Range Report Ballistic comparisons...

[base]

I have a 308 and my first load was a 168 SMK over 42.5gr Varget at a velocity of 2768fps. I was having problems with inconsistent hits at 895yds. A lot of people recommended a heavier bullet so I went with the 178gr Amax. I have a load worked up for the Amax on top of 42gr Varget at 2595fps. When I ran these 2 loads thru a calculator it showed at 900yds the SMK has 285.49"s of drop and 86.62"s of drift in a 10mph wind. The Amax has 306.53"s of drop and 88.45"s of drift. i would really like to use the Amax load as I may hunt with it if i can draw a tag. Should i stick with the SMK load or is the ballistics of the Amax still considered good and go with it. I hope what i'm trying to ask is clear. Thanks

 

[KYpatriot]

Re: Ballistic comparisons...

Check the velocity of the amax at 900 yards...that will tell the tale. If I were you would stick with the amax. The 168smk is good inside 800 yds or so depending on conditions, but it does not do transsonic as well as the 175 SMK. So stick with the amax or buy 175smks. For hunting I like the amax better then the SMK, I have personally seen smks pencil through game like an fmj, others have been successful with them and the subject comes up often. I mostly use accubonds for hunting. In my experience they work better than either, are as accurate as the others, and more reliable for biggame.

 

[roggom]

Re: Ballistic comparisons...

If you are looking to settle with one load and one bullet, then you can load up the 178. Past 600 for target and 400-500 max for hunting. Depending on altitude, you want to keep your max distance to were your bullet is still clocking 2000 or so fps.

Also not sure of the length of your bbl, but with 42 and 42.5 your velocities seem a tad high. Either way, try the G7 calculator. http://www.gseven.com/ballistic-program

This program is top notch, you dial in your numbers, then go out and validate your drops, re-enter and it corrects itself and outputs a true drop chart.

Good instructions can be had at Vortex. http://www.vortexoptics.com/content/lrbc_tutorials

 

[JC Steel]

Re: Ballistic comparisons...

Alot of people are loving the 175 SMK bullets for the 308. My gun for one loves them and shoots them very well out to 1000 yards.

 

[base]

Re: Ballistic comparisons...

My barrel is 26", also very smooth after fire lapping says a gunsmith who bore scoped it. I was using a chrono to work up loads from 41.7gr to 42.6gr in .3gr increments. With the .3gr increments the velocity difference seemed right between loads. Was using the Competition Electronics ProChrono Digital which seems to be good. Also after using my own chrono to test my 168gr SMK over 42.5gr of Varget i chrono'd and average of 2615fps. Which makes more sense between the two loads.

Would the 178gr Amax constitute the G7 drag model? The Ballistics FTE program, which is one of two i use, has several G models to choose from.

I was gonna try the 175gr SMKs since the 168gr SMKs worked so well but wanted a bullet i could also use to hunt with. The Amax came highly suggested compared to the SMKs.