AR-Stoner 6.5 Grendel barrel short chambered.

[Tedward]

I want to here what Saterns response will be. They read this Forum so Monday we will here there side of the story. There might be a misconception of the measurements being taken and I would like to hear from a barrel manufacture rather than a private hand loader.

Not discrediting anyone but let's hear from someone who has experience with the Grendel chambered AR's.

[jurassic]

.1325" is within tolerances (-.003" IIRC), but doesn't really answer the question. If I was one of the recent recipients of these AR Stoner barrels, I'd try another bolt (one at .135"), to see if that allows the factory ammunition to chamber correctly.

I have tried bolts that are .135, they work fine. I thought the same thing, a shallow bolt face and a tight chamber may be causing the problems for those who can't chamber rounds, or have them being jammed into the rifling.

[Tedward]

I didn't catch the part about the bolt depth but that could cause an issue. But not to the affect of being described. I would really like to hear from someone with a cut rifle from Satern. Or someone's measurements from Precision Firearms chamber.

Wake up out there it's 8:00 est. Get measuring.

Just kiddin. If someone can do a comparison of a Satern Button cut to any other chamber would be nice.

[PigOPs]

I've had a Liberty barrel for a year and a half. My concern right off the bat was that when I fired factory AMax I was flattening primers. Not much, but enough to make me feel like the bullet was very close to the lands. When I started reloading SST I measured. Hornady SST touches the lands at 2.255" in my barrel. For me it came down to this: I'd rather have a short throat where I can load where I want to off the lands than a long throat where my max OAL is not enough to get me there. My assumption is that you chamber is short. My barrel is very accurate and I've not had any issues with it. My $.02

[Tedward]

Reamers are one piece. The throat gets cut at the same time the chamber does. If anything I bet the bullets or Hornady gauge is touching the sides of the freebore and not the front of the lands.

Now this is a reasonable and logical response from a knowledgable Grendel manufacture. Even though he has stepped backward into the 6.8 he still knows clambering.

How bout that woohoo.... Just messin with ya but someone new to the Grendel can get confused with this trend and discourage new Grendel prospects with inaccurate information. He might have interest in the 7.62x39 or 6.8 and trying to scare people out of the Grendel. You know how this market uses all kinds of tactics. Also kidding about the second part. But resolution needs identified. By a reputable Grendel Rifling Manufacture or experienced forum member.

[jurassic]

After seeing differences with bolts I have, I bit the bullet and bought Manson Go and NoGo gauges from Brownells, they're in stock right now. I don't feel comfortable with Grendel bolts the way I do with 5.56 bolts anymore even though we should not have these issues with chambers and bolts.

[customcutter]

Did you purchase your barrel in the last 3 weeks? Since the new batch came in stock at Midway?

The 3 of us that are looking at chamber issues all purchased from the last batch of 18" AR Stoner barrels.

My barrel is an 18" barrel from the group buy here on the Grendel forum. I think they were made at the same time the Midway barrels were made, but I'm not sure.

[mccuistion]

I want to here what Saterns response will be. They read this Forum so Monday we will here there side of the story. There might be a misconception of the measurements being taken and I would like to hear from a barrel manufacture rather than a private hand loader.

Not discrediting anyone but let's hear from someone who has experience with the Grendel chambered AR's.

Ok, I'm not trying to be rude here, I am truly curious... what will their response give? Wont their decision be based on the measurements we give them? I'm just confused on how they could give input until the barrel in question is in their hands.

That said, I am calling them Tomorrow because yesterday I went to every LGS in the area and bought 140g SST, 129g SST, 120g SST, 120SMK, and 107SMK. I made dummy rounds for measurements to the lands and then loaded some of each at minimum published OAL from Alexander Arms/Hornady 9th Ed. and not a SINGLE projectile allowed my AR into battery. If measurement accuracy is in question I would be happy to upload pictures... It's damn near impossible to mess up an OAL measurements with a digital caliper. (The 140g SST had no published data, I got the load from these forums)

[XcountryRider]

It sounds like your assuming you should be using the published OALs? Every rifle is different and you should use the OAL that you measure in your chamber for each pill not whats in the manuals.

[explorecaves]

It sounds like your assuming you should be using the published OALs? Every rifle is different and you should use the OAL that you measure in your chamber for each pill not whats in the manuals.

