Looks like I got a short chamber

[pajasonc]

AA has fixed (usually replaced) several forum members barrels that weren't even AA barrels in the past. Sounds like you're assuming that all their chambers are cut short, when that just isn't the case, and that's assuming this is an issue with the chamber and not ammo. Every company has a product they let out that doesn't meet their standards.

How they deal with it after that determines the reputation of the company.

LRRPF52 should I call AA and tell them about the barrel or try another lot of hornady ammo? Like I said the upper runs fine normally I had two issues both when I didn't let the bolt slam forward, I thought maybe the upper just needed broke in. Then I read your post on AR15.com on how to check for a short chamber. Tried it with wolf and it fell right out. Tried both hornady sst and amax and the round stuck and left a small circle on bullet near the tip and require a very light tap from a cleaning rod to free them. Accuracy with all ammo has been really good brass and primers look ok Been busy all week with work so I haven't had time to call AA.

[LRRPF52]

LRRPF52 should I call AA and tell them about the barrel or try another lot of hornady ammo? Like I said the upper runs fine normally I had two issues both when I didn't let the bolt slam forward, I thought maybe the upper just needed broke in. Then I read your post on AR15.com on how to check for a short chamber. Tried it with wolf and it fell right out. Tried both hornady sst and amax and the round stuck and left a small circle on bullet near the tip and require a very light tap from a cleaning rod to free them. Accuracy with all ammo has been really good brass and primers look ok Been busy all week with work so I haven't had time to call AA.

If you're not happy with something, especially functionality with factory ammo, I assumed you had already contacted them.

If you're seeing rifling engagement on the projectile, it won't fall out of the chamber, and requires a cleaning rod to remove it, that sounds like it's jamming the lands.

If you can't extract it with the charge handle, there's a problem, but it's easily fixed with a finishing reamer and polishing of the chamber.

It happens to the best of them.

[LRRPF52]

I didn't call manufacturer because I was not sure the barrel was %100 short chambered and I didn't know if someone would suggest something that could be done to fix the issue , without me having to tear it apart ,ship it back and put it back together. Going from previous post it seemed likely my barrel is short chambered as the hornady rounds stick, wolf ammo doesn't. I also didn't notice any high pressure signs so I didn't know if I could shoot another 200 rounds and the chamber would open up a bit or if it was unsafe and it should be sent back right away. Which is why I was asking.

But I did also add that maybe the grendel 2 chamber wasn't as bad as people have made it out to be because there seems to be a lot of post around about people getting short chambered saami barrels. From what I gather the saami spec is best but it must be much harder to make barrels that are in spec with the compound throat.

There are several guys with unknown or Grumble 2 chambers who have contacted me via PM with short chamber issues, including excessive high pressure signs. Some are reluctant to send them back because they are shooting so well (this is common when the bullet doesn't jump at all). I've seen it on other cartridges as well with rifles I have owned or that people have brought to me, in .223 Wylde and .308 Win.

One particular .223 Wylde from one of the most renowned companies for making SPR profile barrels shoots lights out with 77gr and 69gr OTMs, but jams the lands and blows primers with M193. Owner asked me what he should do. My recommendation was either shoot the target ammo with longer ogive radii, or have it reamed so he can shoot the tangent ogive 55gr FMJBT fodder and possible lose the accuracy he has (shoots bug holes with 69gr SMK and 77gr SMK).

So this type of thing is not limited to any particular chamber. Another problem with the variant chambers that have no industry standard to them is that you're at the mercy of the reamer maker to tell you what the spec is, and they can and do change it to fit their interests.

How do we even know what the variant chambers are held to for throat length? They certainly aren't being held to set length in production, as I've seen them run anywhere from ogive contact at 2.250", to 2.340" with the same bullet. One would be fine from the mag with that particular bullet, and one has to be single-loaded to get even near .020" off the lands.

With a properly-cut SAAMI chamber, I can load everything from an 85gr Sierra HP Varminter at mag length, to 140gr AMAX at mag length, no jamming the lands.

All the 123gr bullets shoot great for me, as do 129gr SST, 129gr ABLR, in multiple barrels, all run at mag length COLs.

