AR tight throat, need help!

[allghilliedup04]

So have probably around 500 rounds through this rifle, the issue didnt start right away but its getting worse to the point of pissing me off. I chamber a round and they all fire no issues, however, if i go to do a brass check or un-chamber an un-fired round its a B**ch. Its super hard to get the round out and 3 times its actually pulled the projectile out of the neck of the case. The barrel is clean, the chamber is clean so it being dirty isn't an issue.

Barrel is a Black Hole Weaponry 5.56

I usually fire handloaded match ammo through it but its super tight whenever factory ammo is chambered as well

So here is the kicker. Its not tight on the casing, its tight on the projectile. You can see in the pictures were the chambered rounds have scuff marks on the ogive. one is a factory ball and the other is a handloaded vmax.

any ideas?

 

[tickled pink]

It looks to me that your chamber is way to long. If I am correct you should call the manufacture and have them correct the problem. The reloaded shells look like they are ackley improved after being fired. Are the reloaded bullets loaded to magazine length and are they crimped? I reload using Redding Competition dies and never crimped them and have never had a projectile slip forward out of the neck. I have had factory crimped bullets slip forward and become loose when ejected and then rechambered 4 or 5 times, but never with my reloads probably because the projectile is squeezed the whole length of the neck. Crimped bullets can be tight under the crimp, but maybe not be under the rest of the neck. Maybe your sizing die is not a full length die. With mine I always full length size.

 

[arocholl]

Your rifle doesn't have a tight throat, it has a short throat. What is happening is that the bullet is engaging the rifling upon chambering; which is causing the marks on the bullet and the three instances of the bullet being pulled from the case neck.

I would check the COAL of your hand loads and the factory ammo first. From there I would probably contact the barrel maker and see what they can do for you.

Also, is this a build or did you buy a complete rifle or upper?

 

[BC83]

I've had some issues with Black hole before I would call them up and replace the barrel if you have the same problem with over the counter ammo..

 

[BCP]

Short throat/chamber out of spec.

 

[mikem4045]

I have a DPMS that would do that to 3 or 4 rounds out of a hundred. Polished it out and still happens from time to time. Getting ready to junk it out and put a criterion barrel in it.

 

[allghilliedup04]

the cases are sized the same as factory. 2.25 OAL and they are not crimped. Two of my friends also have blackhole barrels and have similar issues but neither as bad as mine... but then again i use mine a hell of a lot more often too. and yes its a full length sizing die.

its a build not a complete rifle... I will contact blackhole and see what they have to say about it

thanks for the reply!

 

[bustin]

the cases are sized the same as factory. 2.25 OAL and they are not crimped. Two of my friends also have blackhole barrels and have similar issues but neither as bad as mine... but then again i use mine a hell of a lot more often too. and yes its a full length sizing die.

its a build not a complete rifle... I will contact blackhole and see what they have to say about it

thanks for the reply!

If the scuffs are all the way around the freebore is smaller than .224 and should be returned and re-throated. If there are only 4-6 square marks the bullets are jammed into the lands. Either set them back or send it back to be re-throated. Anyone with a .223 Wylde reamer could fix it.
You could remove the barrel from the receiver and insert a +.224" inspection pin into the freebore to check it.

 

[Danco411]

Had the same problem with a Grendel barrel. Some of the non Standard chambers were really short. A friend bought the rifle but it would not shoot worth a damn. Rounds got stuck. He ended up buying a Shilen match and gave me the barrel. I rented a 6.5 throating reamer from 4-D for $28. Six turns and I extended the throat by 4 thousands and now it chambers and shoots great. Simple to do and better than buying a new barrel.

 

[tickled pink]

Get the manufacturer to fix the barrel then sell it and replace it with a WOA barrel. This is what my WOA 18" varmint with 1 in 7" twist does at 100 yds.

 

[allghilliedup04]

Get the manufacturer to fix the barrel then sell it and replace it with a WOA barrel. This is what my WOA 18" varmint with 1 in 7" twist does at 100 yds.

no way i would replace my blackhole barrel with a different manufacturer. it shoot lights out and is super easy to clean with its polygonal rifling. not to mention they are a local company.

the bullet doesnt reach the rifling because the scuffs are all the way around. otherwise it would have 3 grooves which it doesnt. sounds like i will have to contact blackhole tomorrow and see what they say

 

[banditbump]

Maybe the scuffs are all around because of the polyaganol rifling? Rifles are typically more accurate if the bullets are seated on the lands but you could have pressure issues. Honestly if the chamber Mikes at go then I would just shoot it. Bring a rod in case a bullet gets stuck....

 

[tickled pink]

I wish someone would explain why is there such a big difference between the unfired brass and the reloaded brass? Something is very wrong here.

 

[trickyric]

I wish someone would explain why is there such a big difference between the unfired brass and the reloaded brass? Something is very wrong here.

Not much difference. One is annealed and one isn't . Also they are not exactly side by side.

 

[Skidmark1969]

First ask Blackhole if they are chambering there barrels or if they have it done for them. I see this happen when a solid pilot finisher is used in a CNC Lathe. Most often when this happens coolant in used and the chamber is finished in one motion. After time the front of the solid pilot finisher is worn down not opening the bore enough for the bullet to seat. Live pilot finishers are if you want a short throat enabling people who reload the ability to reach the lands with out exceeding the mag length. Then you have the hot rod chamber, some match barrels are done this way to improve accuracy. When you chamber you finish "go" -.0002 you bolt will close on a live round but not on a go gage unless you force it.

 

[allghilliedup04]

I wish someone would explain why is there such a big difference between the unfired brass and the reloaded brass? Something is very wrong here.
Attached Thumbnails Attached Thumbnails
AR tight throat, need help!-big-difference-.jpg

They are identical OAL, its just they aren't even in the photo.

I got a call into blackhole waiting to hear back from them.. ill report back my findings in case anyone else has this issue. Thinking i may just have to seat my bullets deeper?... we will see

 

[allghilliedup04]

sent my barrel back to blackhole yesterday, they got it today fixed it, gave me 100 dollars worth of free fluting and shipped it back... today. Ill get it back tomorrow. total turn around was only 2 days. needless to say impressed with their customer service.

I got a personal phone call from the guy who fixed my barrel. He said "You were absolutely right, the throat was short and I took care of it." He stayed on the phone, answered all the questions I had offered me the fluting, let me choose what kind I wanted and took care of it. He even assured me he personally set my headspace to "perfect" so I should be getting improved groups.... hard to improve on .5" groups but I was assured they would.

Can't speak highly enough about how helpful the company is. Will report back once I get the rifle back together and how it functions.

thanks for all the replies

 

[arocholl]

Glad they fixed it for you and took care of you as well.