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AeroEngi
02-22-2011, 1:45 PM
So I take my new AR out to the range over the weekend. I went on Friday and on Sunday. I shot around 80 rounds through it on Friday and it ran flawlessly. Brought it home, thoroughly cleaned it (so I thought) and put it away. Took it out again on Sunday, fired around 40 rounds through and it started giving me problems. Everytime I would load a new magazine and hit the bolt catch, the bolt wouldn't fully close (it closed about 95% of the way). When I tried pulling the charging handle to remove the semi-chambered round, it's almost like the bolt was stuck. So I had to slam the butt of the stock while pulling on the charging handle to remove the round. The bolt closed perfectly fine without a round in the chamber. What do you guys think?

Thanks

Merc1138
02-22-2011, 1:51 PM
Did the brass come out really dirty? Could be that the chamber is filthy.

AeroEngi
02-22-2011, 1:52 PM
Ya, the brass looked pretty dirty.

HighLander51
02-22-2011, 1:55 PM
Were the mags full up? Try downloading 1 or 2. Also a fleck of brass could have lodged in the locking lug engagement face. Was it the same ammo as the day before? Were the mags the same? Make sure you take the mag out when slamming the butt....

maschronic
02-22-2011, 1:55 PM
are you using reloads or new ammo? i've used reloads before where the brass was not trimmed and had the same problem. the dirty chamber might also be the problem too.

AeroEngi
02-22-2011, 1:57 PM
Were the mags full up? Try downloading 1 or 2. Also a fleck of brass could have lodged in the locking lug engagement face. Was it the same ammo as the day before? Were the mags the same? Make sure you take the mag out when slamming the butt....

Ya, the mags were filled with 10 rounds. It was not the same ammo as the day before, I was using factory PMC bronze the day before and I was using reloads the day I was having problems. Of course I removed the mag before I slammed the butt of the stock :)

are you using reloads or new ammo? i've used reloads before where the brass was not trimmed and had the same problem. the dirty chamber might also be the problem too.

I was using new ammo on Friday and reloads on Sunday.

Milsurps
02-22-2011, 2:02 PM
Ya, the mags were filled with 10 rounds. It was not the same ammo as the day before, I was using factory PMC bronze the day before and I was using reloads the day I was having problems. Of course I removed the mag before I slammed the butt of the stock :)



I was using new ammo on Friday and reloads on Sunday.

Had the very same issue a while using reloads. I don't run reloads in my AR's any more. :D

EvoXRiley
02-22-2011, 2:14 PM
what brand of reloads did you use?

tacticalcity
02-22-2011, 2:18 PM
I was using reloads the day I was having problems.

This is the cause of 99% of people's troubles right here.

AeroEngi
02-22-2011, 3:55 PM
Thanks for all the feedback you guys! I was going to order some Federal XM193F from Palmetto pretty soon. Would these work ok?

CRTguns
02-22-2011, 6:52 PM
I've seen a loose gas key (snorkel lookin gthing atop the BCG) or a foobared gas tube cause this.

gemini1
02-22-2011, 7:02 PM
This is the cause of 99% of people's troubles right here.

Why? Are'nt reloads being resize to its original shape during the reloading process?

AeroEngi
02-22-2011, 7:02 PM
I've seen a loose gas key (snorkel lookin gthing atop the BCG) or a foobared gas tube cause this.

Well hopefully neither of these is the case. The BCG is brand new. I will try some good factory ammo and thorough cleaning/lube and see if the problem will go away. If not, then you're probably right. Thanks for the feedback.

gemini1
02-22-2011, 7:34 PM
Well with the gas key, you can just take the BCG out and check to see if its loose or play. I assume you have a chamber brush to clean the chamber?

AeroEngi
02-22-2011, 7:45 PM
Well with the gas key, you can just take the BCG out and check to see if its loose or play. I assume you have a chamber brush to clean the chamber?

Yes, I've checked the gas key and it's on there pretty solid. I will check it again tonight just to be sure. I recently bought a chamber brush and used it only this last time that I cleaned the rifle. This was after the problems I was having so I'll have to wait until my next range trip to see if the cleaning/lube worked.

I would also like to note that the BCG was bone dry when I had the problems. I didn't know how to lube the BCG until my friend showed me after I was having issues.

G-forceJunkie
02-22-2011, 10:13 PM
Supposed to, doesn't always happen.Why? Are'nt reloads being resize to its original shape during the reloading process?

17+1
02-22-2011, 10:39 PM
Why? Are'nt reloads being resize to its original shape during the reloading process?

Not necessarily.

If the FL die (SB or standard) isn't set up properly the shoulder will not bump back far enough and the case will not be fully sized. Also, if the case is too hard, as in sized multiple times and/or not annealed, the brass will spring back to where it was after it goes through the dies.

This has happened to me. I tried to get fancy with my 223 reloads by sizing them to the chamber of my wifes Stag. They run awesome in her rifle but stick like a SOB in my CMMG if I try and clear the rifle. Have to strike the butt sometimes...keep the chamber clean, this will alleviate the sizing issues for at least a few dozen rounds. The root cause is most likely inadequate sizing operation though.

SgtJT27
02-22-2011, 10:45 PM
If you're shooting reloads done by some one else ( which I don't recommend), check the shoulders diameter for flares or deformities; as this would cause not to chamber properly.

jasonnorcal
02-22-2011, 10:46 PM
I would also like to note that the BCG was bone dry when I had the problems. I didn't know how to lube the BCG until my friend showed me after I was having issues.