That's the whole purpose of the SAAMI chamber, to work well with a wide range of bullets when loaded to AR15 mag-restricted COLs.

If the leade is short in any of the cartridge chambers, you will see a certain bullet profile work well, usually more streamlined target bullets or shorter bullets, while longer and heavier bullets with an ogive that hits the lands early will jam.

If any rifle you have is this way and you want it to be able to shoot tangent ogives or some of the heavier bullets loaded to published COLs, you can have your chamber finish-reamed and polished.

[AZBackcountry]

AA barrel 6.5 Grendel 5 Shot Group 7 at 100yrds 2nd barrel RESIZED.jpg
I had a problem with AA. Bad chamber due to contracted barrels that they sell. The 20" SS Heavy barrel with matching bolt was a 1:9 twist instead of the 1:7.5 that I ordered. I ASSUMED low priced barrel the twist must have been a misprint. I used different factory loaded ammo Hornady and AA. All of it shot shot horrible. I called, "Yup, send it back ASAP". I had to pay the shipping and received a barrel with no markings at all from AA that is so poorly chambered that it mis-forms the brass sidewall to egg shape and sticks coming out. A Smith friend of mine said that it was a dull reamer cutting the chamber. The picture is Hornady 123 Amax factory ammo at 100 yards. Bill doesn't run AA any more. They told me that there is no accuracy guarantee. I bought a JP barrel with matching bolt, installed it on the exact same Areo Enhanced upper with Leupold Mark AR 4-12x40mm Mil PEPR mount that I never removed and same Areo lower. Shoots 3/8 groups with the same ammo. Shame on AA.

[bakabone25]

There are several guys with unknown or Grumble 2 chambers who have contacted me via PM with short chamber issues, including excessive high pressure signs. Some are reluctant to send them back because they are shooting so well (this is common when the bullet doesn't jump at all). I've seen it on other cartridges as well with rifles I have owned or that people have brought to me, in .223 Wylde and .308 Win.

One particular .223 Wylde from one of the most renowned companies for making SPR profile barrels shoots lights out with 77gr and 69gr OTMs, but jams the lands and blows primers with M193. Owner asked me what he should do. My recommendation was either shoot the target ammo with longer ogive radii, or have it reamed so he can shoot the tangent ogive 55gr FMJBT fodder and possible lose the accuracy he has (shoots bug holes with 69gr SMK and 77gr SMK).

So this type of thing is not limited to any particular chamber. Another problem with the variant chambers that have no industry standard to them is that you're at the mercy of the reamer maker to tell you what the spec is, and they can and do change it to fit their interests.

How do we even know what the variant chambers are held to for throat length? They certainly aren't being held to set length in production, as I've seen them run anywhere from ogive contact at 2.250", to 2.340" with the same bullet. One would be fine from the mag with that particular bullet, and one has to be single-loaded to get even near .020" off the lands.

With a properly-cut SAAMI chamber, I can load everything from an 85gr Sierra HP Varminter at mag length, to 140gr AMAX at mag length, no jamming the lands.

All the 123gr bullets shoot great for me, as do 129gr SST, 129gr ABLR, in multiple barrels, all run at mag length COLs.

That's the whole purpose of the SAAMI chamber, to work well with a wide range of bullets when loaded to AR15 mag-restricted COLs.

If the leade is short in any of the cartridge chambers, you will see a certain bullet profile work well, usually more streamlined target bullets or shorter bullets, while longer and heavier bullets with an ogive that hits the lands early will jam.

If any rifle you have is this way and you want it to be able to shoot tangent ogives or some of the heavier bullets loaded to published COLs, you can have your chamber finish-reamed and polished.

What would be the best place to send a barrel to have the finish-ream and polish done?

[bakabone25]

Im pretty sure my odin 18" is also a short chamber. Even the factory eld hangs up slightly in the chamber.

[Commander184]

Check your bolt face depth first. I cried wolf once apon a time.

