Fast barrel?

[Tcole75]

I have a factory Remington 700 30-06. Shooting 178 eldx with imr 4451 55.5 grains 20 thousands jump. 24 in barrel. hodgon says I should be around 2750 but I'm getting 2950. I'm getting .76 moa out of it and I'm close to pressure. When I went. 3 grains higher I started getting ejector swipe on the brass but everything below this charge shot like crap. I was getting around 1.5 to 2 moa groups with everything else. I started at 53 grains working up in .3 increments. Would you go back to the drawing board or just roll with it?

 

[nhyrum]

I'd be questioning my Chrono. 2-300 fps FASTER than published data, and, after I did a little reading, it sounds like people with your barrel length have a hard time getting anything over 2750, with a whole grain more than you are using. "Fast" barrels aren't usually that fast. Could it be though? Probably, just not in my experience, which isn't much. To me it just seems too fast to be just a fast barrel.

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[Tcole75]

Its definitely not the chrono I shot from 400 to 950 and it confirmed my chrono was correct. Im just extremely surprised its shooting this fast

 

[SDHNTR]

What is book max for that powder charge and bullet?

Do you hunt in hot weather ever?

 

[Tcole75]

The max is 55.6. I am running a silencerco harvester on it but its never sped up my Creedmoor or my 284 win.

 

[SDHNTR]

Somethings weird. I would want to shoot through another chronograph just to verify.

 

[Tcole75]

I'm going to try a labradar and see what it says but with center punching targets from 400 550 700 and 950 i think its right

 

[nhyrum]

If you were able to correctly verify that velocity at range, I don't care what the Chrono says. Physics won't ever be wrong. Now, wrong, inaccurate numbers and bad math can make it look like the physics are wrong though. If you're getting correct dope at 900 using that velocity, the only thing that I can think of that would make that happen (this is the Chrono is off by 300 fps) is your bc would have to be way friggin off, to the bad (box/used bc way lower/worse than actual bc, like you used a g7 of .184 instead of the actual.284) the fact that both of those unlikely things would have to happen to make this work just seems highly unlikely. Not impossible though. Just examples.

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[Tcole75]

I have the g7 bc listed as .278. I just don't understand how its shooting so much faster than it should be. When I get home I'm going double check everything on the rifle and my loads to make sure I didn't some how screw up but with not getting pressure signs I would think its ok.

 

[nhyrum]

Yeah, I just used the bc in the applied ballistics app, because it was the easiest way for me to look up any bc for that bullet.

I could see if, say, you had a small weight on the scale (say, 5 grains) when it was zeroed, it could make you load actually heavier than what the scale said. Not saying that happened, but it could be one explanation of why your load is so fast. If you can condole l comfortably say that did not happen, then that can be ruled out. Maybe pull one and re weigh the charge, careful to not spill a kernel.

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[Tcole75]

I use a rcbs charge master but I have a beam scale as well when I get home im going to check it on each and make sure it's correct.

 

[nhyrum]

I wouldn't say you had to check everything left, just a few. If they're all on, I'd say they're all good

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