Slow Barrel???

[dragman]

I finished load development today finally for my 6.5X284 and I have now got the 140VLD bergers to shoot. I am shooting 51 grains of 4831sc with winchester brass and a CCI 250 primers. I tried many loads and different powders including H4350, RL 22, N165, and IMR4831. I am happy that is is shooting consistantly around 1/4 MOA @ 100 yards. only thing is it's only going 2875fps???? My last one was shooting 2850 with a grain and a half less and most say that with the 51 grains I should be around 2950-2975. I am not a speed chaser not gonna change this load it just shoots to well but just curious could this be a slow barrel or is there something I am missing???

 

[TonyR]

I had a 7mm barrel that was 100 fps slower, grain for grain, than others. My 31 inch Krieger 6.5X284 barrel shot the 139 Scenars at 2950 fps with 51.5 gr on H4831SC. Without knowing anything about your barrel, I would say that 2875 fps is withing the range I've experienced.

 

[bheadboy]

bbl , throat, lands groves dimentions and finish, as well as the metal itself, all make a difference, cases and bullet lot all can cause this

Bob

 

[dragman]

what is the over all length that most people are running 140 berger VLD's at??? and are most people up in the lands with them???

 

[Keith Glasscock]

How many rounds?

I had a barrel that wouldn't make any speed at all (50 - 100 fps slow) until it got to ~250 rounds then I had to back the load down ~ 1 grain to get it to shoot again...

 

[dragman]

How many rounds?

I had a barrel that wouldn't make any speed at all (50 - 100 fps slow) until it got to ~250 rounds then I had to back the load down ~ 1 grain to get it to shoot again...

good point I hadn't thought of that. Gun has 115 rounds on it as of yesterday.

 

[Keith Glasscock]

Take a look at Jay's data. It shows how the velocity changed from his barrel over the course of a couple of hundred rounds.

http://forum.accurateshooter.com/index.php?topic=3782963.msg36047799#msg36047799