The National Record for 1,000 yard, Bench Rest Score and Group is a 100 (10x10) score with a 10 shot group measuring 2.81 inches or around 1/4 MOA. There are smaller groups shot with 3 or 5 shots, but just getting off 10 rounds at 1,000 yards, means that the wind can change not only multiple times, but at multiple yardages with varied temperature and humidity during the firing. With a muzzle velocity of just under 3,000 FPS, it takes 1 1/2 seconds to get to the target. Fun to pull the trigger and actually watch your round hit the berm 1,040 yards away after passing through the target. A lot can happen in that second and a half.
At 100 yards there is less time for things to effect the projectile and for score, short range Benchrest is shot with one shot put into each of 25 individual targets as some many shooters can put rounds through the exact same hole without being able to tell that there was more than one (or a totally pulled miss) - i.e. 0 MOA accuracy.
As you know, shooting precision at any distance requires a consistency in Shooter, Ammo along with quality equipment, the right cartridge and the ability to read and react to the existing conditions. Certainly easier to shoot a tight group on a windless day, then one with 10 knot winds. So there are only a couple things that we can easily control.
The Equipment - Rifle (action, barrel, trigger and stock), the optics and their set up and the bench equipment.
What Caliber / Cartridge - a 6PPC is the King of short range, but falls way off over 200 yards. 6mmBR is usually best for 300 to 600 yards, but at 1,000 the heavier bullets will better ballistic coeffcients take the lead.
The consistency of the finished loaded rounds.
Great manufacturers and great gunsmiths can turn out the gun. Great component manufacturers can turn out the ammo components, but now they need to be put together so that the shooter now has the equipment to provide the best performance, while it is up to the shooter to gain the skill, but the luck of the draw on the conditions on the day of any shoot or hunt.
I will be happy to start a thread dedicated to how I go about building 20 match bench rest rounds if you or anyone else care to see it. Some of the procedures may not add much in accuracy, but certainly can not hurt.
So a couple of other comments. Lets take the 30 BR compared to the .308 since you have one. It has become well known that small rifle primers provide more uniform ignition than large rifle primers, So the BR cartridges use small rifle primers and for 800 yard or longer F Class, most .308 shooters use the .308 Palma, difference over .308 Winchester, yep, small rifle primer cup. And why is a 30 BR (short .308 Palma) more accurate than a .308? Well you need to fill the case with powder when reaching an accuracy node. Why, think of an under filled case, depending how you handle it will result in how uniform the powder is laid out in the case and how uniform the ignition and burn will be.
My F class rifle is a .308, but I use Lapua Palma Brass and CCI 450 magnum small rifle primers over powders that fill the case.
Bench rest shooters measure powder to .02 grains, including cutting individual granules / flakes etc. and using tweezers to weight them on a scale accurate to .02 grains rather than a tenth of a grain. Both a Gempro as well as a FX 120i are capable to do that, though it will take a lot of effort in a $150 Gempro, but much less in a $650 FX 120i.
So I will start another threat on reloading for precision shooting. Let me know if I should keep it going.
But most important - Where a hat, or your bald spot will show!
Last edited by rkittine
on Wed Jul 27, 2016 3:47 pm, edited 1 time in total.
Sag Harbor and Manhattan, New York