175 smk 308 velocity

[Rh0dz]

Novice reloader here. I did a OCW test this weekend with my 308 in a 16" barrel. Overall very pleased with the 175 smk results with varget.

Is 2400 ft/s too slow? Groups 2,3 and 4 look great for a gas gun, but slow. Would you focus on group 8 around 2500 ft/s and ES of 10 (tiny sample set but still nice).

Tia

 

[Dogtown]

Out of a 16" gas gun, 2400-2500fps is kind of the normal. Yes, you can run a bit hotter but it's often not worth it because you can tear up your brass and sometimes the most consistent loads aren't the fastest.

Someone else can analyze your groups...

 

[Doom]

To give you some perspective, my 20" bolt gun runs about 2520 with the 168 gr. Pushing 2500 in a 16" gas gun is going to waste brass and will probably beat the action up pretty good unless you have an adjustable gas block.

I would pick 1,2 and 3. By the way 42 gr of Varget/IMR 4064 is a known node.

 

[Rh0dz]

To give you some perspective, my 20" bolt gun runs about 2520 with the 168 gr. Pushing 2500 in a 16" gas gun is going to waste brass and will probably beat the action up pretty good unless you have an adjustable gas block.

I would pick 1,2 and 3. By the way 42 gr of Target/IMR 4064 is a known node.

The feedback I was looking for. Thank you.

 

[diggler1833]

Concur with the above man. Go with what your rifle likes. 2,400 will get you out a little ways.

41.8 (41.75) was the IMR-4064 charge weight for Federal GMM with the 175gr SMK. Not sure if that is still the case or not.

My M24R runs 42.6 - 42.8gr of Varget best. 42.7 gives me 2,575 FPS on a 24" barrel for comparison.

 

[whatsupdoc]

20" AI using 308 FGMM 168 Factory Load 2558 FPS
20" AI using Creedmor Sports factory load 175gr Lapua Bullet 2566 FPS

2400- 2430 FPS for a 16" is about right.