Bolt carrier group won't go back

[Calgunner0503]

Hey guys, new to Calguns.

I'm working on an AR build currently and with my upper receiver in place, I cannot for the life of me make the bcg clear the ejection port. I can pull on the charging handle enough to make the bcg go back about 3/4 of the way, but it will not go all the way back. That being said, I can't lock the bolt back or chamber a round(when the time comes).

Here is my list of parts:
-80percentarms 7075 aluminum lower
-Palmetto State takedown pins/bolt catch/selector/buffer tube assembly
-Hiperfire Hipertouch EDT using the 4 1/2lb spring
-Mission first tactical pistol grip
-Mission First Tactical Minimalist stock
-Surplus Ammo and Arms 7075 stripped upper
-Surplus Ammo and Arms nitride BCG
-Surplus Ammo and Arms charging handle
-Primary Arms 16" mid-length barrel 1/7 twist, SOCOM contour
-Daniel Defense mid-length gas tube
-SLR Rifleworks adjustable gas block
-SLR Rifleworks 15" SOLO series MLOK handguard
-1/2x28 muzzle brake [forgot brand(sorry)]

Any help is really appreciated, I can try to post pictures if it helps.

[LeadFarmer74]

Upper receiver works when it is not on the lower? Does the bcg move freely when the upper is off the lower? Does the buffer and spring move freely?

[Calgunner0503]

Upper works just fine when the receivers are separated. Charging handle and bcg move in and out perfectly. It's seems like the buffer and spring move fine too. I don't have problems joining the receivers either. It feels like I'm catching on something, but I can't tell what it is.

[LeadFarmer74]

Pictures would help at this point. You can push the buffer and spring all the way in?

[Pardini]

Charging handle is catching on the end plate.

[strongpoint]

You're not using a rifle buffer and/or spring in a carbine buffer tube, are you?

[Jon Road King]

With the receiver off, does the hammer lock back?

Sometimes those 80% jobs don't get the front corners of the fire control pocket machined far enough forward and the hammer won't cock, which drags on the BCG.

[Calgunner0503]

Sorry, don't really know how to reply to individual posts.

My charging handle clears the receiver end plate with ease.

I'm using a carbine buffer and carbine buffer spring in a milspec carbine buffer tube

My hammer locks back with the upper on and off.

I'm stumped.

[Bishop98]

Sorry, don't really know how to reply to individual posts.

My charging handle clears the receiver end plate with ease.

I'm using a carbine buffer and carbine buffer spring in a milspec carbine buffer tube

My hammer locks back with the upper on and off.

I'm stumped.

Use the Quote+ button on the posts you wish to answer.

[Calgunner0503]

Use the Quote+ button on the posts you wish to answer.

Thank you.

[baih777]

you need to take it apart and look for the shiny spot .

[xfer42]

You're not using a rifle buffer and/or spring in a carbine buffer tube, are you?

My money is on this ^

[baih777]

if no marks, post the length of your buffer and spring.
sounds like wrong spring.

[Calgunner0503]

if no marks, post the length of your buffer and spring.
sounds like wrong spring.

Buffer spring is 10 3/4" long
Buffer is 3 1/4" long

It was advertised as carbine buffer and buffer spring. Did I receive something wrong??

[ar15barrels]

This type of troubleshooting is best done in person.
The problem will be very easy to see when someone knowledgeable looks at it.
Since everyone else is just guessing, I am going to guess that the bore of the upper is not inline with the buffer tube and that the bolt carrier is striking the edge of the buffer tube.