In your experience, how much slower/faster is factory ammo in general? I know every barrel us unique, and there may be wide deviation, but what have you oberved?

This came to mind when I ran a friend's .243 Win over a chrony--100gr. Win PP, and they came out about 2670! They were very consistent--all within about 10 fps of each other; but SLOW!

I guess this explains, though, why he's never complained about a bullet coming apart on a deer. He's shot some big bucks with that gun, and I don't think I'll mention anything to him, other than, "shoots great."

Thanks for your thoughts,

friar

p.s. I'll probably put together a 100 gr. partition and set it up for the neighborhood of 2900 fps--assuming the barrel will allow it!

friar,

I've chronographed some factory loads in my time, and in general, many can be a bit slower than advertised. But I've been pleasantly surprised as well. A 7mmSTW I had w/ a 24" bbl. would shoot factory Remington 140 grain Core-Lokts at 3400 fps. My 300 Weatherby shoots factory Weatherby brand 165 grain slugs at 3450 fps out of a 26" bbl. Both these loads are accurate in their respective rifles, to boot.

My biggest disappointment, that comes to mind, were the Hornady Light Magnum loads in a 257 Roberts, which fell short of advertised velocities by about a 100 fps.

I've also chronographed several different factory loads in the 7mmMag, and most were right in the ball park of advertised velocities. One load, Remington 140 gr., even surpassed advertised velocities. As you are fully aware, all this can and will vary depending on YOUR rifle, of course.

I am a little suspicious of those unusually slow velocities you recorded with that 243. Did you, by chance, try them again on another day, or with another chronograph? Maybe they were just a slow lot.

Sometimes muzzle blast will alter a reading.
Back off another 10 feet and try again. The position of the sun can cause problems at time.
Keep trying things until you get the readings you want (joke).
Good Luck!

i THINK that since shooting chrony put cheap chronies in the hands of so many shooters that factory loads are FAR closer to published spec in say the last 8-10 years...

for example, 458lott, 416 rem, 300 WSM, 300 RUM, 30-06, 257 roberts, and perhaps a couple more, at generally with 5% of FPS, if the barrel is the same length.

jeffe

It's hard to make a blanket statement about the velocity of factory loads since two different barrels of the same length may very well yield velocities of 100 fps or more difference.

Having said that, there are a couple of notable calibers that typically fall short of published velocities in factory loads. As you have discovered, the .243 Winchester is one of these. Presumably because of some off-spec .243 chambers and barrels from some European manufacturers a number of years ago, the ammunition companies underload the .243, much as the 8x57 is underloaded out of caution of being fired in an old "J" bore barrel of only .318" vs. the now-standard .323".

The velocities you clocked are not uncommon in .243 factory loads. Another round that is frequently underloaded is the 7mm Rem Magnum. Why this is is anyone's guess, although one poster above actually found higher-than-published velocities from his 7mm.

It seems as if the .270 Win often comes close to published velocities. I was gifted several boxes of old (red and green box) RP 130's, and they clock around 3050 from a 22" barrel. In a 26-incher, they might well do the 3140 fps published when they were made.

I recently chronographed some WW .30-06 180 Silvertips at 2600 fps from a 24.4" barrel. This is probably a typical velocity for factory '06 180's. I've also done some WW .264 140s that only mustered 2800 fps from a 26" barrel -- anemic even by factory standards.

Bottom line is that most people expect factory loads to fall short of published velocities by 50-100 fps, while there is an occassional lot that exceeds published specs by a few fps. It is a validation of these expectations that there is a great deal more remarking when a factory load exceeds published velocities by 25 fps than when it falls short by a hundred.

Chronographing factory loads has made me glad to be a handloader...though some occasionally surprise to the upside.

Yet to see a fast Remington factory load.

Has anybody?

Thanks everyone,

I was suspicious of the chrony too, but my .270 loads, as well as a 30-06 load, produced velocities that were in the ballpark of what we thought we might see.

One thing I appreciate more because of this little episone is the format Hornady uses for its manual--"ballpark" velocities at 100 fps intervals.

Have a great summer!

friar

I find that "usually", Federal ammo is right up there, while the other guys tend to always be well uder.

The last great Remington Ammo had, were 180 gr Ultra Core Lokt at over 2700 in the '06.