Lancer AR Mags and Overgassed-like Condition?

[RaceFan]

During the ammo experiment the other day, I also took the opportunity to function test several types of factory-style AR mags in my trove. Each mag was loaded with 25 rounds of 55 grain Fiocchi 223 for this trial.

• PMag Gen2
• D&H (aluminum) from Palmetto
• Lancer (dark smoke color in case anyone was wondering)
• C Products (stainless steel)

For reference, I was running a 1:8 twist, 18-inch fluted stainless with a Tanker compensator from Mid State Firearms. The buttstock is a Magpul UBR Gen2 fitted with an H2 buffer that addressed an overgassed condition from earlier.

Except for the Lancer mag, the rifle performed normally, ejecting the empty cartridges at between 4 and 5 o'clock out at least 10 feet. The empty shells from the Lancer mag discharged at between 1 and 2 o'clock, and landed about 5 feet away, simulating an overgassed condition. The empty casings flew out of the non-Lancer mags like a stick flipping in the air when playing catch with your dog. The Lancer exit and velocities replicated an underhand softball pitch.

Same rifle. Same ammo. Anyone know why the Lancer performed like it did? Not bashing the mag, just curious if anyone knows the potential cause. The only difference I see is the extra hole on the Lancer's anti-tilt follower.

Thanks.

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[hatchj]

I dint know, but those same lancer mags are the only ones that have ever been in my rifle when I've had a malfunction.

 

[oli700]

I understand you seen the problem with the lancer in. I can see all kinds of issues a mag can cause but for the life of me I do not put together how a mag can affect extraction/ejection . Feeding into the chamber yes , extracting from the chamber , I can't see the correlation between mag and ejection pattern .

 

[titsonritz]

Just a wild guess, weaker mag spring applying less upward pressure to the BCG allowing to it slip by faster due to less drag.

 

[RaceFan]

Looked on youtube and condition I experienced/saw with the Lancer mag is actually UNDERgassed. Sorry for the confusion.

But, the question remains: how the heck does a mag change the gas operations? I cannot figure out either.

I will try to hit the range again this weekend and photo the pattern. This is definitely a head-scratcher.

 

[Stomper]

Do the Lancer mag-springs feel stiffer or mushier compared to the others while loading them?

 

[RaceFan]

Do the Lancer mag-springs feel stiffer or mushier compared to the others while loading them?

Lancer feels stiffer, and...

Completely unscientific, but resting a weighted object with a taped ruler to see...

• PMag Gen2: ~3.75 inch drop
  
• D&H (aluminum) from Palmetto: ~3.25 inch drop
  
• Lancer (dark smoke color in case anyone was wondering): ~2.75 inch drop
  
• C Products (stainless steel): ~3.25 in drop

Just don't know... perhaps what @titsonritz referenced above???

 

[Geardo]

Seems like stiffer spring + rougher finish on the feed lips is slowing down your BCG. Maybe polish up the fees lips a little on the lancers, or use em in a different gun, or sell them to me for cheap?

 

[Jcon268]

During the ammo experiment the other day, I also took the opportunity to function test several types of factory-style AR mags in my trove. Each mag was loaded with 25 rounds of 55 grain Fiocchi 223 for this trial.

• PMag Gen2
• D&H (aluminum) from Palmetto
• Lancer (dark smoke color in case anyone was wondering)
• C Products (stainless steel)

For reference, I was running a 1:8 twist, 18-inch fluted stainless with a Tanker compensator from Mid State Firearms. The buttstock is a Magpul UBR Gen2 fitted with an H2 buffer that addressed an overgassed condition from earlier.

Except for the Lancer mag, the rifle performed normally, ejecting the empty cartridges at between 4 and 5 o'clock out at least 10 feet. The empty shells from the Lancer mag discharged at between 1 and 2 o'clock, and landed about 5 feet away, simulating an overgassed condition. The empty casings flew out of the non-Lancer mags like a stick flipping in the air when playing catch with your dog. The Lancer exit and velocities replicated an underhand softball pitch.

Same rifle. Same ammo. Anyone know why the Lancer performed like it did? Not bashing the mag, just curious if anyone knows the potential cause. The only difference I see is the extra hole on the Lancer's anti-tilt follower.

Thanks.

View attachment 550516
View attachment 550517

Interesting because I've noticed my Lancers seem to eject the casings in a more rearward fashion than my USGI style mags (Okay, BCM, PSA)....strange!

 

[Brian Vedack]

The added spring tension would add drag to the bcg.(ie-pushing the bcg upward in the upper. Binding of the bolt in the extension due to misalignment.) Could the mag sit too far in the mag well? Any wear marks on the feed lips?

 

[oli700]

Testing the theory of the spring , can you remember if the shells were landing all in one area ? Assuming your ammo isn't too inconsistent the shells should be landing in the same general area , if the gun is tuned good you chould land them all in a bucket . If the mag spring pressure on the carrier affected the carrier speed then the ejection pattern would be from 4 to 1o'clock as the spring unloaded ...as the pressure would lessen as the magazine unloads from firing ...... in my mind. Then it would be a common problem and common knowledge. Lancer to me is the end all be all magazine so it's hard to pin this one down

 

[RaceFan]

Testing the theory of the spring , can you remember if the shells were landing all in one area ? Assuming your ammo isn't too inconsistent the shells should be landing in the same general area , if the gun is tuned good you chould land them all in a bucket . If the mag spring pressure on the carrier affected the carrier speed then the ejection pattern would be from 4 to 1o'clock as the spring unloaded ...as the pressure would lessen as the magazine unloads from firing ...... in my mind. Then it would be a common problem and common knowledge. Lancer to me is the end all be all magazine so it's hard to pin this one down

The non-Lancer mags tossed the shells all in an area about 3 feet in diameter, at between 4 and 5 o'clock. Normal, IMO.

The Lancer mag tossed the empty cartridges at 1 and 2 o'clock about 5 feet away, in a circle about 2 feet diameter. After the 4th or 5th shot, when I looked down towards my feet, that's when I noticed the brass on the ground. After that, I had one of my fellow enthusiasts out that day spot and he mentioned all the rounds landed forward, in the same general pattern. Wished I snapped a photo or two.

This is definitely a question mark.

As I mentioned, I'm not bashing Lancer. I'm just curious as I'm looking to optimize rifle(s) with mag and ammo for peak performance (and hopefully 100% confidence, as overgassed or undergassed could cause FTF or FTE).

 

[RaceFan]

The added spring tension would add drag to the bcg.(ie-pushing the bcg upward in the upper. Binding of the bolt in the extension due to misalignment.) Could the mag sit too far in the mag well? Any wear marks on the feed lips?

Not that I can tell. The first two photos are of the same Lancer mag in question. The next one is the C Products. The last is the D&H from Palmetto. Heaven forbid you ask to see the PMag as I would have zero clue which one since I have maybe two, or more, LOL

I fired at least 25 rounds from each mag shown. Any drag or wear should show IMO. But I'm not seeing anything.

FWIW, the D&H has been used in several outings. The Lancer and C Product were first time use.

 

[oli700]

I get it , if I found a problem I'd bash a bit . No accusations here . Strange problem . I honestly have a crap ton of exp with the AR mechanics and spent about 6 years in the firearms industry making barrels . I have never ever heard of this so I am very curious to find out what it might be .

 

[osprey]

Tolerance stacking between Lancer mags and lower causing mag to sit a bit higher dragging on bcg?

 

[osprey]

Fire one round then eject live round that chambered looking for rash on it from too much interference with bolt carrier as it is coming back.