almost no gas blowing back through the action.
The op rod has the bolt going from lock to unlock in 2 frames which is 1/600 of a second...Nice!
The fact that it ejects the clip out the top automatically is just freaking amazing, and that it all runs on just one spring. It is like some kind of magic show.
 
Seeing the comparison of cycling rates reminded me of this video from Forgotten Weapons, which mentioned problems with trying to get a BAR magazine to work with the M1 converted to full auto. Winchester discovered that the M1's bolt generally cycled faster than a stock BAR mag spring could respond:

 
I notice that the M1 has a much smoother and shallower loading path for the new cartridge, and that there is almost no gas blowing back through the action.
The op rod has the bolt going from lock to unlock in 2 frames which is 1/600 of a second...Nice!
The fact that it ejects the clip out the top automatically is just freaking amazing, and that it all runs on just one spring. It is like some kind of magic show.
They are amazing mechanical puzzles/functional art. Coolest rifles ever, IMO.
 
I notice that the M1 has a much smoother and shallower loading path for the new cartridge, and that there is almost no gas blowing back through the action.
Yup. One of the biggest downsides of the star bolt design is that the feed geometry is a lot more complex.

As someone who does high speed videography, the AR is worse than a blowback action when it comes to filming. Blowback guns don't really shoot much gas out to the side. It goes strait back into the action. I can use a macro lens and get within a couple inches of the bolt without worrying about the lens getting meaningfully coated. An AR? Forget the macro lens, you can't get that close without risking the lens.
 
We have four full auto M-1s in the Museum. All were 1944 experiments. Tag# s 6854 and 6862 employ a selector switch and a connector assembly that later appeared on M-14s. They have been modified to accept a magazine. Whether this was a BAR mag or some other design, I know not. Tag # s 6861 and 6846 have a different method to achieve automatic fire. It resembles a BM-59s. The selector lever is on the left side of the receiver and not visible. These latter two raise the obvious "What the hell were you thinking?" question. They still employ the 8 round clip! :what: Brrrrrrr PING!!!

All four were obviously in the middle of some rather bizarre looking muzzle brake experiments. I have never examined them all that closely other to determine the above mentioned features. Just looking at the pic, I see the relief cut for the op rod on the rear hand guards, not so widely flared front sight protective wings and square cut op rods, so I'm guessing the bottom three are Springfields. 6854 doesn't appear to have the relief cut for the op rod (they just let the op-rod beat its own clearance cut into the wood ) and the front sight wings appear to be more widely flared, so I'm guessing it is a Winchester.

Guess I won't be able to find out for sure until the Museum re-opens!
 

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Always cool to see what speed blurs made keen and visible.
Since they were using slide rules and the like, they were careful about all sorts of things.
So, they could factor in modulus of elasticity.
It took a lot of singular calculations, and, it you wanted a quick result, you hired more calculators.
And, if something was really critical, they had things like spark photography to capture things at very high speed.
So, John C. was using more than stone knives and bear skins.
 
Feed angle is necessarily steeper for one thing. The bolt head diameter is effectively greater so the next round has to be lower relative to the bore. Plus you have to figure out how to feed bullet tips across a couple of square gouges in the barrel extension, which are quite a ways back from the actual start of the chamber.
 
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