Popping primers issue?

[u/Nick_Youngs_7th_wife]

Took the new WLVRN to the range for the second time. My previous/first trip was just a function test using PMC 55gr 5.56 so I could dial in the gas; no discernible issues at that time besides occasionally not feeding the first round from a magazine (which I attribute to user error). This trip was meant to zero on my preferred 68gr 5.56, which I got from Nautilus Ammunition (cheaper enough than Hornady Frontier to justify checking them out. I previously had no issues running 500+ rounds of this stuff through my AR-15.

First issue I noticed on this trip: after firing the first shot, gas was leaking out of every orifice of this gun despite that my suppressor is a LBP/flowthrough style. I attributed this to slight over-gassing because I had it set up for the lighter 55gr stuff; I did not initially adjust to a lower setting because I want the gun to run on lower-power cheap ammo.

I continued to test with the 68gr and got a decent 5-shot group at 25, so I moved up to 75 (which was the distance I planned to zero at). Started having wild malfunctions. Bolt would get stuck in the forward position, then in the rear position, then would fail to extract, then would fail to go into battery. I had to pseudo-mortar the gun (can't mortar at this indoor range) to get at least two rounds out of battery or the bolt to move. Accuracy had also gone to shit all of a sudden. I cranked down the gas setting but the issues persisted.

I considered packing up and going home, but after the gun cooled I worked the action a few times and it functioned normally and would go fully into battery. So I tested again with 55gr PMC and it was working totally fine again. I looked at the spent cases of my 68gr and found that the primers popped out of two of them; I found the primers nearby. When I got home, I found 2 more inside the gun, one was fully punctured; part of a primer got lodged under the trigger pack, would you believe, while the rest were hiding in the butt cavity. There was no obvious damage to the bolt, carrier, feeding ramp, or rifling.

The weight of the evidence points to this being an ammunition issue and that's what I get for buying a goofy grain weight from a boutique ammo manufacturer. I never had this issue with my AR, but it's still probable that the batch I was testing through the WLVRN just happened to be a bad one.

I'm posting all this to ask: has anyone else had issues with a 2025 or onwards WLVRN popping primers on certain ammunition? I want to rule out that this is a combined gun+ammo issue or just a gun issue because it's much easier for me to just buy different ammo.

[u/FrozenIceman]

What gas regulator settings did you use unsuppressed and surpressed?

How did you set your initial regulator settings?

A reminder, a flow through suppressor still increases pressure to the bolt. If you were already over gassed unsuppressed it will be more rough suppressed even with a flow through.

How many rounds are through the gun? The MDRx needed about 500 rounds through it to wear everything in and then it would need less gas to function.

[u/Nick_Youngs_7th_wife → u/FrozenIceman]

What gas regulator settings did you use unsuppressed and surpressed?

3 or 4 clicks in on suppressed with 55gr. Haven't shot unsuppressed.

How did you set your initial regulator settings?

Cranked it all the way down and then increased until I got BHO on 55gr suppressed.

How many rounds are through the gun?

Not enough to be broken in. But I am skeptical that breaking would reduce a primer-popping issue. I did notice that after my experiments with 68gr that I was able to lower the gas regular for 55gr by one click, so I may have mistakenly broken it in faster than otherwise for better or worse

[u/FrozenIceman → u/Nick_Youngs_7th_wife]

I think 3 or 4 clips should be around the normal setting, so you shouldn't (TM) see primer issues with the flow through. I would try it unsuppressed and see if you have the same issues, then click the regulator one and 2 steps down to see if you still get BHO and inspect the primers.

Once you isolate the issue to the Unsuppressed vs Suppressed and what settings (make sure to record the marking on the regulator) did what give their warranty a call and see if they have any advice for you.

[u/Nick_Youngs_7th_wife → u/FrozenIceman]

Do you think it's unwise to have it set for 55gr and then shoot heavier projectiles through it? seems like the gas was wildly more intense between the two on the same setting.

[u/FrozenIceman → u/Nick_Youngs_7th_wife]

I think that you should be able to have a setting that operates both fine. When it comes to gas pressure both rounds should (TM) be loaded to the same chamber pressure. The only real difference should be if a manufacturer loads one much lighter (such as low velocity ammo or reloads by people who are shaving costs on powder) than the other in which you might get a failure to lock back if your gas setting isn't higher.

If the gas settings are wild, that might be an indication the regulator was drilled improperly, may want to remove and inspect the plug holes (also check to see if the regulator is stamped with the correct regulator code for your caliber and barrel length, see your manual for the decoder).

Note: Some boutique manufacturers may load their ammo above SAAMI, I.E. hotter than most would consider safe. If this is the case, that might be what is causing the popped primers like you suspect.

[u/Master-Blaster42]

Ive got an old MDRx and I cant use Fiocchi 5.56, it puncturws the primer and then I have to dissasemble the gun to find the damn piece. It sucks but when PMC Bronze shoots so softly that the muzzle doesn't move I figure its an even trade off.

[u/FrozenIceman → u/Master-Blaster42]

That doesn't sound normal, you should probably give DT warranty a call.