Technical problems with a 5000 yard shot

[Hoffer]

Going thru some numbers on a theoretical rifle at 5000 yards using AB app
Specs
375 bullet / 400 gr CE lazer @ 3500 fps
Density altitude 0
Wind 0

337.4 MOA
11.8 sec flight time
Altitude at max arc 1400 ft
Standard rifle prone w/ bipod shoulder to bipod length 24"
0 moa rifle (theoretical)

.001" movement at either shoulder or bipod or combination of both during firing is 7.5" deviation at 5000 yards (1 hair is .003")
2 fps difference in load (3502 fps) 337.0 moa .4 moa off = 20.94"
5 fps difference in load (3505 fps) 336.4 moa 1.0 moa off = 52.35"
Combination of .001 shooter deviation and 5fps muzzle velocity 59.85" off

Now throw in a true 1/4 moa rifle and shooting mat that moves around - easily double that.

Then throw in some wind and wind reading from ground level to 1400 ft agl

There's always that pesky dispersion problem too

Sounds simple

 

[mstephenson51]

Yeah, thats a crazy problem. Makes you wonder how the heck the navy scored any hits ever with battleships shooting 30-40 miles.

 

[Fursniper]

I would add to that that 3500 fps is quite overly optimistic for a 400 grainer in a 375 CT. A lighter bullet in a Snipetac maybe, but not a 375. So up the flight time a bit for even more troubles!

 

[Hoffer]

I would add to that that 3500 fps is quite overly optimistic for a 400 grainer in a 375 CT. A lighter bullet in a Snipetac maybe, but not a 375. So up the flight time a bit for even more troubles!

375 cal was probably not the correct wording - 375 bullet with that ever it takes to get it going 3500 fps. 375-416 / 375-50 possibly

edited to correct spec in original post

 

[Fursniper]

https://en.wikipedia.org/wiki/16%22/...ber_Mark_7_gun

What did the Navy have that reached farther than this?

Nothing, at least in the size of a mark 7 gun. In fact mstephenson was being a bit overly optimistic as well as the Iowa class battleships fired a 2700 lb projectile (wonder how many grains THAT is lol) just under 20 miles with accuracy enough to at least hit anything, not 40 miles. 27 miles was about as far as they could fling one of those babys out of those 66 foot long 16" barrels and it took just under 700 pounds of powder to do that! All without ever a muzzlebrake and nobody complained about the recoil ha ha! Here's a little video for fun.

https://youtu.be/dVvEPTYrcXA?t=151

M.E. Phillips, Captain, US Merchant Marine (retired)
Aka Fursniper

 

[mstephenson51]

27mi. my bad. LOL Still, My thought was on MOA errors then going out long distances.... Point was: crazy hard the farther out you go. IE exponentially harder.

 

[Pesekcw]

Nothing, at least in the size of a mark 7 gun. In fact mstephenson was being a bit overly optimistic as well as the Iowa class battleships fired a 2700 lb projectile (wonder how many grains THAT is lol) just under 20 miles with accuracy enough to at least hit anything, not 40 miles. 27 miles was about as far as they could fling one of those babys out of those 66 foot long 16" barrels and it took just under 700 pounds of powder to do that! All without ever a muzzlebrake and nobody complained about the recoil ha ha! Here's a little video for fun.

https://youtu.be/dVvEPTYrcXA?t=151

M.E. Phillips, Captain, US Merchant Marine (retired)
Aka Fursniper

If I have my calculation correct it is 18.9x10^6 grains

 

[Fursniper]

If I have my calculation correct it is 18.9x10^6 grains

It's been a long time since college but I think that works out to eighteen million nine hundred thousand grains. A lot of "bullet" lol!

 

[ELR researcher]

375 cal was probably not the correct wording - 375 bullet with that ever it takes to get it going 3500 fps. 375-416 / 375-50 possibly

edited to correct spec in original post

Is there a question in there (or your original post)...or just commenting?

 

[Hoffer]

Is there a question in there (or your original post)...or just commenting?

Fursniper was commenting that a 375 CT running at 3500fps was optimistic. Perhaps the wording in the original post might have made it seem that way. Was proposing a .375 projectile at 3500 fps. Perhaps a 375-416 or 375-50. Anything that can can push a .375 bullet at those speeds. Maybe even a 375-20mm ;' )

 

[Pesekcw]

It's been a long time since college but I think that works out to eighteen million nine hundred thousand grains. A lot of "bullet" lol!

The tecnical term we use here in the oilfield is "Metric Shit Tonne"