M4 light strikes with Truball Slugs!

[Grapeshot]

Looking for some help:

Ive got an m4 with about 1k thru it. I’ve noticed lately I’ve been getting quite a few light strikes with federal’s non-le tru ball slugs, the 1600 fps ones.

 

this has happened 3 range trips in a row, this one being the most aggravating -

Today I had 2 of 10 shells that took 3 hammer falls before they would ignite, and I had one shell fail to return to battery, got stuck right in the mouth of the chamber. A tap of the bolt handle and it closed.
 

Is it just bad batch at the local fleet farm? Called benelli and they said it’s likely the ammo. 

 

I did notice primers are a different color, more of a maroon, on the non-le Truball slugs, vs a brass color on the LE ones and buckshot.
 

Spent case primer indents on the fired cases look a bit shallower vs the LE slugs, along with all the other ammo I’ve tried. The shells that fired on the third trigger pull the primers backed out slightly under recoil.
 

No issues with anything else, it seems isolated to this specific line. I didn’t think to photograph batch numbers from the boxes, in hindsight I wish I did. 
 

Not one light strike or failure to feed with LE Truball slugs, 8 or 9 pellet flight control buckshot, Brenneke slugs, Winchester buckshot, plenty of Winchester and federal birdshot down the pipe with no issues, etc. 

 

Any thoughts? I clean the shotgun and the bolt group each time I shoot. Lube is slip2000. 

Modifications - carrier comp tube spring and follower, shooting sight hammer, FTT handguards

Edited September 9, 2025 by Grapeshot

[remarkable]

Ensure to inside of your bolt head is clean, more specifically where the firing pin travels through the bolt.  Worked on many Benelli's with a lot of debris in tghis area which caused light strikes.