Hello , As you might guess I am new to reloading and trying to set up my press for bullet seating . I have read that the standard length of the .223/5.56 cartridge is supposto be 2.26 inches .. I am ready to set this die up and will be happy to set it to the 2.26 I read about in several places on the internet however the factory ammo I have and have been using is measured at only 2.17 to 2.19 this seems a bit shorter than what I am thinking it should be from what I've read . The factory ammo has worked fine in my rifle .. Spikes Tactical 16 inch barrel. ar15 . I am not sure what length to set the ammo I'm making .. I have heard something about how the longer you can set your ammo the more accurate it will be as it has less time/length to enguage in the rifleing . The other side is if you make it too long it might not "feed" reliabley ?/
Thank You for any help you can give me .. Whodathought it would e so confusing.. Don J.
It has been covered on here before but you might research the actual difference in the 223 and the 5.56. The cases basically are the same but the chamber throat is a bit longer on the 5.56. The modern 5.56 ammo is often loaded with a heavier and longer bullet such as a 62 -67 grain bullet. In some 223's the longer bullet can actually engage the rifling and cause pressure priblems. The 223 as originally designed was loaded with 55 grain bullets in most cases. There are also differences in pressures assigned as working pressures for the two cartridges. My understanding is that the 223 will fuction fine in both 223 and 5.56 chambers but that the 5.56 may cause problems in some 223 chambers. Just do a search on this site. The issue has been addressed several times. As far as cartridge (COAL)overall length, the longest that functions through a magazine is fine if your bullet does not jam into the lands and cause pressure problems.
The SAAMI and/or military maximum length is ordinarily set so that all cartridges will fit and function through a standard magazine, be it a staggered-column box magazine or a clip. The throating distance is then set so that bullets will chamber freely, yet retain a degree of accuracy and not raise pressures.
Cartridges may be shorter than the maximum length as long as the bases of the bullets do not protrude or encroach into the powder space to an unreasonable degree.
It is generally accepted that bullets should have a seating depth equal to at least one caliber. That is so to ensure that the cartridge will withstand some handling without the bullet loosening or moving into the case.
Book OAL is only what that book makers used to develop the data they list, there's no 'supposed to be' about it any more than their listed powder charges are. Find an OAL that works through your rifle and develop your load at that length.
for my AR-15 I set the bullets as long as the magizane will allow.
+1 Always check your magazines especially if they are from different manufacturers. There are often slight variations that can make or break ya if your loaded out to the edge. Nothing worse than an AR with FTF!