600 yard advice?

[M14Robert]

My RRA upper doesn't seem to like SMK 80s that well. It barely holds the 10 ring on a reduced target at 100 yards so I didn't use it for the 600 yard comp at Hampden.
My upper likes the 77s (at least close-in) and shoots them at 1/2 MOA (for sure at 100 anyway). I shot them at 600 shooting 184 3x and 187 5x.
Would it be adviseable to continue using the 77s at 600 because the "potential" is better (close-range MOA) or should I shoot the 80s because of Zedikers claim that 80s "tighten" up past close range?
I found a combo using a different powder that slightly improved the close range accuracy of the 80s but then did poorly with the 77s. I'd like to keep the same powder for 77s and 80s if possible unless someone else has a different idea. I've always been told (and Pat sort of reinforced the idea) that you should keep the same bullet mfr and same powder mfr so that you don't get problems with fouling characteristics i.e. don't use Hornady bullets and IMR powder with say short loads, and then Sierra bullets and Hodgdon powders for long loads.
What say you gurus???
Maybe I'll try Hornady 75 BTHPs for short range and Hornady 75 A-max for long and see if they shoot better than the Sierras???

 

[Admin]

If you haven't shot the 80's at 600 yards yet, I would at least try it once to see what kind of results you are getting.

Brian any suggestions?

 

[bpm990d]

I'm out of the door right now, but will get back to you when I come home at 7:30.

B

 

[rscalzo]

I used the Sierra 80 grain in my RRA DCM using 24.5 of Varget. Decent results. I'm going to try out the 77 grain loads using the same powder and charge lext week in Reading. I'm hoping for the best..

 

[Dan S]

What powders are you using? Varget or Reloader 15 both work well in my AR, I aso use Remingto 7 1/2 primers
Give both the 80 Sierra's and the 75 Amax a try at 600. Not all bullets shoot small up close, especially the heavy (for caliber) bullets.

 

[Big Daddy 45acp]

A lot of the heavier bullets don't even begin to stabiize and settle down until they are past the 200 yd mark.

 

[bpm990d]

Honestly I think it should shoot a little better than 10 ring at 100yds. What are you using for a load with the 77s & 80s and how much are you jumping them?

I haven’t shot my stuff at 100yds in a long time so I don’t have a good reference as to how well they perform at that distance but at the end of the day it is how well it shoots at 600yds that will determine if it is any good.

Really good scores at 600 have been shot with 77s and even 69s, but the thing to do is to get the 80s or its equivalent or better shooting in your gun. The 600yd line is the most demanding stage from the standpoint of accuracy and your 600yd loads should shoot well and you shouldn’t have to shoot bullets that don’t perform well in the wind at that distance.

Also what twist is the rifle barrel?

B

 

[bpm990d]

Also on the powder thing, I think there is something to using the same powder and I have over the years slowly moved towards this and am using R15 for everything now. However I have shot some smoking scores by doing stuff like shooting W748 on the short course and then following it up with R15.

I shot 69s at 200 with W748. 75 Hornady HPBT at 300 and 80 Sierras & JLKs at 600 with R15.

When I was shooting the AR10 I shot R15 on the short course and Varget at 600yds and that gun was a hammer at 600yds. I shot several cleans that year and had many strings with more than 10Xs at 600yds.


B

 

[HPMainiac]

Robert
Try the Hornady AMAX 75's at 600, along with the 75 gr BTHP at 200 and 300 yards. Use the same powder with both bullets. H4895, RE15 and Varget are all excellent powders.
The 80 Sierras should shoot well too. 100 yards isn't really a good test of how they'll shoot at 600. My 600 yard loads don't shoot all that great at 200, but shoot better than I can at 600. Its good advice to try the 80s at 600 yards before giving up on them.
Dave Dow

 

[M14Robert]

Thanks guys. I was using RL15 with Sierra load recommendations and IMR4895 to IMR's recommendations. Jump I have tried with the 80s have been 5 and 10 thou off the lands and kissing the lands. Kissing the lands shot the best but I wasn't comfortable doing that. Twist on my upper is 1/8.
Thanks for all the replies and suggestions. I have some A-max on hand and just need to see if Bennett's has some BTHP so I can load dev with them side by each.
Thanks again!

