I also live in Gilbert Adora trails. I also compete in long range and mid range with my 90VLD. This year I set a record with in at the SWBN 600 yards 200-12X and took first in my class for Palma and 1000 yard agg the gun can shoot and the 90s did extremly well. I loaded all my ammo on a analytical scale and the vertical was awesome. I gave up points do to poor wind calls. I push them at 2820 with Varget.
What's the lowest SD you can get with 223?
- Thread starter ashiha
- Start date
Any chance that you measured the SD/ES of that load?
skiutah02
Silver $$ Contributor
Excellent shooting! Nice job. Drew
That load had a SD of
let me look at my data. I want to say it was in the ballpark of 8 or 12. I will double check.
Many thanks. Also, great shooting and congrats!
I'm constantly amazed at the amount of legendary shooters there are here.
Here's some data for you to chew on.
I chronographed 604 five-shot groups with my Howa 1500 .223 shooting mostly SMK 69gr with IMR 8208 XBR and got SDs from 2.22 to 123. Seven percent had SDs below 10. Some of these groups were shot with powder measured with the case activated powder dispenser and some were weighed. Some brass was casually prepared and included plenty of Lake City and Wolf.
With my Savage/Shilen .223 F/TR gun I chronographed 277 five-shot groups with SDs between 2.08 and 80. All charges were carefully weighed using a variety of powder, much of it Vihtavuori N-140, IMR 4198, and IMR 8208 XBR. Bullets were mostly moly coated Berger VLD 80gr or SMK moly coated 90gr. Fourteen percent of the groups had SDs better than 10. All the brass is Lapua carefully prepared
In comparison, my Savage/Shilen 6mm BR Norma shot 195 five-shot groups with SDs between 1.79 and 73, 30% of which had SDs better than 10. Powders were mostly CFE-223, IMR 4895, and IMR 8208 XBR and bullets were mostly Berger 105gr Hybrids, VLD Target, or VLD Hunting. All the brass is Lapua carefully prepared.
You can see that the 6BR gives much better SDs; I guess it's the nature of the beast. It's also easy to see that when I'm careful making .223 competition ammo, the SDs are much better, but still not nearly as good as the 6mm BR ammo. And making more casual ammo for a fun range gun, the SDs aren't as good.
However, and this is important, the SDs don't correlate very well with group size. Here is a plot of several thousand rounds showing both MOA and Group Height vs SD for my Howa 1500 .223 @ 100 yards. The trend line for MOA is nearly flat which means that even horrible SDs produce good MOA numbers and really small SDs can produce very bad MOA performance. Group height shows essentially the same thing.
SD vs Performance
Bottom Line: I strive for good SDs and low ESs. But this graph shows that I worry about it a LOT more than I should.
Is there a thread sharing your findings? This has to be one of the most complete data sets relating ES/SD and accuracy. I'm sure there is a lot more that could be derived from your data if you were willing to start a thread and share your info.
I don't mind at all. I just want information, lots of it.
skiutah02
Silver $$ Contributor
I've started annealing every firing. In my hands, consistent neck tension is one of the more important things for repeatable accuracy for the 90vld. And yes, this means having to turn necks. You may or may not have to but I decreased my group's size by about half with 0.001 more neck tension than I had been using. An additional 0.001 NT and the groups doubled (back to original ) Drew. Practically giving away the Coke formula.....
Thank you.
eric n
Silver $$ Contributor
Thanks Drew.
I've found more tension is better as well, along with ocd brass prep and batching.
I used to anneal every firing with the 80's but gave it an honest go without and found no difference on target after 3 firings. I did have to drop down a bushing size on the 3rd firing though to keep up with spring back.
Obviously, I'm not going to have the luxury of experimenting due to brass life, so back to annealing.
I sure hope Berger cranks these things out soon.
I've found more tension is better as well, along with ocd brass prep and batching.
I used to anneal every firing with the 80's but gave it an honest go without and found no difference on target after 3 firings. I did have to drop down a bushing size on the 3rd firing though to keep up with spring back.
