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broyal
April 24, 2012, 10:37 AM
Setup-
I have a lot of field behind my house. Picture a huge rectangle. Its over a mile wide and is at least 5-6 miles long. There is no backstop. Just flat vacant earth. There is a dirt road that has barely any traffic. It runs perpendicular to my firing line. It is 1 mile from my firing line. I would like to build a shooting platform 12-15 feet off the ground. If I shoot a .308 from the platform, will the earth absorb and eat my bullet? Ive seen pistol bullets skip accross the dirt. No more than 2 skips. I will build the platform that high so I can shoot above a treeline consisting of evergreens that are around 10 ft tall.
Is a elevated platform and wide open field enough to shoot long range safely? Will the .308 bullet hit the ground and then skip forward another few hundred yards?
Any help would be great. I know the laws and what can happen. I just want to know if a platform would help stop the bullets. I can answer any questions you may have for me.

4EVERM-14
April 24, 2012, 02:17 PM
The potential range of a centerfire rifle cartridge can be several miles. What is not certain is the direction of travel. Every contact with the ground can dramatically change the direction of the projectile. It is not prudent to try to predict the way a ricocheting bullet will react. The only way to be sure of safe shooting is to insure that the bullet impacts directly into a berm, large pile of dirt or sand. Elevating the firing point would only be advisable if it created a more vertical impact area.

broyal
April 24, 2012, 04:39 PM
I understand that it can change direction upon hitting the ground. How much energy is left over after it hits the dirt? How much farther could it travel? And wouldnt the slightly elevated angle help get the bullet traveling down to earth instead of flying parallel to the ground allowing for a greater travel distance? Building a berm is not an option. I would be shooting at targets that are only a few feet off the ground. To me this idea does not seem that bad/dangerous. A change in bullet direction isnt a problem since there is nothing in the area.

jmr40
April 25, 2012, 06:46 PM
Shooting down into the ground you should be OK, but I'd feel better building an earthen berm to catch my bullets. Even then you should be careful of shots that go over the berm and potentially travel for several miles.

You also need to consider. Does all the land for the 5-6 miles belong to you? Could others be in that field at any time? This may be a pretty good spot for a rimfire, but not for a centerfire.

briandg
April 26, 2012, 01:40 AM
any plot of land could have flat surfaced rock or hard baked ground that could bounce a bullet just like a skipping stone, and no matter how high you build your stand, you will not be able to drive them into the ground. Every shot you take may ricochet.

one mile away, you have public land, and those things can and probably will reach that public land if you pop them off of a flat rock.

I'm assuming you have permission to fire onto that land. If you don't have explicit permission, you had better not. If you have permission to shoot on it, either build a small berm with a pile of rail ties and a bunch of dirt, or find a heavy plate of steel to create a bullet deflector trap.

The only other choice you have is to use frangible bullets. They are available.

I don't know what laws you have there, but I'm pretty sure that shooting on or across a road, whether or not you are actually hunting, will be illegal.

briandg
April 26, 2012, 01:44 AM
to address a point I missed, how much energy does a ricochet retain? almost all of it's initial energy in some cases. A little will always be lost in deforming the skin, and a bit will be lost in the change in angle, but most of that energy is just deflected on another path. Think about a vehicle bouncing off of a guard rail on the highway. That is a ricochet. How much velocity does a car lose when it bounces off of a guard rail?

BigMikey76
April 26, 2012, 10:40 AM
The fact that there is a road 1 mile from your firing line is the biggest concern, IMO. It is well established that even rimfire rounds can travel that far under the right conditions, and centerfire projectiles can go considerably farther. Even if you own the land on both sides of the road, you can be pretty sure that shooting over it is a BIG no-no.

Even if it is not a legal violation, it is a huge safety risk. There can be someone on that road, and therefore in your line of fire, at any given time - just because it is rarely used, does not mean it can't be used. I would not take that shot unless I made sure there was a backstop in place to ensure the bullets could not reach the road.

When in doubt, err on the side of caution and safety.

briandg
April 26, 2012, 05:06 PM
for that matter, is there ever foot or bike traffic on that road? You can't count on seeing a car. You may have an entire troop of cubscouts or the local marching band or track team trotting down that road dodging your stray .460 weatherby rounds.

Granted, that sounds like a hell of a lot of fun, tossing rounds overhead while the marching band cowers in the ditch, but that's just me being antisocial.

thedaddycat
April 26, 2012, 07:26 PM
That row of evergreens may be only 10 feet tall right now, but they tend to grow fairly quickly. In a couple of years they will be 15 feet tall, what then? One of the basic firearms safety rules is to have a good backstop. What if you went just past the road to set up your firing like? Would you still have a couple of miles of range free and clear? What's beyond that, hills, woods, a lake?

