Well, I finally got to the range with the new BDay rifle. I must say I am very happy with the rifle, only medium happy with the ammunition. It seems I have gotten spoiled with handloading my other rifle. While I handload the other one mainly for costs savings, it seems I've become a bit of a velocity consistency snob, lol.
The one I was shooting mainly today is the top one, mentioned in my previous post. For refresher, it is a Sako model 85 in .22-250 caliber.
This was a terrible day for attempting benchrest accuracy. First, I was upset because the long distance 100-600 yard range area was closed for upgrades that were supposed to have been completed last month. I had planned on shooting at 200 and 500 yards today for testing. Luckily, I was able to at least go to one of the several other 100 yard ranges.
It was cold, winds very gusty at 6-12 mph and even trying to spit a little snow now and again. I almost didn't go, but I bundled up with my long underwear, flannel lined jeans, sweatshirt, coat, gloves, etc. and braved it. I've been waiting to get this to the range for weeks now and nothing but a downpour or blizzard was going to stop me. Have I made enough excuses for the groupings yet? Haha, actually, these are very good groups for me and I am very happy with that, despite the conditions and excuses, I'm lucky to do this well on even a good day.
Not only did I get two - 5 shot groups in a row to shoot under an inch, there was a third not pictured here with another 4 shot group under an inch with only my first shot about 2 inches high until I adjusted the scope for this range.
I had two goals for today, first, to gather some velocity info using the labradar chronograph, and second to see how well this would shoot at 100 yards my first time out and how much scope adjustment is needed (if any).
Using my Strelok ballistics calculator, it determined that with a 50 yard zero (which I did at home last week), I should be shooting at about "2 clicks" down at 100 yards, and be exactly on zero again at 200 yards. I felt this was a good general setting for this caliber and rifle. Here was my 50 yard target from sighting in earlier in the week.
(Note those are half-inch squares compared to the one-inch squares at 100 yards.)
What I found out by using the LabRadar chronograph, was that even though these bullets were rated at 4,000 fps (feet per second) velocity, the factory tests them in 26" barrel rifle. My rifle barrel is only 20 inches long, which means that they actually go quite a bit slower, around 3,860 fps. This meant that my first shot at 100 yards was over an inch or so high. I adjusted down 4 clicks, instead of the recommended 2 clicks and was then right on the money. Now, I have more accurate velocity data to feed into the Strelok ballistics app for longer range shots without wasting ammo.
In my long range rifle, a .338 Lapua Magnum, I typically handload the ammo to save cost. When doing that, I hand weigh the amount of gunpowder in each load to ensure consist velocities, as that will be more accurate at longer ranges. I guess I have gotten spoiled with that. It's been probably a decade since I bothered testing any factory ammunition. Well since this is to become my new favorite medium range (100-600 yard) gun, I wanted to get accurate readings to extend the distance and just to see how consistent it is.
I was very disappointed in the ammo. Even though these are high velocity specialty ammo, designed mainly for coyote and varmit hunting, not match grade target ammo.
I'm shooting Hornady Superformance Varmit, 50 grains in Sako 85 S .22-250. This ammo is rated at 4,000 fps. I'm getting an average around 3,860 fps out of this Sako with a 20" Barrel. About what I expected.
But the real question is it seems to vary extremely widely. It shoots decent at 100 yards (pic on a windy / cold day). I can't imagine how this could shoot consistent at longer ranges.
I shot 3 - 5 shot strings through a LabRadar chrony with these results
String 1: Avg Vel=3849 fps; Max=3896 fps; Low=3795; Ext Spread=101.63 fps; Std Dev=36.77 fps
String 2: Avg Vel=3855 fps; Max=3901 fps; Low=3810; Ext Spread=91.7 fps; Std Dev=43.31 fps
String 3: Avg Vel=3875 fps; Max=3904 fps; Low=3837; Ext Spread=67.06 fps; Std Dev=27.75 fps
For those not familar, the important ones are the Extreme Spread, and Standard Deviation. This tells us how consistent the loads are. The smaller those numbers, the better. I typically get in the low teens for Std Dev in my handloads or better, and only around 8-20 or so Extreme spread (The maximum difference between rounds).
I wasn't expecting the factory loads to be as consistent as my meticulously weighed handloads (I measure to within 1/10th of a grain, which is smaller than a sharp pencil tip). I was expecting maybe 20-50 fps max difference in factory loads, certainly not 100 fps! Wow, in my eyes, that's not much quality control. Perhaps I've grown too compulsive in my pursuit of "the perfect bullet".
I do love the trigger on this rifle. As I described in more detail in my earlier post a couple weeks ago, it has both an adjustable trigger (which I adjusted down to 2.5 lbs. and what is called a single set trigger. This set trigger allows me to push the trigger forward, which "sets" it, and then lowers the pull to only 6 ounces. Yes, that's less than half a pound. Even in today's horrible weather, I found that I really, really, like this set trigger for bench rest shooting. I can't wait to get it out to longer ranges.
I don't have the dies and powder to handload these yet, but after seeing this, I will definitely need to start!
I must say I am tickled with the rifle, and now just need to tune the ammo to match. This is one of the things I enjoy most, the science of tweaking and twiddling to get it just right. If it were perfect out of the box, I would be more disappointed at not having the challenge!