factory ammo.....claimed velocity vs. actual velocity

[1858rem]

for those with a chrono, i am aware that factory ammo does not always live up to its claims about the velocity they get, but have you reached the velocity with safe reloads?
i remember seeing a box of nosler partitiones and was amazed at the claimed velocity, like 2900fps for a 165 or 180 grain bullet (308 winchester), i dont remember, but i cant even get that out of my .308 with 168 BTHP loads, or even my 150sst's for that matter( im still about 1g under max load too), i have 19.5 inches of barrel if you measure from where the ogive touches to the muzzle so i dont think berrel length is a huge problem.


has anyone chronoed factory ammo to see what actual velocity in there rifle was, is the premium hunting ammo that is like 50 bucks for 20 any more consistent than cheap $15 federal soft points? do they get closer to the claimed velocity is what i think im asking.

 

[The Bushmaster]

I chronographed .38 Special, 357 magnum, 9mm X 19, .45 ACP, .30-30 and .30-06. all Remington Green box and all were +P except the .30-30 and .30-06. All were close (+/- a few) to advertized fps.

Yes I have met most of them as far as fps is concerned, but I don't load that hot anymore...

 

[1858rem]

that is interesting thanks for the input, i have another rifle, a ruger M77 in .204 ruger, 24" bbl and with max load of benchmark and a 32g vmax i still only get 4150 fps, id like to see how hornaday thinks they got 4250fps from their load, even over the chron i think it matched my reloads velocity, but the factory ammo was not quite as accurate

 

[USSR]

for those with a chrono, i know factory ammo does not normally live up to its claims about the velocity they get, but have you reached the velocity with safe reloads?

Easily, and then some.

i remember seeing a box of nosler partitiones and was amazed at the claimed velocity, like 2900fps for a 165 or 180 grain bullet (308 winchester), i dont remember, but i cant even get that out of my .308 with 168 BTHP loads, or even my 150sst's for that matter( im still about 1g under max load too), i have 19.5 inches of barrel if you measure from where the ogive touches to the muzzle so i dont think berrel length is a huge problem.

Don't know what ammo you are referring to, perhaps the Hornady Light Magnum? And even that ammo will not send a 165gr or 180gr bullet out of a .308 Winchester at 2900fps. About 2800fps with a 168 BTHP is a best case scenario, but that is with a long barrel. Knock off atleast 100fps (probably more) with your 19.5" barrel.

has anyone chronoed factory ammo to see what actual velocity in there rifle was, is the premium hunting ammo that is like 50 bucks for 20 any more consistent than cheap $15 federal soft points? do they get closer to the claimed velocity is what i think im asking.

I have chronographed Federal Gold Medal Match ammo, and found the velocity to be about what the claim (but, I have a 26" barrel). Because of your short barrel, you are unlikely to reach the claimed velocity for any ammo you buy. Also, the velocity obtained in one rifle will be different from another rifle even with the same length barrel. Example: I have 2 .30-06 match rifles with 26" barrels. With the same load, one gets 2875fps and the other 2950fps. Hope that helps.

Don

 

[The Bushmaster]

Good point USSR...The barrel length and the test bed that the factory uses has a lot to do with what you will get in comparison...

 

[1858rem]

(but, I have a 26" barrel)

where do you measure from? i chambered a dummy rd and then used a dowell to measure form the bullet to the end of the barrel. from the breech face it is about 22" or so

 

[USSR]

Typically, a barrel is measured from boltface to muzzle. Just stick a cleaning rod down the bore, mark the rod where it exits the muzzle, and measure the length.

Don

 

[rcmodel]

Barrel length is always measured from breach-face to muzzle.
That is the measurement you will always see listed in reloading manuals, factory data sheets, etc.

Nobody lists barrel length from the bullet tip to the muzzle.

rc

 

[1858rem]

22" on the dot

 

[Double Naught Spy]

Not only is barrel length an issue, but wear. Over time as the barrel wears, the seal isn't as good and so you don't get as much pressure behind the bullet and the velocity drops.

 

[The Bushmaster]

But do remember that revolvers are different. Barrel length is the actual barrel length not counting the cylinder...

 

[counterclockwise]

Some factory rounds (seems like more lately) are stoked up really hot and do usually meet the published velocity for the gun configuration referenced. These really hot rounds also show high pressure signs that handloaders typically back off. The big difference is that handloaders typically load at or below SAAMI MAP and the hot factory rounds go over. Factory ammo only has to fire once and hold everything together until after it is ejected.