In theory your groups should be 1.25" but that is rarely the case. Even if all outside factors are non-existent. It greatly depends on bullet stability, velocity, BC and many more key factors. If it was more than 1 MOA at 500 I would be suprised. Figure on 2-5" That is without any wind.
Get out there and try it.
Good shooting /ubbthreads/images/graemlins/smile.gif
As a regular benchrest competitor at 500 yard Grooundhog matches...the answer is "NO"....there are too many variables to ever make that logic work...my 6PPC will shoot .100's all day long at 100, but I've never gotten a sub 2 inch group at 500..and I've been doing this for 10 years and I've seen lots of groups at 500 yards from everything made on this planet and have "NEVER" seen one below onch inch..easy to talk about and B S about but very difficult to do...
It is possible, I have done it... less than an inch at 500. It wasn't luck and the rig shoots bugholes in good conditions. Testing for drop I fired a group at 300, 400 and 500 yards (3 shots) consecutively and groups were (at 300 I forget???) but about 1.1" at 400 and .980" at 500. The 300 yard was very small, smaller than the others I just forget but, it's on the pic I took of the targets some place.
I've shot several 2-3" groups at 800, and a nice 7 shot group at 600 once with the 200gr Accubond random load that measured under 2.5", one was a flyer 1" out to the right too, so really it was a 1.5" and a flier for the whole story and those were fired super fast before dark 30 just to compare the drop to the 210 JLK. This is with the 28 lb. bench rifle in 30/338 Lapua Imp.
500 yards is 5 times as far as 100 yards so group dispersion would be five times that of the 100 yard, or 1.25", in perfect conditions. Due to wind, velocity and other variables I factor in about a 5% increase in group size for every 100 yards beyond 100, 20% at 500 and 45% at 1000 seems reasonable and fits pretty well with my experience.
In a nut shell, I believe a rifle is capable at 500 yards to hold it's 100 yard level of precision, I've just seen it too much, but still figure on the 5% per 100 rule.
I have seen Brent's 30-338 LM imp rifle in action. It is a true performer.
Hey Brent, remember that load you shot that evening at over 3700 FPS??
I did one real similar last week. I shot a coated 180 Accubond 180 at 3709 /ubbthreads/images/graemlins/blush.gif out of that 300 RUM of mine.
I recently moved to Anchorage. We need to get together soon so I can get you your disk back. Also that program I gave you has been completly overhauled and sports a real ballistic calculator this time. I will get you a fresh copy. Much easier to use and alot more functional and of course dead accurate.
For the past ten years I've been involved with organized/competitive 500 yard shooting..at these matches I've gotten a chance to see thousands of "5" shot groups at 500 yards, from some of the best shooters on the planet, actual world record holder(s) at 1000 yards and have never seen a group smaller than 1 inch, in competition. I've seen some that were close, but never under an inch. The smallest was a 1.06 and lots in the 1.1??? but "NEVER" under..in competition. I've gotten a chance to see just about every caliber and configuration that has ever been dreamed up, from .17's to .338's amd everything in between with rifles built by the so-called best long and short range smiths in the business and still have never seen one under an inch. As I said, I'm sure I will someday, but as of last Saturday..I'm still lookin..easy to talk about and BS about but very very difficult to actually do..in competition, in front of 50-150 shooters and watchers.
Hey buddy, long time! I'll hook up with you some time, no sweat on the disk either. And thanks for the program, can't imagine you made it even better, but COOL! I'm over working in Nome again this season and won't be back for a while but, I'll look you up when I do get back to town. I'm living in North Peters Creek when I'm there.
That sounds about right out of you rifle. When I get back I'll have to play with the 180 AB and see if it flies as good as the 200's. I think that 178 A-Max is still the only light end bullet I've run through that rig yet. I think all I got out of it was about 3640 (3670??), heck I can't remember but I don't think I hit 3700 with "mine". I do remember the primer's crater! 3550 is about as high as I get with that load at safe pressure though.
Respectfully, I'm not a bullshitter but rather deal in factual data. I do however concede to having not shot those groups under the conditions you gentlemen might find in competition, as the conditions were of "my" choosing... kinda-sorta. Well, there were pretty good conditions when I chose to shoot that day and time I guess. The other fact, as I think I mentioned previosly, and I appologize if I failed to, but they were just three shot groups, not five... and we all know that the next two will make a difference too.
Come to think of it now, I shot an F-Class match with Michael last June I think it was, (which was the first and only match I've ever shot in BTW) and managed to shoot and X for a sighter, then 20 rounds for a score of 200 and 16 X's. The ones that were in the ten ring were practically on the 10/X line but were 10's not X's and 16 of them were inside the 10"? X ring so I figured that pretty good for 20 rounds in 30 minutes, still, far less than the precision I see with three shot groups at that distance!
Never intended to call you a BS er!! It's just that I get to hear tons of people tell me they can shoot 5 shot groups under an inch at 500 yards and all I tell them is.. Do You need directions to the match..it is very very very difficult to do on any day..5 shots, under an inch, center to center... Most people never get a chance to actually shoot off a bench rest out to 500 yards, especially here in the northeastern part of the USA...most actually never fire much above 100 yards with their deer rifles and most don't realize how difficult it actually is. Three shots groups are a totally different story, I was spotting for my buddy on Saturday and he had 3 shot's that almost touched at 500 yards with his .243 AI shooting 108 long range bullets..and for whatever reson the 4 shot hit about and inch and half from that little triangle and the 5 shot almost touched the 4th..we were both scratching our heads...As I said..I was not and never will doubt anything in the shooting world..sooner or later it usual gets done, but 5 shots under and inch at 500 is very very difficult to do, with anything...nothing personal..it's just that I'm sure you hear the same thing from lots of people about things that "THEY" can do...again nothing personal!
What bullet run do you fellows get? My neck runout is about .001 but my bullet run out is about.003.I just got a new bersin tool and it works great but i was wondering what i should get comparing the neck to the bullet runout.