Given that it seems to be mainly marketed as a world beating sniper rifle, how far away (real world) could you consistently hit a man’s head sized target (say a cantalope) with that setup?
It depends. Are you talking about…
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The inherent accuracy of the rifle itself? In other words, the accuracy of the rifle if you mounted it in a vice?
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The accuracy of the rifle + shooter for a world-class shooter (e.g. Skip Talbot or Carlos Hathcock)?
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The accuracy of the rifle + shooter if I’m shooting it?
As you might suspect,
accuracy of #1 >> accuracy of #2 >> accuracy of #3
Nice! I had an AR-50 for a while, but had to sell it get some money together for a SR-25. More practical, but it doesn’t awe the firingline like the AR-50 did…
Not a beat a point to death, but I am curious, and largely ignorant of long range rifle competition performance parameters. If this thing is such a precisely engineered, long distance target rifle how much (real) difference is having a “world class” shooter behind it going to make? You (I’m assuming) put it on the tripod, make windage and elevation etc. adjustments, sight in take a breath and squeeze the trigger. What makes the Talbot or Hathcock competitors any more adept at doing that than you in terms of final accuracy?
I can understand in shooting handheld pistols and shoulder mounted guns, that there’s a lot physical coordination involved. On the other hand with a tripod mounted rifle you fire in the prone position. If hardware is relatively the same, what’s going to make one person that much better than the other in a process that seems fairly mechanical vs the other types of shooting?
I take it the “BFG” is short for “Big Fucking Gun”. Interesting design, bet it packs a wallop.
Astro:
There are many factors that affect accuracy. And the longer the range, the more variables there are. Furthermore, long range shooting tends to amplify errors that are occurring back at the gun.
Here are some off the top of my head. And something tells me I’ve only thought about 30% of them…
Rifle Parameters
Quality and mechanics of trigger group (sear, hammer, one stage, two stage, or three stage trigger)
Trigger force
Headspace
Dimensional precision of barrel
Dimensional precision of chamber
Cleanliness of barrel
Smoothness of barrel
Barrel material
Length of barrel
Wall thickness of barrel
Type of rifling
Twist rate of rifling
Land vs. groove thickness
Type of muzzle break
Pivoting axis of rifle during firing
Amount of muzzle climb
Ruggedness /accuracy of the scope
Magnification of scope
Parallax of the scope
Light gathering capability of the scope
Scope reticule
Barrel temperature
Ammunition
Ballistic Coefficient
Bullet concentricity
Bullet mass
Bullet center of mass
Bullet jacket material
Bullet diameter
Bullet length
Type of propellant
Mass of propellant
Dimensional accuracy of case (inside volume, case thickness, outside dimensions, etc.)
Consistency of case material (consistency of brass)
Type (Boxer, Berdan, etc.) and consistency of primer
Crimp pressure
Seating depth
“Squareness” of bullet in cartridge
Bullet muzzle energy (also depends on barrel)
Bullet muzzle velocity (also depends on barrel)
Cartridge temperature
Environmental Variables
Wind speeds between shooter and target
Directions of wind between shooter and target
Temperature
RH
Altitude / air pressure
Mirage
Amount of light
Human
Visual accuracy / discrimination of target
Visual accuracy / discrimination of scope reticle
Range estimation (distance to target)
Trigger control
Steadiness/ability not to flinch
Breathing
Heartbeat
Follow-through
Uphill / downhill compensation
Calculating the amount of bullet drop (trajectory) due to bullet muzzle velocity, ballistic coefficient, gravity, air density, wind, etc.
Calculating the amount of horizontal drift due to spin stabilization, wind, earth rotation, etc.
Now my head hurts.
In a nut shell, just about everything affects accuracy, to one degree or another. Long range shooting ain’t easy.
Thanks! That was an awesome explanation, and I’m clearer now on the parameters. I am curious about one note you mentioned re taking the “rotation fo the earth” into account. Was that a joke, because I can’t see how that’s going to need to be calculated as a factor to adjust for if the target, bullet, and the shooter are moving in the same physical inertial frame of reference re the speed of the earth’s rotation.
It isn’t a joke. The fire control systems for guns on warships have to take it into account.
mks57 is correct – no joke. We’ve known about it for over 100 years.
In 1886 the British Small Arms Committee discovered that the earth’s rotation can create a sideways drift effect and an over-range/under-range error, and that the magnitude of the effect was dependent on latitude and direction of projectile. In one of their tests, it was found that a projectile drifted 6" at 1000 yards entirely due to the earth’s rotation. This was in addition to spin gyroscopic drift.
Today the mathematics for modeling the effect is mature, though it is only used for missiles and long range artillery shells. Still, the effect is there at 1000 yards, and world-class 50-BMG shooter will take it into account when shooting at extreme ranges.
First let me make clear that I am not a world class rifle shot, not even close to it. I have a little experience in .22 benchrest competition which taught me a few things about rifle vs. shooter. I shot with a modest, $700 entry level rifle against guys shooting 30lb, micrometer aimed “rail guns” costing $4-5k or more. The funny thing is once I got the hang of reading wind flags and deflection I would consistently beat half these guys. The 100pt circle is half an inch and if any part of the bullet hole goes outside it’s only fifty. At fifty yards a tiny puff of wind would deflect a shot out of this circle. Some guys had digital weathervanes to tell them exact direction and velocity and charts that showed the deflection. I had a couple of tripods with a streamer of surveyor’s tape fluttering in the breeze. That is a tiny fraction of why Carlos Hathcock is a legend and a fool who has no skill but can afford an expensive rifle isn’t.
Crafter_Man:
First: Cool gun! I’d seen one and debated on whether or not to get it myself. My money situation wasn’t right, and my gun safe (medium-sized) is currently full, which would necessitate another expenditure on top of the rifle, so I passed.
Second: thanks for the John Ross link; I didn’t know he had a website. I’d looked a few years ago (not long after Unintended Consequences was published), but hadn’t checked again in the mean time. Since he’s a “homey,” I might be able to get my copy of his book autographed…
Not neccessarily so, at least in the real world with wind. As I saw in benchrest guns that are are a machine rest can be beaten by a pretty good shooter with a pretty good rifle.
Damn you guys. You have me ready to go down to Legendary Guns with my Discover card <hyperventilate> Calm down… I can resist getting the .50BMG they have on the counter but I just may look at the S&W P99 again. I picked up some supplies at Dillon Precision (I’m working at an office just two miles from there) so that mite sate me for a while. Still, 10lb of crushed walnut shells isn’t a new gun. I’m going to try and load a thousand rounds of .45 ACP by Wednesday. Sure would be nice to break in a new gun with it…
Say, do you guys know if the P99 has weird polygon rifling like Glocks so you can’t use lead bullets? I hate finicky guns that blow up with handloads.
John Ross is pretty easy to get a hold of. Just go to Knob Creek during one of the Machine Gun shoots that are held twice a year. The first time I was there he was manning the Kent Lomont table, helping Kent sell guns. That’s when I approached him and asked him to sign my copy of Unintended Consequences.
The second time I saw him at Knob Creek he almost ran over me with his white van. :dubious: