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  #21  
Old 07-12-2011, 10:51 PM
GGaskill GGaskill is offline
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Last year at the NRA meeting they announced they were starting up the line again. I got on the list and in October received shipment. I love it.
Man, I am really glad to see that!


I checked their web site and it looks to me that they are making a batch but are not necessarily going to always have them in stock. Better order now if you want one.
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  #22  
Old 07-13-2011, 01:05 PM
Unclenick Unclenick is offline
 
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They told me production was stopped the first time not because it was unprofitable, but because Epson had stopped being willing to sell them the printer modules in the quantities they needed. I'm guessing the new run required they capitalize a larger quantity than they used to get, and that's why the price is significantly higher. Or perhaps economic desperation made Epson change its mind about quantities, or they found a Chinese replacement and the increase is due to having to set the line up all over again. I haven't asked.
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  #23  
Old 06-17-2012, 08:14 PM
rcolarco rcolarco is offline
 
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When Major Ingalls produced his famous ballistics table, he did not use any time measurement instrumentation at all. He measured bullet drop over known distances and calculated time and velocity.

You can do the same thing using any ballistics program. You have to know (or assume) the BC of your bullet for your actual shooting conditions. Assuming you are capable of shooting a group, shoot a group at 100 yards with dead center hold. Then, using the same sight setting, shoot another group with dead center hold at 200 yards. Measure the bullet drop from 100 to 200 yards. (This may be easier if you shoot the two groups on the same target, and if the groups are fairly small.)

You are probably starting with a rough idea of the muzzle velocity. Plug all the numbers into your ballistics program, and play with the muzzle velocity until the calculated drop from 100 to 200 matches the measured drop.

I have done this several times. I never calibrated the method against a chrono, but trajectories calculated with the MV obtained were good enough to calculate usable sight settings to 600 yards. That's all I need.

You could also algebraically re-arrange the formulas in Hatcher's Notebook to directly calculate MV from measured drop. This is essentially what Ingalls did.
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