AR10 BCG won't go into battery

[czerr3@gmail.com]

After 1st round firing, bcg ejects 1st round and strips and loads 2nd round. However bolt doesn't go fully into battery. About a 16th if an inch from full battery.

I've changed buffers and buffer springs multiple times. Changed BCG to a NiB one.

Started with Gene3 PMAGS, than to AR Stoner brand, Hexmag and metal Mil-Spec mags.

Still a no go.

Upper and lower are both Aero.

Can't figure what to try next. 

[edgecrusher]

How wet? These rifles take quite a few rds to break in and like/need to be dripping wet. Also, have you checked head space? 

[czerr3@gmail.com]

Have run only about 50 rounds due to pure frustration after all the attempts to resolve the failure of the 2nd round to fully seat and lock in the bcg completely.

Have not confirmed headspace so may need to be the next step.

[czerr3@gmail.com]

Steel barrel nut for a free-float handguard.

 

[czerr3@gmail.com]

Racking the bcg for 1st round seats perfectly.

Only the 2nd round gets picked up and moves into the chamber but not far enough to lock in.

Could it be the mags?

[unforgiven]

Try another mag brother

[czerr3@gmail.com]

Tried Pmags, AR Stoner, Hexmag, ASC.

Any other type suggestions?

[edgecrusher]

How wet is it. Also please check headspace 

[czerr3@gmail.com]

Sorry for my ignorant what are you indicating by "Wet" ?

And had to order a new HS field gauge on Miday, will arrive Tuesdsy.

[98Z5V]

Describe all the details of your recoil system.  It's your recoil system, or you are under-gassed.  Hard to tell with the limited details of your gun.

Edited November 16, 2020 by 98Z5V

[98Z5V]

2 hours ago, czerr3@gmail.com said:

Sorry for my ignorant what are you indicating by "Wet" ?

 

THIS wet...

[czerr3@gmail.com]

Rifle Length gas tube with a YHM Gas Block.

20" Faxon Barrel.

Geissele flat spring AR10 buffer spring.

Aero AR10 Buffer. Fail Zero NiB BCG.

I don't think its under gassed as it completely ejects the 1st round, picks up and seats 2nd round. It simply doesn't lock down the bcg the final 1/16".

If I load and shoot only 1 round, it fires, ejects and locks open the receiver.

So I'm thinking not heavy enough ammo or the mags are slightly rubbing my bcg.

[czerr3@gmail.com]

Oh and @98Z5V 

No its not Wet. Its adequately lubed as I do all my other firearms just not over done and sopping wet.

[edgecrusher]

58 minutes ago, czerr3@gmail.com said:

Oh and @98Z5V 

No its not Wet. Its adequately lubed as I do all my other firearms just not over done and sopping wet.

 

6 hours ago, edgecrusher said:

How wet? These rifles take quite a few rds to break in and like/need to be dripping wet. Also, have you checked head space? 

Well that could be an issue. That’s why it was stated. They need a lot more lube than an AR 15. Could you measure you buffer and weigh it? Also the internal depth of your receiver extension and relaxed length of your spring. And please measure the size of your gas port

[czerr3@gmail.com]

Thx a lot for the lube advice. Ill be sure to soak it down next outting.

Will get the suggested measurements back here during the week.

[98Z5V]

2 hours ago, czerr3@gmail.com said:

Rifle Length gas tube with a YHM Gas Block.

20" Faxon Barrel.

Geissele flat spring AR10 buffer spring.

Aero AR10 Buffer. Fail Zero NiB BCG.

I don't think its under gassed as it completely ejects the 1st round, picks up and seats 2nd round. It simply doesn't lock down the bcg the final 1/16".

If I load and shoot only 1 round, it fires, ejects and locks open the receiver.

So I'm thinking not heavy enough ammo or the mags are slightly rubbing my bcg.

1st.  Gelssele doesn't make a spring for a .308AR, at all, and of the springs that they do make, they're not flat springs - they're braided wire. 

Aero AR10 buffer - okay...   Rifle buffer or Carbine buffer?  Rifle recoil system or Carbine recoil system here?  Who made the receiver extension, and what's the internal depth of that receiver extension?

Where does the gas tube end, inside the upper receiver?  Should be directly in the center of the cam pin cutout that's in the upper.

Since ammo came up - what ammo are you shooting?

Read this thread here, thoroughly.  You haven't provided near enough information, on your own, and barely what we've asked.  Read this thread, so you get an idea of the kind of info that we need. 

 

Edited November 16, 2020 by 98Z5V

[98Z5V]

It's Cristmas Eve, and I'm feeling Grinch-ish.  Let's get this moved out of this section, that is for information, and get this guy's QUESTION moved to the build section, of something - it doesn't belong here, in this section.