bolt not staying locked back?

[Travelingchild]

1. S&W lower receiver locally purchased, LPK from G & R,
Magpul grip, milspec. ctr stock,receiver extension, buffer& spring from Larue tactical.
I assemble that myself.

2. Colt Upper with with 14.5 light weight middy DD barrel with dpms gas tube with troy low profile gas block & permed vortex flash suppressor & Troy 13 inch trx rail
Assembled & tested by Ambush Tactical Boise Idaho on one of their lowers.

Recieved upper & attached to my lower, & mounted a Vortex HS 1x4 on a adm mount.

Ran 60 rounds of ae 55 gr.tactical at 25 yrd, functioned fine, while sighting in scope.
Ran some tula steel cased failed to extract 1st two rounds, oiled it more, ran total of 60 rds no further issues.
Outside temps about 25 degrees

Bolt locks back on empty mags, GI, MagPul, or Lancer.

But If I bump or adjust the stock It goes forward by itself.

Is it possible I assembled the bolt catch incorrectly? IS that even possible?
Spring, Buffer, Bolt catch, Roll pin?

[Iraqgunz]

How hard are you bumping it? It doesn't take much to make it go forward. As for the malfunction, chalk it up to Tula ammo.


1. S&W lower receiver locally purchased, LPK from G & R,
Magpul grip, milspec. ctr stock,receiver extension, buffer& spring from Larue tactical.
I assemble that myself.

2. Colt Upper with with 14.5 light weight middy DD barrel with dpms gas tube with troy low profile gas block & permed vortex flash suppressor & Troy 13 inch trx rail
Assembled & tested by Ambush Tactical Boise Idaho on one of their lowers.

Recieved upper & attached to my lower, & mounted a Vortex HS 1x4 on a adm mount.

Ran 60 rounds of ae 55 gr.tactical at 25 yrd, functioned fine, while sighting in scope.
Ran some tula steel cased failed to extract 1st two rounds, oiled it more, ran total of 60 rds no further issues.
Outside temps about 25 degrees

Bolt locks back on empty mags, GI, MagPul, or Lancer.

But If I bump or adjust the stock It goes forward by itself.

Is it possible I assembled the bolt catch incorrectly? IS that even possible?
Spring, Buffer, Bolt catch, Roll pin?

[kmrtnsn]

I don't know what your experience level is with the AR platform but bumping the rifle and having the bolt autoforward is normal. The question is, how hard are you bumping it to make this happen? If it is the slightest touch then your bolt catch may not be engaging all the way, as in it is only coming up a fraction of its range.

to check the bolt catch, remove the lower from the upper and insert one each loaded (it just takes a couple-three of rounds in the mag to push the follower out of reach) and an unloaded magazine of each type to visually check the travel and return of the bolt catch. After inserting each mag, hit the mag release and see if the catch lowers on its own.

Several other factors could be at play here if the catch functions normally. Try this first to localize and go from there.

[Travelingchild]

How hard are you bumping it?

Stock extended or collapsed, I hold it about 2 inches off the floor & let gravity take it, Or if I adjust the CTR stock forcefully.

Daniel Defense Bolt carrier group I forgot to list.
This is with the magazine out. I just tried it with my 1st ar-15 Colt HBAR Match with fixed stock Does the same thing.
I'm guessing it's normal as weapon functions fine.


I don't know what your experience level is with the AR platform but bumping the rifle and having the bolt autoforward is normal. The question is, how hard are you bumping it to make this happen?

Minimal 1st build with regards to lower, don't have the tools or knowledge to headspace an upper so I had it professionally done.
I'll continue with you suggestions as I put more time on the weapon

Thank you

[markm]

But If I bump or adjust the stock It goes forward by itself.

Is it possible I assembled the bolt catch incorrectly? IS that even possible?
Spring, Buffer, Bolt catch, Roll pin?

Shouldn't drop on a stock adjustment.

Yes. It's possible to assemble the bolt catch/plunger/spring incorrectly. It's also possible the catch isn't moving freely due to a number of things....

rough/high spots in the lower/finish in the catch slot.... weak spring, rough/high spots in the plunger hole. You need to look at a functional rifle to compare against the movement and tension of your catch.