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Discussion Starter #21
Holidays and hunting season took a toll on shooting time, but I'm pleased to say that I finished tweaking a 95gr SMK load today with 3 / 5 shot groups averaging 2in at 300yds. Now to load up 100 and go confirm drops to 1300yds.

This is a fun round. I'm going to stick with the AR version and build a 6mm bolt gun.
 

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what was your load specifics, barrel length, and muzzle velocity?
 

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Discussion Starter #23
Sorry, but life has gotten in the way of my shooting. I'll be going out this weekend to see if I can get some more data.

For now the I can give you the barrel and load specs:

6.8 twist 22" barrel. No marking on the barrel other than cartridge. No idea who made it.
FC Brass trimmed to 1.580
CCI BR - 4
Alliant RL17 26.8gr (seriously compressed)
95gr SMK
2.335 COAL
ASC Metal Mag with end plate cut out

Going to try out 80gr Nosler CC, 73gr Hornady ELD M, Berger 82gr BT Target and Berger 90gr VLD also.

I looked at switching to RL15, but everything I have read suggests it is not temp stable at all. I am going to see what Benchmark can do when I switch to the lighter projectiles. QuickLoad shows that I can get 2850fps with around 58k PSI from the 80gr CC.

Much more to come.
 

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Discussion Starter #24
So, here's a couple pictures of the ladder I shot at 300yds to find a node with 95gr and RL-17.

Settled on 26.8gr @ 2.335 COAL

I have 25 rounds loaded to go test. Just need the weather to cooperate now.



20200521_121540.jpg
20200521_121504.jpg
 

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Discussion Starter #25
Well, I shot the 25 I had loaded..... They did not do so hot. Going to retest the 25.6 - 26.2 range again and see if I can find a node in there. Should have more results by the end of this coming weekend.

I did commission a bolt rifle build.

R 700 SA
26' Hart (Fluted 7 twist)

Looking to get the 80 up in the 3000fps range and see if I cant make a 1000yd plinker.
 

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I've been to the 1000 yard range twice this last month. I'm learning long range is all about the smallest muzzle velocity standard deviation (SD) you can get. That is more important than group size at 100 yards. Both times, the 95 SMK with W760 had the best groups at 1000 yards. I'm only achieving a 0.545 BC (G1) in my 1:6.5 twist but I'll take the slower speed and smaller group size any day. 88 ELD-Ms are achieving their advertised BC and grouping a bit wider but better now that I switched to W760 from R17. R17 was giving me more velocity but larger SD. Berger 85.5 Hybrids with 2000MR have been grouping the best inside 300 yards but they come in last at 1000 yards plus the BC is coming in at 0.500 (G1). It's not worth the faster MV. They are getting pushed by the wind more and open up more in vertical spread even with a lower SD.

I've just started shooting with a mil-rad Vortex PST Gen 2 which has been a noticeable benefit. I've done MOA all my life but decided to get mil-rad just to learn about it. I but my MOA scope back on a second Valkyrie I've been playing with (1:7.7 twist) and I couldn't make the transition back to MOA. Mil-rad is just much simplier for me.
 

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Discussion Starter #27
I'm very interested in what your groups at 1000 have looked like. I am finding that I get really good groups around 3-400, from ammo that was not impressive at all at 100. Haven't moved into testing velocity because I use a magneto speed and it throws off groups. Probably time to get the setup to mount the magneto without touching the barrel.
 

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you will need your magneto to measure muzzle velocity SD. Here are the groups I've been getting at 1000 yards.

60943
 
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