03-27-2014, 03:29 AM
NOTE: I started this post several hours ago, and in the meantime, some of these questions have been answered. Sorry.
Kind of... .the leade and throat combination of the SAAMI .223 Rem was designed light short bullets. The leade and throat of the 5.56x45 are considerably longer. This allows longer bullets to be used, and in fact the specification of the round reflects that. It is completely possible to get a 5.56 x 45 cartridge that won't work in SAAMI-chambered .223 Rem rifles Worse, if the bullet "jams hard" into the throat, chamber pressure can get very high, possibly breaking a bolt or worse. It is not uncommon to see the warning "For .223 Remington ammo only" marked on a rifle.
Fortunately, it seems that most of the 5.56x45 ammo is toward the low end of tolerances and fits in the smaller chamber.
The Wylde chamber has a leade-throat combination designed to safely fire any in-spec military 5.56x45 ammo as well as .223 ammo. The Wylde leade-throat combination is longer than the .223 Rem. The very fact that the Wylde chamber exists indicates that there is a chance of danger with a .223 Rem chambering a military round. I suspect that many barrels marked .223 Rem actually have a chamber close to the .223 Wylde.
In some respects, Grendel ammo is like the 5.56 x 45 ammo. It usually works in the variants, but not always. Some may remember that some of the first Hornady Grendel ammunition did not fit in some of the variants but worked fine in rifles with the standard Grendel chamber. Many have tried to forget the finger pointin', name callin' and mud slingin' that occurred at the time. To my recollection, one of main problems was that the variants did not have a generous radius on the transition from the shoulder to the neck like the Grendel. The ammo was on the high side of the Grendel spec. The previous runs of ammo had been closer to the low end of the specifications and worked just fine in the variants.
Take a look at the case-to-shoulder and the shoulder-to-neck transitions on the SAAMI drawing of the Grendel chamber and ammo. Each of the transitions has a specific radius. Look at the reamer drawings for the variants. No radiususes, er radios, aw crap... They ain't rounded, dagnabit!
When a near- maximum sized case with a nice round shoulder-to-neck transition is put in a chamber that has a sharp transition, it won't go in all the way. From the outside, it looks like a headspace issue. Nope.
WARNING, CAUTION, AND OTHER SCARY WARNINGS.
DO NOT SMACK THE END OF A LOADED ROUND WITH A HAMMER TO SEE IF IT WILL FIT THE CHAMBER. THIS FALLS UNDER THE CATEGORY OF "STUPID STUFF."
hm2 clark Wrote:I Kinda understand that there is a difference between 5.56 and .223. Still, both chambers and bulllets will shoot in the guns I buy. Is that the kinda distenction we are drawing here?
Kind of... .the leade and throat combination of the SAAMI .223 Rem was designed light short bullets. The leade and throat of the 5.56x45 are considerably longer. This allows longer bullets to be used, and in fact the specification of the round reflects that. It is completely possible to get a 5.56 x 45 cartridge that won't work in SAAMI-chambered .223 Rem rifles Worse, if the bullet "jams hard" into the throat, chamber pressure can get very high, possibly breaking a bolt or worse. It is not uncommon to see the warning "For .223 Remington ammo only" marked on a rifle.
Fortunately, it seems that most of the 5.56x45 ammo is toward the low end of tolerances and fits in the smaller chamber.
The Wylde chamber has a leade-throat combination designed to safely fire any in-spec military 5.56x45 ammo as well as .223 ammo. The Wylde leade-throat combination is longer than the .223 Rem. The very fact that the Wylde chamber exists indicates that there is a chance of danger with a .223 Rem chambering a military round. I suspect that many barrels marked .223 Rem actually have a chamber close to the .223 Wylde.
In some respects, Grendel ammo is like the 5.56 x 45 ammo. It usually works in the variants, but not always. Some may remember that some of the first Hornady Grendel ammunition did not fit in some of the variants but worked fine in rifles with the standard Grendel chamber. Many have tried to forget the finger pointin', name callin' and mud slingin' that occurred at the time. To my recollection, one of main problems was that the variants did not have a generous radius on the transition from the shoulder to the neck like the Grendel. The ammo was on the high side of the Grendel spec. The previous runs of ammo had been closer to the low end of the specifications and worked just fine in the variants.
Take a look at the case-to-shoulder and the shoulder-to-neck transitions on the SAAMI drawing of the Grendel chamber and ammo. Each of the transitions has a specific radius. Look at the reamer drawings for the variants. No radiususes, er radios, aw crap... They ain't rounded, dagnabit!
When a near- maximum sized case with a nice round shoulder-to-neck transition is put in a chamber that has a sharp transition, it won't go in all the way. From the outside, it looks like a headspace issue. Nope.
WARNING, CAUTION, AND OTHER SCARY WARNINGS.
DO NOT SMACK THE END OF A LOADED ROUND WITH A HAMMER TO SEE IF IT WILL FIT THE CHAMBER. THIS FALLS UNDER THE CATEGORY OF "STUPID STUFF."