Having trouble getting my rifle to cycle a new round, and occasionally eject the casing.

Grandfather impulse bought a PSA compete AR one day and decided he didn’t want it. So he gave it to me, and it was my intention to upgrade it. Took it out one time and it would not cycle a new round, and sometimes wouldn’t eject the spent casing. The bolt would not lock to the rear on the last round.

Talked to some of my friends who know more than I do and they thought it might be under gassed. So I upgraded the upper, which I was planning on doing anyway.

Specs for new upper:
Upper: TNTE 7075-T6 Forged M4 Upper. We use Cardinal, Anchor Harvey, and Performance Forge.
Barrel: BA Hanson 5.56 13.7 1/7 4150 with QPQ finish with 1/2x28
Gas System: Carbine
Gas Port size: .070
Gas Block: Pinned on Low Profile
Handguard: MI 12.625 Combat QuadRail
Flash Hider: Surefire Warcomp pinned and welded

Slapped it on the PSA lower, with the PSA bcg and charging handle and took it back out last night. Same issues. Checked the buffer, the spring is just over 10.5in and the buffer weighs 3.00oz.

I’m at a loss now, only thing I can think would be to change the bcg out. Which, again, I was going to do anyway. But I was planning on doing all of this in stages not one weekend.

Ammo? Try good quality M193 or M855 and report back.

What ammo?
Also, check your gas key on the BCG to be sure that it is tight and not leaking gas, check YT for instructions.

Using Winchester M855

I just went through this with a buddy of mine who got a used AR from GunBroker.

TNTE is not an upgrade.

What does the fired brass look like? Any rough sections on the case exterior?

Does unfired ammo eject easily when you pull the charging handle?

What magazines are you using?

Are you keeping the BCG well lubed?

How far does the gas tube enter the upper receiver?

When you have the bolt locked open on an empty magazine, how much farther can you get the BCG to move to the rear?

The problem was most likely with your BCG or the gas block's seal on your existing barrel.  
.070 is a poor port size for a carbine gas 13.7".  We use .068" on our 12.5" and you can get away with less.  This has another inch of dwell time, + a bigger port.

Warcomp's are really suited to 13.9" barrels... you either have an huge shim stack, or it's still < 16" OAL.

I expect a good BCG would get your old upper to run, but the current upper you described above is likely overgassed.  You'd be well served using a BRT gas tube in that thing around .063-.064" or so.  .0625" is milspec on a 14.5" carbine gas system, so it shouldn't need to open up much from there, if any at all.

Chamber a spent case and blow into the barrel. Gas leak should be too small to detect.