Obviously, I'm not going to have the luxury of experimenting due to brass life, so back to annealing.
I sure hope Berger cranks these things out soon.
I just reviewed my extensive data sets from a 1 in 12" twist .223 and a 1 in 14" twist .222.
Standard deviations in the low teens and single digits are more common than not without neck turning or annealing. My standard brass prep is to clean in STM, ream the primer pocket, chamfer the case neck, and check and remove any burrs from the flash holes. Common powders are Varget, CFE 223, H4198, H4895 and Blue Dot.
Compared with the experiences of others with longer bullets and faster twist rates, I am inclined to think many of the challenges reducing standard deviations may be more related to the longer bearing surfaces and the faster twist rates. It may also be due to my cleaning procedures which others find excessive.
Would like to know if any of you fellas have dabbled with powerpro 2000 and the 90s.I just had a fella put a 223 together his load work up was 25gr in lapua brass with 90 smk and rem 7 1/2 primers avg. speed out of a 26'' McGowan is around 2785 and at a 100yds. it bugholes.I am dieing to get out to the range and stretch it to see if the vertical is going to hold up or if its going to be all over the place thanks.
I guess I didn't list in the other thread that I also use STM to clean. However, I have also heard that many benchrest shooters have opted not to remove all the carbon from cases. I don't know if that applies here or not. What I took from the concept was that when we clean with STM, the inside case necks are so squeaky clean that they tend to have additional grip that is less predictable. So I have been adding some imperial dry neck lube to try and counter that issue.
Could be. I've heard that the effect was due to cold welding. Most of the data I have over many years is in cases of shooting withing a few days of loading. Also lots of work with various coatings: MS2, WS2, HBN.
I really like the MR2000 in .308 but with 155 bullets. I wasn't as pleased with in on the heavier bullets.
I tried to shoot it in .223 but couldn't get enough in the case for magazine loaded ammo so gave up. I didn't try it with single load ammo.
Most accurate and fastest vel. powder that I've shot up to 80gr in a .223 was IMR 8208. I would look hard at it again if I were shooting 80gr or lower.
I tried to shoot it in .223 but couldn't get enough in the case for magazine loaded ammo so gave up. I didn't try it with single load ammo.
Most accurate and fastest vel. powder that I've shot up to 80gr in a .223 was IMR 8208. I would look hard at it again if I were shooting 80gr or lower.
BP1
It's not that I didn't like the powder, I just couldn't get enough in the .223 case for magazine loading 77gr bullets.
For .308 with a 155gr bullet, it's my top pick. 50.5gr in a Win case gives me 3210fps and I'm on my 8th reloading of that brass without any issues on the primer pockets. With 175's or 185's I could get the velocity higher than Varget but didn't have the accuracy when the velocity was higher or maybe, the accuracy wandered. Some days decent, some days not so good.
I think maybe it would be a viable option for the 80 or 90gr bullets if single loading and the throat is long enough to allow the bullet to be seated out where it isn't taking up powder space. I just couldn't get it there with the 77gr seated magazine length so quit that quest.
I was shooting mostly XTC at that time and wouldn't consider swapping to a different powder from what I shot up front to what I was shooting at 600yds.
It's not that I didn't like the powder, I just couldn't get enough in the .223 case for magazine loading 77gr bullets.
For .308 with a 155gr bullet, it's my top pick. 50.5gr in a Win case gives me 3210fps and I'm on my 8th reloading of that brass without any issues on the primer pockets. With 175's or 185's I could get the velocity higher than Varget but didn't have the accuracy when the velocity was higher or maybe, the accuracy wandered. Some days decent, some days not so good.
I think maybe it would be a viable option for the 80 or 90gr bullets if single loading and the throat is long enough to allow the bullet to be seated out where it isn't taking up powder space. I just couldn't get it there with the 77gr seated magazine length so quit that quest.
I was shooting mostly XTC at that time and wouldn't consider swapping to a different powder from what I shot up front to what I was shooting at 600yds.
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