apex M&P 5" barrel + acme 145gr bullet issue

[bun]

I recently installed a semi fit apex 5" barrel on my m&p 9L 
My go to load is a 145gr acme bullet 1.12 oal with no issues on my other 9s including the orig m&p barrel
The same load is tight in the apex 5" barrel and doesn't drop freely. tried to shoot 100 rounds and had 5 failure to eject and failure to go into battery. when I shorten the oal to 1.0 (which I don't want to do) it passes the plunk test
  No issues with the plated 147gr xtreme at 1.12 -1.14 oal or factory rounds (blazer 115, winchester, freedom munitions)
I know this has to do with bullet shape but what bullet do you guys use in your apex 5" ?

[Helios]

I use the 135gr TC from Blue Bullets loaded out to 1.14” in my Apex barrel’d M&P. The TC profile seems pretty forgiving with short throats. 

[kmanick]

Ibejihead 147

[bun]

I have thousands of acme 145s and I would have wanted it to work with my usual oal at 1.13.

max oal I've tested was 1.09 

I'll try the Ibejihead 147 and BB 135gr TC when I get a chance but for now I'll stick with the xtremes

[BJB]

18 minutes ago, bun said:

I have thousands of acme 145s and I would have wanted it to work with my usual oal at 1.13.

max oal I've tested was 1.09 

 

Just have your leade throated.

[GlockCanMan]

Bayou bullets 147gr. bullets should give you a little more play room. 

[MemphisMechanic]

I reamed the SDI barrel in my old M&P to take 147s out to 1.155” My load at 1.130”  (for all my guns) grouped nice and tight after it was throated.

 

I highly suggest sending the barrel to someone to get it cut for longer ammo, as the APEX barrels have short chambers. Several vendors can do it for you - Patriot Defense would be my recommendation.

 

Hell, I could do it if you like, but most people prefer sending a barrel to a known company.