realistic velocities? .308 / RE-15 / 190gr SMKs

[CavTrooper76]

Whattya suppose the realistic velocities would be using this combo? The Sierra manual has the max load at 40.4gr of RE-15. However my limited experience has the listed max loads in the Sierra manual very conservative. I might want to try running a little hotter with than the load Im using now which is 39.2gr which Im estimating at a around 2425fps, not chronoed but based on published loads, I just guessing really.

Anyone use a program like quickload that might be willing to run some numbers for me?

Thanks!

 

[freelunch]

Tough to answer without specifying a barrel length!

From Quickload for 190 SMK with Reloder 15 at OAL of 2.820". At 60,000psi chamber pressure (max is 60,191psi). Max loads. Brass H2O capacity=56.0gr.

24" barrel, 43.1gr, 2608fps
20" barrel, 43.1gr, 2515fps
16" barrel, 43.1gr, 2391fps

using 41.0gr, a more moderate load at 51,588psi chamber pressure
24" 2492fps
20" 2398fps
16" 2274fps

The 39.2gr of RL15 in a 24" barrel shows a chamber pressure of 45251psi and 2391fps.

 

[Michael Eichele]

Real world velocities with the 190 and RE 15 for me has been 2657 from a 24" factory tube at max loads. From a 26" custom barrel, velocity has been higher than that. A bit above 2700.

If you really want to get down and dirty with 190's at high velocity with safe pressures in the 308, look at Vihtivuorui N-540. You will be amazed. I have run them at over 2750. 2723 was the sweet spot. VV powder is much more expensive, but gives you very high velocity at good pressures with phenominal accuracy.

As always, start low and work up in 0.5 grain increments.

 

[Kevin Thomas]

Trooper,

As an aside, it's not just about the velocity that can be attained. Generally, the 190 SMK runs best at right around 2,450 fps from a .308, sort of a sweet spot, if you will. It can be run faster than that from the 308, but generally, there's a noticable loss in accuracy that accompanies the higher velocity. This is very well known among the LR HP target crowd (or at least it was, a few years back when this bullet was commonly used in that game) but there may be some differing opinions in the hunting community/forums.

Used to use this bullet a lot when I (and most everyone else) still shot .30s, the 6.5s hadn't been discovered, and dinosaurs ruled the Earth!

Kevin Thomas

 

[Michael Eichele]

Kevin,

What you say is very true however this old sweet spot was using older powders. some of the newer ones such as VARGET and VV 500 series prefer more velocity to find the sweet spots.

 

[Kevin Thomas]

Hey Michael,

Burned a lot of Varget in this combination, and found this same velocity level to be true for that combination as well. Newer powder, yes, but there's not that much difference in the technolgy between the Varget and the old IMR stuff. Haven't tried the V-V, so I'll defer to your experience there. I've heard some really terrific things about the entire N500 series that I really do need to give in a shot (HA!). I'd like to try some N540 in my Service Rifles, but no time to work up a load, de-bug and establish hard zeros between now and Perry. That one snuck up on me fast this year!

Appreciate the input!

Kevin

 

[CavTrooper76]

Interesting information fellas, thank you!

The "sweet spot" thats being talked about seems to line up with what Ive got going on. Going above 39.2 grains of RE-15 opened up the groups significantly, however, I havent gone above 41gr to see where it might take me. Ive loaded up some rounds between 40-43 gr in .5 increments to see a) my rifle handles the hotter load and b) if its gonna shoot any better/worse/the same then the load Im going with now.

 

[Michael Eichele]

I have found 43.5 of RL15 to be a very good load in more than one 308. Velocity is around 2650-2700 depending on the stick. Never better than .5 MOA accuracy but never any worse either. It is a good all around load and good balance between accuracy and speed.