Originally Posted by RL357Mag
National Match competitors use 77 - 80 gr. bullets out to 800 yds., the only problem is that they have to be loaded singly, since they will not fit in the magazine.
I believe that the way this was written, it was misconstrued to mean that BOTH the 77gr and 80gr bullets had to be singly loaded. The 80 gr bullet was not singled out here, therefore your meaning was not perfectly clear. No harm no foul....
Although as you say, the 75 / 77gr bullets do not HAVE to be seated to magazine length, every NM shooter I've met personally that shoot these bullets DO load them to magazine length for one simple reason. Rapid fire strings in the National Match courses. It's the KISS method. If I loaded some longer for the slow fire stages, I can almost guarantee you I would get them mixed up at some point, and that would just ruin my day - so I won't chance it myself.
The 80 grain x-ring seeking, mini-missiles are another story entirely because you are dealing with slow fire strings at the 500+ yard distances, and have plenty of time to do so. My 80gr loads are stretched to 2.555" OAL for my Colt H-bar w/ 1:7 twist, and they are still
.020" off the lands in the NATO chamber. My EA rifle with a Krieger 1:7.7 only needs a mere 2.390" OAL for the same jump to the lands.
There again, I have to be VERY careful to bring the correct length ammo with me depending on which rifle I have with me.
Excellent explanation on exceeding the RPM's of the lighter weight thin skinned projectiles.