04-10-2011, 12:37 PM
Drifter Wrote:Check out the Velocity reticles on the Nightforce website. There's an online calculator there that will show how closely your load might match up.
Drifter:
I have a Nightforce 2.5 - 10 with the velocity reticle for the Grendel. If a person gets the 'Low Velocity' design I can assure them that it will be fine to 600 yards which is where you hit the duplex. However they better be getting something near 2600 fps and are using a well designed bullet or they will be sorry.
This low velocity pattern regulates very well when I am shooting the various 120 and 123 grain match bullets and holds within plus or minus a minute at even 700 yards (had to use a hold over) which is the farthest I have pushed it. I was actually very surprised it does as well as it does but when you look at it in ballistics terms, plus or minus a minute at 700 from a fixed pattern reticle is extremely good.
My advice to anyone who can get around 2600 from a Grendel with 120 grain bullets is that they are just as well served if they get a BDC designed around the standard .308, 168 grain match loading. Of course a person can spend a huge amount of money for a BDC that has stamped on it '6.5 Grendel' but otherwise is the same as a 168 grain .308 match load.
Simple rule of thumb. To 300 and the optic manufacturer will use the same increment on his reticle or BDC. The differences are so small that it doesn't matter. To 500 and any of the patterns designed around 2600 fps using about a .400 BC bullet will be fine. Past 500 and all bets are off, particularly with a Grendel.
No BDC or fixed reticle pattern will ever be a perfect fit but if you have one that gives you precision to within + - 1 minute at 600 yards -- you have a good fit.
LR1955