[diddlyv]

baka have you spoken to Odin??? Other threads indicate they stand behind their work. I don't know personally as my 20 inch odin shoots the factory 123 SSTs just fine and all the groups with it have been sub MOA so I have not had to deal with their customer service. They were most helpful getting my order processed before they actually went live on the website with a new shipment of 20 inchers when they were listed out of stock. As I had asked them about it several weeks before they got the shipment.

[diddlyv]

Not sure if close to rifling is always necessary my Rem 40XBR shoots about 1/2 min with 190, 180 175 and 155 SMKs the 190s don't touch the rifling and the 155s sure as heck dont get anywhere near close. Generally seat everything so the base is close to the base of the neck so the 190s have a whole lot of bullet sticking out the 155s not so much. Guessing the chamber has a pretty long lead but really close to .308 in diameter so the bullets dont get much of a chance to go anywhere but straight.

[bwaites]

Gentleman,

I just had email conversations with Alexander regarding this issue, and there have been no phone calls regarding short chambers recently. I just received and built a 16" last night that shoots 1 inch groups at 200 yards and sub 1 MOA at 400 yards with factory Hornady Black ammo, so I don't believe its an epidemic.

PLEASE call and discuss any issues with the manufacturer, whether they be AA or any other.

[bakabone25]

baka have you spoken to Odin??? Other threads indicate they stand behind their work. I don't know personally as my 20 inch odin shoots the factory 123 SSTs just fine and all the groups with it have been sub MOA so I have not had to deal with their customer service. They were most helpful getting my order processed before they actually went live on the website with a new shipment of 20 inchers when they were listed out of stock. As I had asked them about it several weeks before they got the shipment.

I have not yet contacted odin on this. I am trying first to make sure there is actually an issue, and not just my ignorance. From what i can tell so far is that a new factory load horn, 123 eld will go into chamber by hand, but will need a nudge to fall out freely. with that being said, this gun still will shoot the factory load near 1/2 moa.
May not be a major issue, however if im to understand correctly the nosler bullets like to be just a lil shy of the lands. ? And that will likely be my preferred
projectile. I have already been able to load a few rounds of the 120 with 8208 and get .47 moa at 2535 fps. 5 rounds with sd of 8. So maybe the barrel is fine as is.
I thought i understood that a loaded round should be able to freefall from the barrel of its own weight. Hey im def still in the learning stage here. ALL advise is welsome.
Thanks for the input
Ken

[bakabone25]

I have check bolt face depth . .all is checked out in spec.

[pajasonc]

I have not yet contacted odin on this. I am trying first to make sure there is actually an issue, and not just my ignorance. From what i can tell so far is that a new factory load horn, 123 eld will go into chamber by hand, but will need a nudge to fall out freely. with that being said, this gun still will shoot the factory load near 1/2 moa.
May not be a major issue, however if im to understand correctly the nosler bullets like to be just a lil shy of the lands. ? And that will likely be my preferred
projectile. I have already been able to load a few rounds of the 120 with 8208 and get .47 moa at 2535 fps. 5 rounds with sd of 8. So maybe the barrel is fine as is.
I thought i understood that a loaded round should be able to freefall from the barrel of its own weight. Hey im def still in the learning stage here. ALL advise is welsome.
Thanks for the input
Ken

Does the round fall free with a hard tap on back of upper or butt of gun? If not there is a problem. I am the OP took mine out today to double check things. First amax(factory load) came out with charging hand but it took a lot to get it out tried another and it extracted fairly easily but the round back in and couldn't get it out pulled hard on charging and the round came out without the bullet! Used a cleaning rod to get the unfired round out of the barrel. Called AA this morning but got a answering machine. Left a message. Also emailed them. We will see how long it takes them to get back to me and what they say.

[bakabone25]

Yes it does fall out will just a slight upwards bump of the stock. I did notice that my reloads were a little tighter the the factory loads. But again they seem to cycle fine.
I did try to load the nosler coal to 2.24 trying to create some space and followed the pressure signs of the shells. Not really seeing pressure signs.

[pajasonc]

Contacted AA on monday morning by email and phone. Service number goes straight to voice mail. As of 12:40 today haven't heard back from them yet. Just a side note had to return a primary arms red dot they answered phone and directed me to their website for a return. RA was issued within the hour. Impressed with primary arms service.