Just for sake of the argument here, if it happened to be reamed short then by using the OAL for that chamber and the powder of the published loads could result in a potential for a compressed load at a substantially lower volume of powder.

[XcountryRider]

Just for sake of the argument here, if it happened to be reamed short then by using the OAL for that chamber and the powder of the published loads could result in a potential for a compressed load at a substantially lower volume of powder.

You have to work up a load every time regardless. Some folks get 2550fps with a 18in barrel with 31gr of CFE223 loaded to 2.265in. I load to 2.265in and i get 2590fps with a 18in barrel with 30.8gr of CFE223 well below the Hornady listed max of 31.2gr. At 31.3gr i have extractor marks.

[Trock03]

Just for sake of the argument here, if it happened to be reamed short then by using the OAL for that chamber and the powder of the published loads could result in a potential for a compressed load at a substantially lower volume of powder.

Correct me if I'm wrong here but doesn't that mean you also don't have the option of buying ammo off the shelf considering the short dimension of the "unique" chamber. Call it 6.5 Grendel Mod AR Stoner.

I'm not a reloader so I don't have the option of shortening rounds to work in this barrel. I do have a reloading set on order so hopefully in a few days it will be an option. In the mean time I've got several boxes of AA 123gr Scenars that I can't use in this good looking 18" barrel.

Assuming the issue is just a short chamber; is the fix as simple as buying/renting the appropriate reamer and slowly removing material until the bolt locks?

TC

[NugginFutz]

Correct me if I'm wrong here but doesn't that mean you also don't have the option of buying ammo off the shelf considering the short dimension of the "unique" chamber. Call it 6.5 Grendel Mod AR Stoner.

I'm not a reloader so I don't have the option of shortening rounds to work in this barrel. I do have a reloading set on order so hopefully in a few days it will be an option. In the mean time I've got several boxes of AA 123gr Scenars that I can't use in this good looking 18" barrel.

Assuming the issue is just a short chamber; is the fix as simple as buying/renting the appropriate reamer and slowly removing material until the bolt locks?

TC

+1. Being shipped a non-SAAMI spec chamber is tantamount to unwittingly owning a wildcat cartridge. Monday will tell the tale, when Satern has an opportunity to respond to the question regarding these chambers. I suspect the response will be short and sweet. "Send it back, and we'll look at it."

[mccuistion]

No, but I do feel that if I seat at minimum published OALs my rifle should at least chamber. I agree that every rifle is different, published data is just a general guide, and you adjust as appropriate but I feel this is a larger than average variance. My max is .026" shorter than the standard minimum, I've never experienced that much of a difference in any other barrel or caliber I've ever purchased. With the measurements I've recorded there's no way factory ammo will chamber and I don't feel that is acceptable.

I'm just going to leave it alone until I talk to Saturn tomorrow, I've heard nothing but good things about them and I don't see why this will end up any other way.

[XcountryRider]

I just tested various loads that i have done previously for my other Liberty barrels to see if they would chamber in the new 18in Liberty from the barrel buy. Here's the results.
129gr SST loaded to COAL 2.25in chambered and extracted smoothly
95gr Vmax loaded to COAL 2.235in Bullet stuck in chamber
120gr TTSX COAL 2.235in bullet would not chamber
100gr Nosler BT COAL 2.25in Bullet would not chamber

Yep something is off about this last batch of barrels. Sux now what?

[Lead Chucker]

Well poo... I ordered my dad a 16" stoner from midway just before christmas and got it right after. I hope it isn't like above, ill check it in the next few days to see. I built a buddy one with same barrel last year that isn't short and shoots great. So im hoping for the best!!

I agree if the champers are short they shoud be fixed, I do reload but if you cant chamber factory ammo its no good. Also you want to be able to set heavier bullets as long as possabe to increase case capasity for velocity, so it the chamber is short it will hinder that. Just my 2 cents

[Tedward]

Get a barrel at Brownells.

[XcountryRider]

So my 123gr SST and 129gr SST chamber which is a result of the position of the ogive on the bullets. Is this a change to the barrel extension or the actual barrel?

[Sputnik]

So, with what we know now, what is the common thread? What is the consensus of what is too short, too long, too fat, too skinny, etc? Is this for 16" and 18" group barrel buys as well as Midway barrels? How do us novice assemblers determine, if our barrel is not to specs? I guess we will see what is learned from Midway and Satern. Please continue to post.

[XcountryRider]

The Midway barrels were the same as the group buy barrels.