7mm Rem Mag Loads

[PAshooter20BR]

I have a remington 700 with a 24 inch barrel. I am doing load development. I am using the 162 grain A-max bullet with 64.5 grains of Reloader 22 powder, and Federal GM215M primers. Manuals tell me that I should be over 3000 fps at 65 grains. I have chronographed my reloads and am only seeing an average velocity of 2830. Anyone using a load that is similar? Any reason that my velocity is so much lower than the manuals? I really would like to shoot this bullet around 3000 fps to keep my drop at a minimum, This is for a longer range deer rifle and this load has a big drop difference between 300 and 350 yards.

 

[M700]

There is probably a more scientific explanation than mine - but I've had a few 7mm mags, and have loaded them often with Reloader 22. Sometimes a fellow gets that published velocity, and sometimes he doesn't. My current 7mm mag falls well short, at about where yours is. I don't sweat it, the rifle still does just fine, but about 150 fps less than I'd like to see from it. I suspect it's primarily a barrel quality thing. In general I've seen higher velocities from rifles with custom tubes and fairly tight chambers than from run of the mill factory sporter tubes and generous factory chambers.

Reloader 22 is a good choice for the 7mm mag, and for bullets in that 160 - 175 grain range.

For long-range field shooting with any rifle, I use a laser rangefinder, and learn the "come-ups" by actually shooting at the range. When that 300+ yard shot comes up, I know my elevation "come ups" to make the shot.

Regards, Guy

 

[Lane]

I do not mean to be disrespectful. Could you shoot the difference between 300 and 350 yards with the load you desire? Hunting, at some point in the real world has to enter the equation. The key word I picked up on this topic is hunting. Lots of game can be taken clean with the right bullet @ 2800 fps. No disrespect to you or your efforts. Lane

 

[Recshooter64]

I know it's an old thread, but the difference could be the chronograph. You may be getting the same velocity as they are. I would use the data to compare your loads and not worry too much about getting the results that are published.

 

[Frankm]

I had to load 66 grs of R22 with my 162 AMaxes to get 2975.... and that was a 26” barrel. Didn’t get pressure signs in my rifle. 65.5-66 grs was very accurate too.

 

[STOMP442]

Upgrade your scope. Quit using holdovers this isn't the 60s anymore. It doesn't even need to be an expensive one just one with reliable elevation adjustments. If it shoots good and you hit what you are aiming at velocity doesn't matter and the deer your killing will never know the difference of 150fps especially at that range.