Art Eatman
April 26, 2012, 09:35 PM
I have a benchrest on my front porch and a backstop at 100 yards which is about five feet wide and about four feet high. Haven't missed it in nineteen years. :)

Most centerfire cartridges will reach out to 2-1/2 to 3 miles, if fired upward at about a 40-degree angle. Odds are that a ricochet, when fired on level ground, won't go much over a mile--but that's just guessing.

briandg
April 27, 2012, 08:31 AM
art, I think you are probably right about the mile range of a ricochet. In most cases it will bounce at the same low angle as fired; that's been found to be true in gunfights, iirc, and hence, combat professionals are advised to remain upright behind cover, rather than hitting the ground. bullets hug the ground under some circumstances.

Yes, you're talking about close to 3 miles, iirc, taken from a military manual on the 1903 or the enfiled, I don't recall. Hitting the ground at a low angle, instead of going airborne at a 40 degree angle will again have the round skimming the ground, and greatly reducing the distance it is capable of going, and any damage to the bullet will cut into velocity.

So, at least in theory, fired at a low angle and bouncing off of hardpan will most likely prevent that bullet from reaching the 3 mile mark. In my and your at somewhat educated opinions, it is at least somewhat likely to go right over that roadway at head level. Do you think?

one last thing. at 100 yards, that bullet, assuming a constant grade from platform to target, is exactly 3 degrees at 15 feet. (180 inches, 1 MOA per inch of elevation above horizontal, 60 inches to 1 degree.

I'm not going to go and dig through ballistics charts to try and figure out the actual flight path, but if it richochets, it might be able to bounce at as high as a 10-20 degree angle depending on the impact and angle of the surface. An exactly equal level of deflection, as if it hit a perfectly horizontal plate would put that bullet at appr 15 feet above horizontal at 200 yards, maybe still climbing. Placed at 200 yards, the angle will be 1.5 degrees, for a 7.5 feet elevation at 1/4 mile.


I've spent a lot of time working this stuff out and researching it. It is still possible that I'm incorrect.

One more consideration is to find out the exact grade of the ground between the stand and both the road, and the planned target site. A surveyors tool can be rented, or even bought relatively cheaply, and the figure can be found with MOA accuracy. If there is a 100 feet high slope between the target and the road, I believe it is pretty unlikely that a ricochet can overcome 100 feet of climb at what should be a low angle. If it bounces at a high angle, it should still come in on the side of the hill.

Lay a mirror perfectly flat on the ground. Float it on a bucket of watermake certain it is totally level. bounce a laser off of it at dusk, and the dot will show up at the exact complement of the initial 3 degree angle.
Gonna need one heck of a laser to see the eventual point of pseudo impact.

Marquezj16
April 27, 2012, 09:01 AM
One thing I've seen about ricochet is they never follow the rules. During some night training, I've seen ricochets depart at a greater angle or different direction than they were originally fired. Could have been a rock or whatever that changes that angle, no ground is perfectly flat.

tobnpr
April 27, 2012, 04:33 PM
I think a relevant question, without getting into unrealistic concerns, is whether the .308 round contains enough kinetic energy at one mile (I think I read 500 ft/lbs is minimum) to cause bodily injury. We're not concerned here about how far the bullet can travel, it's how far it can travel and still have enough retained energy to penetrate flesh deeply enough to cause bodily injury.

Unless, we're talking about the proverbial shooting someone in the eye with an Airsoft gun...

Obviously, a ricochet is going to bleed off energy, decreasing it dramatically.

According to Strelok, the .308 load we use with the 175 grain SMK with a MV of 2,638 fps will have a velocity of 591 fps (wayyy subsonic) and retained energy of 136 ft/lbs at 1,760 yards.

I have read that a hp bullet needs a minimum of 250-300 fps to penetrate flesh...

IMO, if one mile is TRULY the closest anyone can get to your rifle, with some common sense thrown in- as in spotting carefully before shooting- for good measure I wouldn't be overly concerned with a .308.

I tend to think there's been a hunter, or two, that has taken these shots every day with others within a mile of them, and no solid berm/backstop?

BigMikey76
April 27, 2012, 05:16 PM
tobnpr - good points, all. I personally don't know the numbers, so I will not argue with any of your math.
However, there is still the issue of potentially shooting over a road, which, as I understand it, is illegal in most areas. Also, whether the bullet is likely to have enough energy to really harm or kill someone or not, it is still irresponsible to take the chance.
As for the hunting example, regardless of situation, the shooter is responsible for the bullet. If I have a shot that either misses or passes through the target and hits someone further down the line, I can, and likely will be held responsible for any harm on grounds of negligence, all the way up to the level of negligent homicide if my shot takes a human life.

