deformed brass

[generalpetres]

went to the range today break in my new ar, when i was having randall install the barrel the headspacing was tight and wouldnt close on a go gauge. any way i was having some Failure to feed problems where the round would go in half way then it seems the bolt would slide over the cartridge hitting the round mid case causing a jam.

ontop of that my brass necks are being dented, there coming out in the shapde of a D. i only had a little time at the range as they were closing so i wasent able adjust my gas block.

wmd guns nib-x upper
wmd full auto nib-x bolt
AR15 Performance 20" spr 223wylde barrel
adjustable gas block
lancer carbon fiber handguards
rifle length gas system

[bodiebill]

deformed brass

Take it back to Randall and have have him correct the headspace--most critical step of assembly!

For reloads that jam, use a small base die when resizing.
If new brass then you might have a camber or headspace problem.

For dented brass at the neck you can use a round shank phillips head screwdriver to form and straighten the opening before resizing. Position the end of the screwdriver in the primer hole and rotate the shank against the dent.

[kcstott]

I think he's more concerned with why it's denting then how to fix the dent.

OP you own a rifle that was designed for a battle field. No one picks up brass on a battle field. I bet your brass is being dented as it hits part of the weapon on the way out.

[BSlacker]

the headspacing was tight and wouldnt close on a go gauge.

This is not a good condition to be firing the rifle in.

Failure to feed problems where the round would go in half way then it seems the bolt would slide over the cartridge hitting the round mid case causing a jam.

Most likely the headspace issue has nothing to do with the FTF issue. If the bolt hits the cartridge mid case then it did not go far enough to be an issue of jamming from a headspace issue. Most likely a mag issue. At a minimum I would full length resize and small base if I had any chambered rounds stick. If the rounds don't make it to the chamber, bolt over runs cartridge, it most likely isn't a resize issue.

my brass necks are being dented, there coming out in the shapde of a D.

If the neck is bent smooth then when it enters the die it will encounter a neck sizing button. It will make the neck work in the sizing portion at the top of the die and makes the final neck size on the cartridge on the way down and out of the die. Run one through the die before doing any extra steps to relieve the D shape. You have to much ejection force.

[tujungatoes]

OMG an AR that had headspace problems!?!? But....I thought they were all "mil-spec" and cool and you don't even have to check headspace.

Ok seriously though.
1. Whats up with the tight headspace? If it wouldn't close on the go gauge then you shouldn't be shooting it. That sh*t is dangerous.
2. The bolt riding over the round sounds like a magazine(or mag height) issue. Once you get the headspace issue sorted try some different brand mags and see if there's one you rifle likes better. If not then start modifying stuff.
3. Case necks that get dinged to a D shape are really no big deal. You may be able to lessen that by tweaking the gas system, but it may not go away entirely. Like BSlacker said, it'll get ironed out in the resizing die. No worries.

[generalpetres]

redoing the headspace is going to be a pita as the barrel was coated in melonite. ill message randall again to see what he says and ill also message ar15 performance as well. even though the headspacing is tight i can still get the bolt to close on a round and out of the 40 rounds i put thru the rifle i was only having issues with the jams.

when the bolt closes on a round it takes a bit of effort to get the round out when trying to open the bolt via charging handle.

as for the d shaped neck rounds, im only concerned as i would rather fix the issue vs just fixing the dented rounds, i wasent able to dial in the gas system as the range was closing. im going to be getting a reloading set up soon.

[tujungatoes]

Without some extreme measures there is no fixing HS on an AR. Randall will tell you to use a different bolt.

Once you get the HS sorted head back to the range and tweak on the gas system to see if you can help keep the necks from getting dinged as bad. Keep in mind though, it may be something you end up having to live with. Also congrats on getting into reloading.

[Rangem4]

The high end barrels usually come with a match grade bolt.
Meaning the head space and barrel bushing measurements are perfect.

[generalpetres]

The bolt is a wmd guns nibx coated bolt.

[generalpetres]

The bolt is a wmd guns nibx coated bolt. Being the bolt ls coated in nickel boron. Do you think that added thickness is making the headspace very tight. If I try and close the bolt by hand I have to use the forward assist to get into battery but if I racket it and let it go it closes in a round its just tight to get the bolt pulled open

[Gunsmith Dan]

OMG you never never never NEVER EVER want to fire a rifle that does not close on a GO gauge ........ unless you have a large life insurance policy and your wife likes to buy $400 pairs of shoes every day .... then go ahead.

Certain low pressure pistol cartridges you can get away with not closing on a GO gauge but NOT high pressure rifle rounds. IF the round sits to far back the case is not supported and can rupture sending hot gas into your magazine set off all the rounds in your magazine.

There is a REASON for using the gauges and not just use the gauge then ignore the results.

IF the GO gauge will not fully insert into the barrel to allow the bolt to close over it BUT the bolt with the GO gauge removed fully closes and locks then most likely your barrel chamber was not reamed to the proper depth.

If your bolt with nothing in the chamber does not fully close and lock then either the barrel is to long in the rear between the chamber the ring, or your bolt is to long.

[BSlacker]

My question for the OP is. Did you remove the extractor during the headspace measurement?

The AR15 is an amazing device. If the bolt doesn't rotate to lock in the barrel extension, such as it would if the bolt didn't rotate closed on a GO gauge, a proper AR15 firing pin will not contact the primer with sufficient force to fire the round. So not closing on a GO gauge is bad but if true would most likely not result in ignition when attemping to fire, if the headspace were short. Most likely the measurement was a little off and headspace is just tight. It chambered and fired some 40 rounds of factory ammo.
The hard extraction, of a unfired round, could be the result of short headspace making the lock up tight. Remove the bolt and carrier and drop a factory round in the chamber make sure it goes in all the way and then turn it so it should drop out. A small tap on the rear of the upper should make it fall. Otherwise your chamber is tight as well.

[generalpetres]

the barrel is chambered in 223 wylde. when i insert a unfired factory round in the chamber it goes right in and slides right out with ease, ill take a pic of both my ars with rounds in the chamber to compare the 2. im thinking the head space is fine its just tight due to the melonite coating on the barrel and the nickel boron coating on the bolt.

i measured the lugs on the bolts and on my chrome young mfg bcg the lugs are .277in thick where on my nickel boron bolt the lugs .278in thick. so i think its just the coating causing the bolt to be a bit tighter.

this is a picture of my other ar as an example:

here is a round in my new ar barrel as you can see they look both the same:


when randall was putting the go gauge in he tried closing it by hand with the extractor still on the bolt.

[BSlacker]

tried closing it by hand with the extractor still on the bolt.

Some makes of gauge will want to have the ejector and extractor removed for a precision check on a tight chamber bolt combo. For a quick check one can leave them in but if it fails by a small amount like yours then try again after the parts are removed. If it fails then work it out don't be shooting it. It's not worth it.

[generalpetres]

problem is its an hour drive to have randall check the bolt as i dont have an go gauge.
i removed the extractor and put a round in the chamber and used a punch to keep the bolt all lined up, i was able to close the bolt on the round with ease, i have an extra power extractor spring installed on my bolt which might be the reason its a bit tough. what are your guys thoughts

i would show removing the bolt but its kinda hard holding the upper receiver and film with my other hand at the same time.