Higher than expected velocities

Jnmullins

Member
Joined
Mar 1, 2020
Messages
15
Location
Louisiana
I have been testing loads for my Ed Brown 300 Wm and have been getting velocities that are higher than expected with H1000. For example, 76.0 gr H1000 gives me an average of 2930fps and excellent accuracy with 200gr Partitions, but the Nosler manual shows 2851 fps at a max charge of 78.0 gr and Hodgdon lists 2882 fps at a max of 79.0 gr. I am seeing no pressure signs such as sticky bolt lift or excessively flat primers. Any ideas or thoughts?
 
Could be a number of things. Is your barrel longer than their test barrels? Do you have 5R rifling, brass, etc. If you dont have any pressure signs, I wouldnt be concerned as your rifle is different than the test rifles. Hodgdon data seems a bit conservative too. Every rifle is different.
 
It's doesn't have 5R rifling but is 26". I am using hornady brass and seating to .050 off the lands, which is still pretty far out in this rifle. Thanks for the info. I just wanted to make sure I wasn't missing something. I'm not used to seeing velocity numbers greater than the book - it's usually less for me.
 
It's doesn't have 5R rifling but is 26". I am using hornady brass and seating to .050 off the lands, which is still pretty far out in this rifle. Thanks for the info. I just wanted to make sure I wasn't missing something. I'm not used to seeing velocity numbers greater than the book - it's usually less for me.
Most of their test barrels are 24" so expect around 50fps increase for your 26"
 
It's free speed! If your brass is holding up well, no pressure indications, I'd say your ok. I just measure brass a lot. Particular attention to primer pockets since I have been using Nosler brass. I can't push mine as hard as some do on my 7RM.
 
Some powder lots are faster than others. Also some barrels are faster than others. I have a Cooper 92 Backcountry rifle with a 24" barrel, 6 groove, chambered in 7 RM. I'm shooting Barnes 145LRX Bullets at a accuracy velocity of 3240fps at a elevation of 2800. Stupid accurate. Shooting .25moa.

Brian
 
Warning! This thread is more than 4 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.
Top