Hang on Green Tips - we are talking about two different things. I am only testing my rifle's slow fire accuracy potential and that's it. The procedure for measuring it's merit as a battle rifle will be completely different. I would defer to guys like you and TV for that, and there are any number of other guys that can also do a better job than I can. I like this rifle because it will fit in a ATV box, and I can take it out for plinking in the woods, potting coyotes close in, and it makes a cool toy for the range. My needs are very different from those of the squaddie or the runnin' gunner.
My data is as representative as I can make it: my rifle is un-modified, straight off the rack as it comes from the factory and there is no reason to believe it is that much different than any other - the QA/QC controls are probably a matter of public record. I doubt you will see manufacturing tolerances vary with these guns the way you would with a chicom SKS, for example. There will be statistical variances in production but I will accept that here just as I would for any magazine writer doing a similiar rifle accuracy evaluation. My bench set up is a tad sloppy...I need some better sandbags and as a shooter I need more trigger time - but I listed that caveat already. Temp was right around zero and winds were light...and as far as my reloads - I seat them out as far as I can and still fit in a mag. My speeds came off a cheap garden variety chrony but even the cool kids are getting their velocity data from them. I like to see my velocities in around 2700~2800 FPS which is where the match shooters like to be. I would prefer a full blown ballistics lab - but whaddya gonna do? My testing is, of course, preliminary. I would say the biggest contributor to error in my set up was me as the shooter. You younger guys with sharper eyes would probably done a bit better.
The 'heavier bullets for faster twist rates' is actually a valid rule of thumb. My experience runs counter to yours; my AR and SL8 had the 1:7 twists and they both disliked the 55 grainers. But you are correct in that they may shoot well in some rifles with fast twists - I will eventually try them in the Tavor but I am starting out with the longer bullets first. I will also be using boat tails and match bullets first too - again, as a rule of thumb, they tend to shoot the most accurately. If I were on a limited budget with limited time I would start my load development with the stuff that tends to produce the best results.
As my good buddy Forrest likes to say, life is like a bowl of chocolates and so are guns.
Sorry, The rule of thumb is that every barrel is different, what works in one may or may not work in another even if it is the rifle that followed the last one out of the factory.
Your theory of fast twists for heavy bullets is only true to a certain extent. A fast twist is needed to stabilize LONGER bullets which are typically heavier but you can not over stabilize a bullet. You can however spin a bullet faster than it was designed which can cause it to come apart when it leaves the muzzle which may limit you from using some light varmint bullets in a fast twist barrel.
Here are some examples taken from my experience.
My first SL8-4 (one of the first ones that came into Canada) loved 75gr Black Hills Match BTHP and would shoot 1moa all day as fast as I could squeeze off another round after getting back on target. My new SL8-4 shoots the same ammo into about 3moa.
My current SL8-4 (1:7 twist of course) will shoot Winchester 50gr Ballistic Silvertips into just a hair over 1moa which is about the same as it does with Hornady 55gr V-max. It will also shoot my 60gr Nosler handloads into sub moa.
So, while tight twists are needed for longer (heavier) bullets that doesn't mean they won't shoot shorter (lighter) bullets. Every person on here needs to experiment and find a round that THEIR barrel likes and do their own load development with their handloads. I will gladly share my handload recipes but I always warn that they may not work well in someone else's rifle.
Once someone finds the round their barrel likes they have to look at the cost of that ammo and decide if it is worth it. As has been said, some guys have found that the best ammo for their rifle costs $35/box and others have been lucky and found that their rifle likes Norinco garbage.
Those are the biggest reasons I handload. I get to pick my bullets and tailor them to work with my rifles. When I am finished I get premium ammo that costs about the same as the cheapest factory loads.
I also don't do any work on the chrony until I find my accuracy nodes then I check them for velocity to record the data for comparison. Velocity has very little to do with accuracy other than every barrel will have a certain velocity for a certain bullet weight where the bullet leaves the muzzle at the same point in the harmonic whip which will be the velocity where the point of impact is the most consistent.
And GT's right, if it had a quality barrel it shouldn't matter how fast you shoot. My SL8-4 doesn't get babied when I'm doing development, I shoot, get back on target, stabilize, and shoot again. This crap about letting the rifle cool is only finding a way around having a sh!t barrel. My AR's get shot the same way and the accuracy doesn't change as the barrel gets warm. I don't let my barrels get so hot that I can't put my hand on them but they sure don't get a 5 min break between shots.
The biggest factor with any rifle's accuracy is the shooter, if you aren't shooting from a solid stable rest you shouldn't be posting on here saying what the RIFLE can do, you should be posting saying what YOU can do. If you're going to shoot using your skeleton for support just have fun out there and don't worry about tight groups, there are very few people in the world capable of shooting consistently that way. A bi-pod is better but bags or a solid shooting rest are the best. You need to take your body out of the equation as much as possible for the ultimate test of what the rifle is capable of shooting.