Marquezj16
April 27, 2012, 05:29 PM
According to Strelok, the .308 load we use with the 175 grain SMK with a MV of 2,638 fps will have a velocity of 591 fps (wayyy subsonic) and retained energy of 136 ft/lbs at 1,760 yards.

Even at that speed and energy, it would not be safe for anybody to get hit by that bullet. I wonder if the law would charge you for shooting someone even if it does not penetrate flesh.

BigMikey76
April 27, 2012, 05:46 PM
I wonder if the law would charge you for shooting someone even if it does not penetrate flesh.

They would at least have grounds to charge you with reckless endangerment. Heck, they could probably charge that even if the shot were a near miss.

Buzzcook
April 27, 2012, 06:03 PM
Yow, you own six full sections?

From 15' up you shouldn't have any problems.
But I've never met anyone with that much land that didn't have access to basic earth moving equipment. So throwing up a small berm shouldn't be a big deal.

briandg
April 27, 2012, 07:35 PM
As is argued infinitely on other threads, nobody can predict what will happen when people are added to a problem. If you bounce a bullet off of a car, or god forbid, hit someone, whether there was an injury is completely irrelevant.


The important facts will be that a shooter fired a bullet in a manner that caused it to be a danger to a bystander who has every right to drive down that road. In some countries, you'd be executed for such a thing.

"FOOL! THE GENERALISSIMO DRIVES DOWN THAT HIGHWAY ONCE A YEAR! Take this idiot out and shoot him!"

Major Dave (retired)
April 28, 2012, 03:27 PM
Wouldn't just one or two dump truck loads of topsoil make a big enough mound to stop centerfire bullets? How expensive is that?

Cheaper than hiring a lawyer, I would think?:confused:

briandg
April 28, 2012, 04:51 PM
yep. when you have all of that open territory, there are plenty of options that could work.

Obviously, buiding a sniper tower shows that he's not lacking for funds. I'd personally buy frangible bullets and sleep better at night.

I hope he puts a hog feeder in the middle of that spread and kills some feral hogs.

hagar
April 28, 2012, 09:40 PM
I recall reading some testing done with popular calibers, shooting them at a 30 degree angle or such, and the 7mm mag went the furthest, just over 4 miles. I'd say once a bullet hits dirt that it will not go further than another 500-600 yards at the most. It will normally tumble and yaw and will loose velocity very quickly.

BIG P
April 30, 2012, 12:29 AM
I shoot large bean & corn fields a good bit,The property is slightly down hill toward a river.Being a mile away,My last barrel is 1000yds.Ihave seen a couple rounds skip 2 or 3 times before diggin in,But thats a plowed field & a 300Mag.Most stop within 200yards of impact.A berm is still a good idea if you can.;)

Art Eatman
April 30, 2012, 08:44 AM
As a dump truck owner/driver/loader/dumper I can tell you that one load of six to nine yards of dirt will be quite sufficient for a backstop. :)

If the shooting station is high enough to see whether or not there is a car on the dirt road, I would have no concern about shooting when there is no car on that road.

I really doubt that a ricochet would take a 90-degree turn and still go a half-mile to the side of the property. Way too much energy loss at the impact.

broyal
May 3, 2012, 08:28 AM
Thanks for the replies. Im still not sure if I should build it. I cannot build a berm because we cash rent our fields and I dont have access to any earth moving equipment. I currently only own .223 rifles. I asked about .308 just in case I ever purchased a larger caliber.
The last few post indicate the I should be able to safely shoot down into the field. The first few post indicate that this is unsafe. Mainly due to their worries about people that arent there. Its a service road. Not even a gravel road. Its two dirt tire tracks.
The cost of the tower is hardly anything. Ive got lots of free 4 x 4s and just need a couple sheets of plywood and a couple 2x4s. I will attach one side to a barn for support. I was even thinking about cutting a door way out of the side of the barn and using the loft instead.
Bottom line is that I just want to be able to shoot my rifle from 25-500 yards. No range within a reasonable driving distance to me offers anything aver 100.

BigMikey76
May 3, 2012, 08:51 AM
The last few post indicate the I should be able to safely shoot down into the field. The first few post indicate that this is unsafe. Mainly due to their worries about people that arent there. Its a service road. Not even a gravel road. Its two dirt tire tracks.

Perhaps if you had specified that in the original post, there would have been less focus on the potential issues caused by shooting over a road. We can only go on the the info you provide ;)

Dave P
May 3, 2012, 09:29 AM
With all the wood you have, can't you build a 4x4 box, maybe 1 ft deep? Fill it with sand/ sand bags and you are set to go (until it needs repair). Put it on a trailer, so you can move it for the renters.

Put up warning signs on the trail.


Also, afaik, a high speed (like 3000 fps +) 223 varmint bullet will self destruct on the first impact, whether it is prairie dog or the ground. Any varmint shooter want to chime in on this??