Running her dry didn't help. I would lube it good b4 digging deeper. use actual oil like hoppes orange bottle or motor oil, not clp.....it doesnt have any viscosity

also yeah i never run reloads either

bohoki
02-22-2011, 11:49 PM
if the reloads were not trimmed

the acceptable max of a case length is 1.760 a chamber can probably handle 1.770

but ive measured sized cases that measure 1.774 and that can make the case pinch down into the bullet when chambered

i guess its like firing a12 ga 3 inch shell in a 2 3/4 it fits but bad things can happen

the only reloads i use are mine and i'm adequatly meticulous that i havent blown up a gun yet

but ive only loaded around 4-5 k of 223 so maybe i've just been lucky

AeroEngi
02-23-2011, 9:51 AM
Thank you all for the excellent feedback. I'll try using only factory new ammo and I'll keep her clean and well lubed.

mif_slim
02-23-2011, 9:58 AM
Yup, resizing the rounds could be the fault. You gotta over-cam the die setting for semi-autos, especially for AR and their tight tollerance. My SU shoots under-sized ammo just fine, but my AR does exactly the same as yours if I dont over-cam the dies. Once I did that, no issues in any of my reloads in any of my AR's.

Ian
02-23-2011, 10:29 AM
this happened to me twice with ammo bros reloads. it was a pain and a half to get the round out. shell looked dented somewhere too.

AeroEngi
02-23-2011, 11:36 AM
this happened to me twice with ammo bros reloads. it was a pain and a half to get the round out. shell looked dented somewhere too.

Ya, my cases looked a little dented and rather dirty. I'm glad to see that I'm not the only one with this problem. I'll definitely be shooting factory ammo from now on. I just ordered 1000 rounds of Federal XM193F from Palmetto last night! Can't wait to try them out...

Mr. Casull
02-23-2011, 11:47 AM
All reloaded ammo should be checked with a case gauge to make sure that they are sized correctly. Most likely the reloads you were shooting were not fully sized. I don't shoot anybodys reloads but my own so I know they meet the specs. Take one of the loads to a store that has reloading products and see if they will let you check some of the loads. They can tell you how the case should fit in the die.

Agustav
02-23-2011, 12:34 PM
Before we go any further about the reload as being the problem, I will first admit the reload is from me. I have been reloading for a few years now and never have problem with any of my reload for AR. The case was FL sized properly, and the same batch of reloads run flawlessly on the same day in my brand new 24" bull barrel AR. The brass might be on the long side (once fired), but definitely within spec (<1.760", checked each brass).

This incident did not happen immediately after we started shooting the reload. I would said we easily bang out a few mags before the bolt got stuck. When the bolt first started to get stuck, we had to bang the buttstock to get the bolt open. When the we retrieved the cartridge, the brass was extremely dirty. We attempted to clean the chamber as the best we can, and the rifle will fire off a few rounds before it's stuck again. I suspect the chamber was still not clean in combination with a brass in the upper range of tolerance is the culprit. I guess we'll find out more when we we hit up the range next time...

Just trying to set the record straight and protect my reloading ninja skill rep... =)

AeroEngi
02-23-2011, 12:39 PM
Before we go any further about the reload as being the problem, I will first admit the reload is from me. I have been reloading for a few years now and never have problem with any of my reload for AR. The case was FL sized properly, and the same batch of reloads run flawlessly on the same day in my brand new 24" bull barrel AR. The brass might be on the long side (once fired), but definitely within spec (<1.760", checked each brass).

This incident did not happen immediately after we started shooting the reload. I would said we easily bang out a few mags before the bolt got stuck. When the bolt first started to get stuck, we had to bang the buttstock to get the bolt open. When the we retrieved the cartridge, the brass was extremely dirty. We attempted to clean the chamber as the best we can, and the rifle will fire off a few rounds before it's stuck again. I suspect the chamber was still not clean in combination with a brass in the upper range of tolerance is the culprit. I guess we'll find out more when we we hit up the range next time...

Just trying to set the record straight and protect my reloading ninja skill rep... =)

You do have great reloading ninja skills (LOL) and I don't doubt that one bit. It did begin to fire the reloads after we thoroughly cleaned the chamber, bolt and lubed the bolt correctly. You even sprayed CLP inside the bolt and I think that with a combination of applying grease to the outside of the bolt did the trick. Thanks for your help bro!

NYY
02-23-2011, 4:55 PM
Ya, the mags were filled with 10 rounds. It was not the same ammo as the day before, I was using factory PMC bronze the day before and I was using reloads the day I was having problems.

PMC always works with mine too. Was probably the reloaded ammo

AeroEngi
02-23-2011, 6:13 PM
PMC always works with mine too. Was probably the reloaded ammo

and/or I did not know how to clean it. Considering that this is my first AR, I'm still learning... :)

rsrocket1
02-23-2011, 6:15 PM
See if you can pull the charge handle back and release it. The bolt should move smoothly and slide back easily without any binding or "slow" spots.

I would take the upper receiver off, clean the BCG and the insides of the upper receiver. You may see a lot of fouling there. Wipe it all around with a patch dampened with Hoppe's No.9 and see if you find any really dirty spots. Lube the friction points on the BCG.