Browning X-Bolt Speed – Nosler 168g ABLR w/ IMR 4831 Groups – Updated 2/2/23

As you may know, I have been working up hand-loads for my moose hunt and finding the Nosler 168g ABLR reaching over 3000 fps with IMR 4831. But the question is, with what accuracy or groups?

Well, I shot this group below and it looks like a tight 3/4″ except for the flyer. I shot the third shot in the upper right target and extrapolated its position on the string below. Why I shot that upper right target? Because I wanted a smaller target as a focal aim point.

But it needed to be repeated in the second target below for me to validate it. The trigger is a heavy 4 lbs. but I was able to get used to where it breaks. The thin mountain barrel does heat fast and after 3 shots to warm it, it begins to string. 

I repeated the same shots a week later with all the same components at 100 yards. The first 3 shots group 3/4 ” from a cold barrel and the 4th shot drops an inch. I know that a lighter trigger may also help. But overall, I was very pleased with the cold shots for hunting purposes.

Tests continue Using my Labradar

I loaded some 168g ABLR’s with hot H1000 Powder to compete with the IMR 4831. See below low left and right 100 yd 3 shot cold barrel groups with extreme spread of 78 fps an 2 inch groups. The IMR 4831 wins!

I did shoot 168 ABLR today for a third bench rest group for the IMR 4831 and Statistics. Below this group was 1 1/4 inches. Shown below with associated Labradar Stats with Extreme Spread of 14.34 fps and a Std Deviation of 8.17. Very nice indeed!

Labradar Report for IMR 4831

Device ID LBR-0028541                                      
                                                             
Series No 4                                             
Total number of shots 3                                 
                                                             
Units velocity fps                                         
Units distances yd                                         
Units kinetic energy ft-lbf                                
Units weight grain (gr)                                    
                                                             
Stats – Average 2937.25 fps                                 
Stats – Highest 2946.69 fps                                 
Stats – Lowest 2932.35 fps                                  
Stats – Ext. Spread 14.34 fps                               
Stats – Std. Dev 8.17 fps                                   
Shot ID V0 V25 V25 V50 V75 V101 Ke0 Ke25 Ke25 Ke50 Ke75 Ke101 Proj. Weight Date Time
1 2933 2893 2893 2852 2814 0 3207 3120 3120 3034 2953 168 2/2/2023 13:01:22
2 2932 2882 2882 2841 2801 0 3207 3098 3098 3011 2925 168 2/2/2023 13:02:44
3 2947 2907 2907 2868 2829 2788 3238 3151 3151 3067 2984 168 2/2/2023 13:04:08

 

Interestingly, I did note that a drop in outside temperature affects ignition and velocity. Last week I shot at 37degrees F and MV avg was 3003. Today at 26 degrees F,  MV avg was 2937 a drop of 70 fps. At 600 yards that equates to a drop of 4 inches on a moose. I’ll keep that in mind!

More Soon…

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This entry was posted in Big Game Hunting, Bullet Tests and Reviews., Cartridge Reloading for Long Range Hunting, Chronographs and Radar, Uncategorized by Ed Hale. Bookmark the permalink.

About Ed Hale

I am an avid hunter with rifle and Bow and have been hunting for more than 50 years. I have taken big game such as whitetail deer, red deer, elk, moose, buffalo, Russian boar and African Plains game such as Kudu, Gemsbok, Springbok, Blesbok, and Impala and wrote an ebook entitled African Safari -Rifle and Bow and Arrow on how to prepare for a first safari. Ed is a serious cartridge reloader and ballistics student. He has earned two degrees in science and has written hundreds of outdoor article on hunting with both bow and rifle. He lives in New Hampshire with his wife Susan. He is a Patriot Life Member of the NRA.