Thread: chrony on factory loads

Well box factory ammo is nearly always tested with 24 inch proof barrels , sometimes 26 inch. Most seem to test less than stated but will by some point
anyway if using a shorter barrel. Couple i tried in factory over a chrony were only 50-90 less and that was with a 24 inch barrel.
Also, as im not sure(someone will know) arent factory box speed from straight from the muzzle? (other than a few feet with a chrony) Just thought i read that somewhere.
Plus a top end chrony will be more accrurate than some cheaper models and different rifles barrels will affect the speed also.
they never going to be perfect

Originally Posted by deer243

Well box factory ammo is nearly always tested with 24 inch proof barrels , sometimes 26 inch. Most seem to test less than stated but will by some point
anyway if using a shorter barrel. Couple i tried in factory over a chrony were only 50-90 less and that was with a 24 inch barrel.
Also, as im not sure(someone will know) arent factory box speed from straight from the muzzle? (other than a few feet with a chrony) Just thought i read that somewhere.
Plus a top end chrony will be more accrurate than some cheaper models and different rifles barrels will affect the speed also.
they never going to be perfect

Factory ballistics are "corrected to the muzzle". This means that the velocity is raised a little from what you would read on a chronograph. Generally the difference is small. 10 or 20 fps.
GPM