Grendel II chamber

[LRRPF52]

.223 Remington is SAAMI MAP rated to 55,000psi, whereas 5.56 NATO is a 62,000psi cartridge and chamber. Two different animals from a pressure containment standpoint.

The original .222 Remington is rated to 50,000psi MAP, and that is what the AR15 was built around when it was just a prototype in Armalite's solicited development for the High Velocity Small Caliber Rifle contender for the Army.

[Tedward]

Then came Bill Wylde and improved the whole thing, right??

[bwaites]

You don't see Wylde chambers in target rifles, but its a great compromise in the AR.

[Tedward]

Yes I was referring to AR's, not a bolt gun. I have a Loather Walther Wylde and it shoots 1/2" groups all day. When I got my Loki, 556, it couldn't hold 1" groups at 75 yards and I was very disappointed in the AR platform. That is when I ventured into the Wylde and then was looking for another caliber. After lots of reading and this forums info, I picked the Grendel over the 6.8 and 300 BO. The Grendels accuracy and reach is where its at plus being able to hunt with it in VA.

This entire throat debate is the worse 3 months dealing with the Grendel I've had. I think there are a lot of questions, or was, and asking unknown questions makes answers and responses seem so defensive like some people are trying to hurt the cartridge and I really don't think that is anyone's intentions, or at least mine.

[nincomp]

NOTE: I started this post several hours ago, and in the meantime, some of these questions have been answered. Sorry.

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."

[LRRPF52]

M193 5.56x45 and M855 5.56 NATO have totally different ogive profiles as well. M193 is much more prone to jamming the lands on a .223 Rem chamber, whereas M855 has a longer radius for the ogive. It's a very sharp bullet, especially for a military projectile.

[waveslayer]

It is critical that people actually contact those with whom they are doing business!

The solution of "scraping" the throat is not one that I would have foreseen from Satern, but if members are happy with it, I feel like it is one solution.

BUT...the board exists to help members, and not to hammer on anyone for their decisions or business practices. Satern has made thousands of Grendel barrels, and until this last episode with the Liberty barrels, I had heard very few complaints! I have two myself, and they are great barrels.

Work with whoever made your barrels, and try to work something out between you that is satisfactory to both, please!

Internet scandal is all to easy a trap to fall into. Lets not create ill will where none is necessary!

I haven't read all the posts, based upon this response here is my story.
Had a short throat, contacted Satern about it. They were awesome, great to deal with. Had my barrel back in a week. Loaded some SST 123gr with CFE. OCW test completed. Half inch groups from 3 different powder charges.
I'm happy with the end resuly. Is it a scraped throat... i guess, but I'm happy with it.

[BluntForceTrauma]

Good deal, wave, and that's what it's all about! Hope the rest can finally move on as well.

John

[WildBill3/75]

Good deal, wave, and that's what it's all about! Hope the rest can finally move on as well.

John

It is critical that people actually contact those with whom they are doing business!

The solution of "scraping" the throat is not one that I would have foreseen from Satern, but if members are happy with it, I feel like it is one solution.

BUT...the board exists to help members, and not to hammer on anyone for their decisions or business practices. Satern has made thousands of Grendel barrels, and until this last episode with the Liberty barrels, I had heard very few complaints! I have two myself, and they are great barrels.

Work with whoever made your barrels, and try to work something out between you that is satisfactory to both, please!

Internet scandal is all to easy a trap to fall into. Lets not create ill will where none is necessary!

We can HANKA, unfortunately not the way most would of hoped for. We ordered a 6.5 Grendel chamber. Most of us do not want a bastardized chamber.

I finally talked with Lindsey.
Unfortunately, her boss decided to stick with their normal BS "the chamber is to SAMMI spec" and they will not fix my barrel with a 6.5 Grendel chamber.

I was not to hard on Linsdey, she just works there but this situation has really burnt me. I will NEVER own a Satern barrel again.

[babaganoush]

This entire throat debate is the worse 3 months dealing with the Grendel I've had. I think there are a lot of questions, or was, and asking unknown questions makes answers and responses seem so defensive like some people are trying to hurt the cartridge and I really don't think that is anyone's intentions, or at least mine.

You're half right on this, Tedward. It has been a miserable three months. I cannot help but see the second part of your comment as nothing more than insincere. Whether or not you are trying to "hurt the cartridge" is irrelevant. Your participation in the debate has shown you constantly playing devil's advocate in the Liberty Barrel debacle. Add to that the fact that you post in here, claiming to play nice, and turn around and visit your buddy's board carrying tales and distorting what is said here.

I, for one, have made up my mind that you have no credibility here and have done very little beyond rabble rousing. I cannot speak for others, but I find your two-faced behavior detestable.

Good day, sir.

[BluntForceTrauma]

Unfortunately, her boss decided to stick with their normal BS "the chamber is to SAMMI spec"

Yeah, dang, man, if they stick to the line "the throat is not part of SAAMI," I don't know how that's defensible. It would be nice to have a qualified person take a cast of the chamber and take careful measurements.

John

P.S. If my comment was poorly worded, it certainly wasn't directed at those of you who are victims of this whole cluster. . . .

[BluntForceTrauma]

you post in here, claiming to play nice, and turn around and visit your buddy's board carrying tales and distorting what is said here

I've been wondering about that, myself.

John

[JASmith]

Yeah, dang, man, if they stick to the line "the throat is not part of SAAMI," I don't know how that's defensible. It would be nice to have a qualified person take a cast of the chamber and take careful measurements.

John

Maybe we should buy stock in companies that produce chamber casting materials.

[BluntForceTrauma]

Someone please educate me. Anybody have access to some standard SAAMI drawings in, oh, .223 Remington or .308 Winchester that they can post? Are the throats actually specified in those drawings?

John

[JASmith]

Do a Google search with the key words "223 remington saami" and the link to a PDF download is probably going to be the first item.

The title is "223 Remington.pdf - SAAMI" and the drawing that downloads indeed has a freebore and throat spec.

Doesn't seem to have much freebore and the taper is 3 degrees and change.

There is also an excellent photo of the chamber and throat here: http://www.m4carbine.net/showthread.php?...ifferences

[BluntForceTrauma]

Thanks, Joe, it appears it's safe to say that throat dimensions ARE a part of any standard SAAMI spec.

John

[JASmith]

You're welcome!

Am hoping someone can do a good macro photo of the 6.5 Grendel Chamber Gauge. That would help a lot!

[nincomp]

Here is a link to the SAAMI site. After a couple of menus, you get here:
http://saami.org/specifications_and_info.../index.cfm

The site has an annoying quirk. When you get the rifle, pistol and revolver, or other PDF sheet, the hotlinks to the individual drawings do not work in Firefox. They work just fine in Internet Explorer, though.

You will see all sorts of leade and throat geometries. Most of the ones from the past 20 years or so resemble that on the Gren II. A section of straight leade followed by a tapered throat (commonly of 1.5 degrees).

[Sojorboy]

http://www.midwayusa.com/find?userSearch...Grendel+II

AR-Stoner Barrel and Bolt AR-15 6.5 Grendel (Grendel II Chamber) Medium Contour 1 in 8" Twist 18" Stainless Steel

[mongoosesnipe]

Not really surprising satern make the stoner barrels, satern made the Grendel 2 chamber.... Kind of a natural progression for the midway barrels to become Grendel 2