Sierra .308 180gr Gamechanger - 300WM - RL26 - Holy Cow!

[Muddyboots]

Sierra 180 grain Gamechanger: G1 -0.515 @ 2100 fps and above 0.480 between 1680 and 2100 fps 0.445 @ 1680 fps and below
Rifle: G1 Sendero 300WM 26" no brake so clean 26" barrel
Since I cannot do a ladder at distance I wanted to at least get some velocities and shot at 25 yards chrono 18' from muzzle.
Boy was I shocked with what I found so far.

RL26 0.020 off lands
74.0 = 3003
74.5 = 3044
75.0 = 3086
75.5 = 3152
76.0 = 3174
76.5 = 3205
77.0 = 3228
77.5 = 3244
78.0 = 3259
78.5 = 3284
79.0 = 3292
79.5 = 3308 - very slight ejector marks, primer still has round edges, bolt lift no difference
Stopped at this point since my stop is to protect brass and few more extra fps is meaningless to me.

Checked chrono against known load and it was spot on.

So has anyone else used RL26 with this bullet with similar results? If snow clears out tomorrow, I plan on running a 5 shot 100 yard see what it does test. I ran it through RCBS external calculator and attached a 600 yard shot and data table for kicks. I used a 300 yard zero and it will drop 8.4 at 400 yards with having less than a 4" +- to 300 so point and shoot to 300 on most animals to 300 is pretty interesting. Granted this is all conjecture at this time but what else do I have to do right now?

 

[Jud96]

I did a lot of testing with the .300 Win Mag barrel I had. I used IMR 4831 and IMR 7828, because RL26 wasn't out then. I tried everything from 175-208gr. I was able to get 175s up to 3200ish without pressure with IMR 4831, and got 190s around 3100fps. That's impressive to see you getting that speed with 180s and RL26. I know I used completely different powder and bullets than what you're shooting, but it still shows the .300 WM can be very potent. It seems like the .300 Win Mag always seems to be underloaded with 180-190s.

 

[Muddyboots]

Just confirmed that 78.0 grain with the 180GC was still 3260's with 5 shot 100 yard test. Shot just under MOA and I haven't begun seating depth or even some load changes to work on group size. But a 180 at 3260 under MOA is still nice hunting load anywhere. The group was shot off an old wooden table in 20 mph winds so I guess worse case scenario!

 

[cape cove]

Had the same *** moment with RL-26 and the 175 Barnes LRX. Worked up to a max load in my rifle(76.6grs) and got 3225 ft/sec from a 24" barrel and safe pressure. Had to check the chrono with my 22lr to be sure. Accuracy with this load was .75 MOA

 

[cape cove]

Jus checked your #'s again and amazed at how close they match mine, grain for grain although 2" less barrel. Only diff I had to stop at 76.5 as I felt this was max.

 

[Muddyboots]

RL26 is probably maxing out and the extra 2" for it may not add anything else. But good to see common numbers.