Blown Primers Issue, Cured by Springfield-Armory

**L-2** · 03-03-20, 21:14

I bought a Springfield-Armory Saint, 5.56mm AR-15, 16" mid-length gas, MLOK free-float handguard, in 2018.
I shot 4,300 rounds through it in 2 years before figuring out something was wrong with the rifle.

Approximately 1+% of the rounds either blew out the primers completely or sometimes the extractor ripped off the case rim (usually with steel-cased ammo) instead of extracting. I later read the ripping off of the case rim was likely another indicator of over-pressure but I originally just thought it was the steel-cased ammo just getting stuck in the chamber, again, intermittently.

Springfield-Armory's customer service was very good, once I called them. They said no primers should be blowing out and I received a FEDEX return label right after the call ended. S-A's email said it could take 2-4 weeks. On the 4th week, I got a call from S-A who told me the AR-15 was being returned after the warranty repair.

The S-A rep. I spoke with said the chamber was reamed and the bolt carrier group was replaced. He said the notes don't provide any findings other than what was done. He said in all the repairs which he's seen over the years he's maybe only seen one other AR-15 needing this type of work at S-A.

Today, after receiving the AR15, I put 820 rounds through the rifle with zero failures using three types of ammo (Federal XM193 55gr.; PMC 5.56 green tip, don't recall bullet weight; and PMC .223 55 gr.).

I'm just wondering what the experts here might think what the problem was with my rifle as S-A's policy apparently is to only say what they've done, but not why.

My experience is just being an LE user (we used older-school Colt AR15s at my department) for ~20 years before retiring and I've not previously come across this problem nor have any of my immediate friends.

**Dennis** · 03-03-20, 22:02

This is a common issue with many not-so-tightly spec'd manufacturers and shooting 5.56 in 223 chambers.

See the description for this tool. I have used it successfully many times. It has even removed some chrome on Colt chambers as not everything can be perfect.

Click on the "5.56 Reamer"
http://www.m-guns.com/tools.php

Dennis.

**L-2** · 03-03-20, 22:56

Wow. Thanks for the link which seems to describe what Springfield-Armory determined & needed to be done.

I'm glad Springfield-Armory's warranty/customer-service folks figured that out (and had the tool to do the job). I'm also glad Springfield-Armory's warranty department has a good reputation. However, in the future, should I ever buy another AR-15 (I've also got a Bravo Company), I'll not hesitate to spend more for one of the recommended companies found here on M4Carbine.net, hopefully to not need to go through a warranty-repair-issue.

I'll probably never know why they needed to replace the bolt carrier group (BCG). I wonder if there are any common problems with off-the-shelf production BCGs.

**rjacobs** · 03-04-20, 08:36

Originally Posted by L-2

I'll probably never know why they needed to replace the bolt carrier group (BCG). I wonder if there are any common problems with off-the-shelf production BCGs.

If you had a bunch of blown primers there could have been pitting on the bolt face.

**ChazC93** · 03-05-20, 08:35

Replacing the BCG is a good move. If it worked with the previously out-of-spec barrel, there is a good chance you'll have issues with the new in-spec barrel.

Also the blown primers could have caused excess or non-standard wear on the bolt face.

Good to hear they fixed this mistake. Stuff happens. Just nice to see how they reacted.

**BFS** · 03-05-20, 09:58

Howd they ream a Nitride coated chamber?

Ned has stated before that Nitride usually chews up his reamer.

**markm** · 03-05-20, 11:32

Originally Posted by L-2

Today, after receiving the AR15, I put 820 rounds through the rifle

Holy Smoke!

**Humpy70** · 03-13-20, 06:37

I am not following exactly what was done here. I tried to open the "reamer" block but nothing happened. Have you got any pics of the blown primers? Also pics of rounds that primers did not blow?

**L-2** · 03-13-20, 11:59

Attachment 61319
Blow primer pic, as requested.

For Post 8, goto Post 2, click on the link; then click on "5.56 Reamer" in the link; more information on the 5.56 Reamer product will then be visible to read.

I've no pictures of cases with unblown primers and will not be able to get any as my Springfield Saint is now deemed cured and no pics were taken of unblown primered cases. I will say some unblown primered cases had chunks ripped out from the rim when cases failed to extract. At that time, my knowledge just thought that was bad ammo/cases, and I didn't equate that problem to an over-pressure/early-unlocking problem. I've now learned more about what could go wrong with an AR-15, even from a brand-name company like Springfield-Armory.

A larger company, such as Springfield, might be buying hundreds, if not thousands of barrels. 100% of these barrels may not have perfectly made/reamed chambers/leades resulting in my intermittent over-pressure issues. Further, I suspect not all customers will even bother to send in their AR-15s as I didn't for 2 years, not immediately recognizing this as a gun-problem. I could have merely just transitioned to only shooting .223, instead of 5.56, and lived out my life and the life of the rifle, not knowing any better.

I tend to shoot a lot at 5K+ rounds in 2 years through just this firearm (which is less than some folks, but more than others). A thousand rounds/week is common for me. I also seem to be "that-guy" who is likely to encounter a gun problem, which is just my luck (I've had 4 Glock frames replaced over the years due to frame failures).