advertised ballistics
are the ballistics advertised in catalogs (federal, winchester,remington,hornaday) are they accurate or are they far fetched from the truth ?[?] if they are off how far off ? because i have heard they are and i have heard they are very close too . i am specifically looking at the .270 WSM but all of the big game cartridges between .270 and the .300 mags would be nice to know about too thanx for your time
any knowledge would be nice to know
any knowledge would be nice to know
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You could clock every barrel made and they would all be different due to differences in length, tolerences in chamber/throat/barrel dimensions,etc. Many of the advertised velocities are clocked out of stationary pressure barrels in ballistic labs and are usually faster than factory barrels and different lengths than the ones on the guns they sell. Factory rifles are seldom as fast as the test barrels. Just use their numbers for a guideline, not Gospel.-- I recently read an article on the 270WSM that a writer was testing. He had two new factory rifles. A Tikka T3 and a Savage. He was shooting the exact same ammo(many handloads and some factory stuff)and clocked them side by side. The Savage averaged approx. 125-150fps faster with each load, but the Tikka was slightly more accurate. Each had barrels within 1/2" of the same length, but the Tikkas have a slightly longer throat in front of the chamber(small freebore)which reduces pressure. You could handload it up to the same pressure that the Savage was operating if you so desired to spend time working up loads safely. -- Just an example of the differences you can encounter with guns......hope this helps......[8D] 0 -
To add to temblor's comments.
Marketing people put the best spin on the products being pushed, so w/ ammo you can bet that velocities will be the fastest that can be clocked in testing, and so what if the actual testing conditions are beyond what factory/field grade guns can accomplish. Let the buyer go looking for the "fine print".
Now with my jab at marketing ethics out of the way. If you handload you should have a number of reference load books and there are notes on what was used to achieve the pressures and velocities listed. You typically don't duplicate the performance listed for the loading, you come close and that is one of the reasons that all load manuals state that loads be started below maximum and worked up.
Typically you will find that any gun (rifle of handgun) will have a favorite load and that the "pet" load is usually not at the maximum load level.
Commercial ammo is loaded to perform in bascially any properly chambered rifle. Both firearms and ammo are mfg. to certain standards and thus performance can not be the same for each and every gun as there are manufacturing tolerances (+/-) in dimensions, powder load, bullet weight, chamber, leade, etc. and thus manufacturers strive to hit the median of the standards.
Lastly there are web sites where you can go to get ballistic info. and much of that data is generic. Also there are programs you can buy for your PC that will calculate ballistic performace for your input of different variables.
If you only have time to do two things so-so, or one thing well ... do the one thing!0
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