 

[Jose]

I had a terrible time this year with Hornady 75 Amax bullets at 600. I was jumping them .01" and using 24.7 gr of Reloder 15.

I switched to Berger 80 VLDs jammed .020" into the lands and backed off to 24.5 gr. My 600 yd scores went up dramatically and I am averaging 193 - 194.

 

[bpm990d]

Jose,

The problem with trying to keep them within .001 of the rifling is that the ogive varies enough to cause some of the bullets to experience more pressure than others. They had a similar problem in the 92 Palma. They got a lot of elevation shots with guys that tried to chamber their rifles so the ammo was just touching. In my experience it is better to jump them at least .010 or to jam them good. VLDs and some of the Hornady bullets are a little trickier to find the sweet spot. I use to jam my JLKs good and they shot great.

Glad you found a load that worked. It's nice to have confidence in your ammo huh?

B

 

[Jose]

Brian, it sure is great to step on the line knowing your shots will be on call. It got so bad earlier this season that I hung up my service rifle and dragged my Model 70 out for the month before Perry and Perry.

The thing was that I knew at 300 yards I could hammer with 75 BTHPs, but the Amax were all over the place. That there told me I was capable of shooting well and something else was amiss.

The first time I tried the Bergers it was XTC at 300 on the MR-31. I shot a personal best of 198-11X and I was sold on that load right then and there.

BTW, I think you misread my Hornady jump. I was jumping them .01" (aka .010"), not .001". I understand the impossibility of assuring consistency that close to the lands. Agree that you either jam them in or get them far away.

 

[bpm990d]

Those friggin decimal points keep screwing me. Good thing I’m not an engineer, the bridge would fall down.

I remember that post you made over on NM.US about the change. I've shot some Bergers but not in .22, only .308. I want to get some to try but most likely 90s. I want to get a 6.5 tube when I rebarrel.

198-11 is a nice score. That little target is a bugger to shoot. Was that with a service rifle?

I have shot a lot of Hornady bullets, but tried the 75 A-maxes and got ho hum scores with them. It was only 100 of them, and they were the original ones. I'm gonna get some more to play around with at some point. The HPBTs were great and always had good groups with them at 300. I also shot a fair number of 6.5mm 140 Gr. A-max bullets and they shot great.

B

 

[Jose]

198-11 is a nice score. That little target is a bugger to shoot. Was that with a service rifle? B

Yep.

ETA: I think I'm going to try a box of 6.5 mm Berger 140 VLDs in my 260 Rem M70. At this point they are actually cheaper than the Lapua 139s that I use for 600.

 

[Jose]

I have 44 rounds left still loaded with the 75 Amax. I pulled the bullets and reseated them to jam .01" in. One of these weekends I'll give it a try and see how they work jammed. If they shoot better, I'll load up the last two boxes of Amax that I have and burn them up. But even after that, I'm still going Berger 100% for my 600 yd AR15 load.

 

[PatMcD]

I've always been told (and Pat sort of reinforced the idea) that you should keep the same bullet mfr and same powder mfr so that you don't get problems with fouling characteristics i.e. don't use Hornady bullets and IMR powder with say short loads, and then Sierra bullets and Hodgdon powders for long loads.
What say you gurus???

Rob, I'm bad at getting my point accross, sometimes. I don't think there is any big problem with shooting different powders or bullet brands at the short or long lines i.e. fouling.
I use one powder (RE15) because I am incredibly lazy. I was told to use 24.5 gr of RE15 with 80's. I did, and it shot well. I figured "why not try the same thing with 77's?". I did, and it also shot well. That is the extent of my load testing. I never tried bumping it or reducing it a 1/2 grain or use other powders. I did all this for my spacegun upper. When I switched over to the SR upper this year, I just used the same loads again. Like I said, I'm lazy.

As for your loads at 600, there really is no shortcut to going out and shooting them at that distance. A so-so 80's load at 100 might shoot better at 600, but I doubt it. With all things being equal, I would opt for group size over BC gain. Also, as I've said before, I need to load test with a scope. I just can't hold tight enough to get good feedback when I shoot them slung-up prone.