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F106 Fan
11-03-2011, 10:49
I am loading 6.5x284 NORMA with a 142 gr Sierra HPBT. I have measured the OAL required for the bullet to reach the lede and for a standard cartridge OAL, the bullet is 0.120" away.

In fact, if I try to get the Sierra bullet to touch the lede, it won't make contact with the case at all because of the boat-tail. So I split the difference and have about 0.060" of bullet in contact with the case mouth and about 0.060" bullet jump.

The numbers are what they are: facts. I don't see any way in the world to get the bullet to touch the lede. I could change bullets but the load is PERFECT. All the bullets in the same hole at 100 yards. Besides, that bullet is already profiled like a missle. Trying to find an even longer bullet might be problematic. Changing to a non-BT bullet doesn't seem like a solution if it takes away accuracy.

I think I decided to not be concerned, Savage knows more about rifles than I do.

This is my first foray into precision rifle. The .308 and .223 stuff I have loaded in the past was good enough but the 6.5 is kind of special.

Any thoughts on whether I should be concerned?

Richard

fredj338
11-03-2011, 13:25
There is no magic about OAL. Some bullets shoot fine off tha lands. It's bench rest perfect maybe, but the proof is always in the shooting. I like to have a min 1 caliber into the case neck, this prevents the bullet from tipping during feeding. If you are lloking for a longer bullet, try the Berger VLD. I shoot a 260ai, my 142grSMK are easily 0.10" off the lands & I can get into the 0.3" accuracy on a good days.

F106 Fan
11-03-2011, 14:45
my 142grSMK are easily 0.10" off the lands & I can get into the 0.3" accuracy on a good days.

It's the good days that I remember. I don't like to think about the others..

So, you're getting great accuracy at 0.100" so maybe I'll seat mine a little deeper. It's worth a try. Like you, I would prefer to have a little more engagement between the bullet and the case neck.

I am nowhere near max load. I'm only running about 2700 fps with 47.5 gr Reloader 22. I don't see any reason to burn out the throat when I am only shooting to 300 or 500 yards. When I move out to 1000 yards, I'll consider increasing the velocity.

Richard

fredj338
11-03-2011, 17:08
It's the good days that I remember. I don't like to think about the others..

So, you're getting great accuracy at 0.100" so maybe I'll seat mine a little deeper. It's worth a try. Like you, I would prefer to have a little more engagement between the bullet and the case neck.

I am nowhere near max load. I'm only running about 2700 fps with 47.5 gr Reloader 22. I don't see any reason to burn out the throat when I am only shooting to 300 or 500 yards. When I move out to 1000 yards, I'll consider increasing the velocity.

Richard

I really wanted to build a 6.5x284, but my 700SA wouldn't work well w/ the heavier bullets @ short mag. So the 260AI was my choice. With a 27"bbl, I get an easy 2700fps w/ the 142grSMK & have had some a few 1/moa groups @ 300, as far as my range allows. I'll get out to the desert one of these days & try some 600+ shots.:supergrin:
BTW, I would think the 6.5x284 would respond well to the same powders I am using. I liked RL22, but found it varied quite a bit from lot to lot. So I went to IMR7828ssc. Very accurate & very uniform from lot to lot. I also us it in my 280 so that is a bonus.:wavey: