I have a 6mm Remington and am in the process of working up a load for it. I have the Hornady 100 gr Spire Pts shooting under 3/4" for 3 at 100 yds and will check with a switch to Fed GM210M primers to see if that helps. If not, it's done.

I was scanning the reloading manuals (as represented in one of the small books for a single cartridge) and the Nosler data for the 85-gr Partition jumped out at me. Their load out of a 24" barrel using 49 gr of RL 19, Fed 210M primers, and the 85 gr Partition listed a max MV of 3470 fps. The other bullet/powder mfrs' data didn't seem to come too close to those numbers, generally running 200-250 fps slower.

Anyone have any ideas why the Nosler data shows so much better?

Just remember that ALL loading data, whether from an individual or powder/bullet company, is a guide line. They are using their rifle/bbl. not yours or the other guys. When starting w/ a new caliber, I'll look at as much data as I can then work up my own loads. I have found Nosler to be a bit optimistic w/ most loads & spot on w/ others.

Nosler uses a min-spec barrel and universal reciever for their testing. Most (not all) other manual writers test in common firearms, Speer, Sierra, ect.

I have used that data, with an 85 grain Sierra HP and a 85 grain Speer SP... in a Rem 700 in a Long action, with the bullet seated to magazine length... with a 24 inch barrel...

In that rifle, under those conditions, my velocities exceeded those numbers in the Nosler Manual...

This is with a 6mm Rem, not an AI version...

The Nosler Number 5 manual has backed those velocities back about a 100 fps, from the Number 4 manual....

Mine still exceed the number 4 manual's numbers by a little.. but under 3500 fps usually...

Sometimes the load manuals have "typos" so to speak. One of my Barnes manuals has at least one that looks incorrect, and at least one in the Lee manual. It's called "someone didn't proof read the manual carefully enough". Whenever a published load deviates around 150-200 fps or more from the "norm"(3 or 4 other manuals), you might want to be a bit suspicious. The coated Barnes bullets often show a healthy normal increase, but as I recall one of them was totally off the wall.

I can only get 3100 from 87 gr Hornady with RL 19. My 7 RM gets 3300 from 140 gr bullets and 67 gr of RL 22 which is less than the Nosler load. Each barrel is different.