Lee manual recommended an especiallly low charge for 4064 in .260 Remington

[vicroll91]

Went and shot my newly-barreled Remington 700. Swapped to .260 Remington. Lee manual recommended 31.7 grains of IMR 4064 so I loaded 15 at this charge. I noticed after a few shots that the primer had backed out of the pocket ever so slightly of every case.

New Sig .260 Brass
Loaded to 2.850
140g Barnes Matchburners HPBT
31.7g IMR 4064

After some digging, IMR 4064, while not ideal, is workable in the .260. Most seem to be starting at more like 38 or 39 grains. I'm thinking 31.7 grains was not creating enough pressure to keep that primer in place. Thoughts?

 

[acloco]

HIGHLY recommend using the powder manufacturer's data.

Unless a company employs ballistic testing, they copied and pasted from somewhere else.

 

[Rsadams]

Manuals are just a reference... You will often go above their max charge or be up there close to it when looking for fast bullets or long range BUT not always.... I have one rifle in .308 that a little bit higher than the middle of the charge data was as fast as factory over my crono.... You can find many manuals that don't even come close to each other... Some have starting charges that are close to max charges in other manuals.....

This is why the best advice is always start low and work up till you get what you want.... Don't go below the minimum charge though...testing is the best answer... Let the chronograph and paper tell you what's happening.... Each rifle likes something different....

 

[Minshooter]

Hodgdon Data Center lists a .260 Rem 140gr (Nosler Part.) max load @ 36.0 grs IMR4064 @2615fps

 

[Flouncer]

The older Lee manual I have states that they use available information adjusted by minus 10% for your safety. The Sierra manual refers to their ballistics testing. As RSA and Acloco said . . . . .