Magazine Top Off

[jimmyj]

An agency I worked for back in the days of transition from revolvers to autos the rule was not to have a full magazine with a round in the chamber. Reason given was it was too much stress on the extractor.
Was this valid ?

 

[Denverd0n]

Absolutely NOT!

 

[LVSteve]

Maybe some of that came out of Vietnam where I believe soldiers were encouraged to load their mags a couple short.

 

[robertrwalsh]

Not that I ever heard of. For years SIG recommended that you NOT top off their guns for police use for a very practical reason. IF you chambered a round and it worked just fine and then you remove the magazine to put in another round that then reinsert it you run the risk of a problem, such as the magazine not seating quite right. Then you have a one shooter rather than a 16 shooter. Not a completely BS reason.

 

[stansdds]

Rounds in the magazine have no impact on the extractor, so it was a rule made from myth. What damages pistol extractors is placing a round in the chamber, then letting the slide slam forward.

 

[Pisgah]

Sounds like supervision was confused with that policy. It's not being fully-loaded that risks damage; it is dropping a round into the chamber and then allowing the slide to drop, forcing the extractor over the cartridge rim without the "cushioning" action of stripping a cartridge from the mag.

 

[BAM-BAM]

IIRC the Brits [SAS?] had that practice with their Hi-Powers.

With todays mags; Glocks 17/19s and Mec-Gar now making 16 /18rd mags for the Beretta 92 Compact it might make sense ......... when I first started to carry it was just 6rd in a PPK,8 in a model 39 and 7 in 1911 mags..

These new mags are "tight" with a closed slide...... a good rap is needed to seat them.


Had a well respected Gunsmith here; make the same point recently on another Forum

 

[Chuck Edwards]

Some magazines are really hard to seat with the slide forward when loaded to capacity. My M&P45 and Beretta PX4 magazines are like this, and this is the reason the old advice that M16/AR15 magazines should be loaded to 28 rounds came about. Current production M16/AR15 mags are designed to be seated easily with 30 rounds, and I download my M&P45 and PX4 reload magazines by one round so they seat easily.

 

[Oldsalt66]

Short answer, that's nonsense.

 

[GnarlsR2]

These new mags are "tight" with a closed slide...... a good rap is needed to seat them.

Besides the uncomfortable extra amount of whack it takes to get a fully loaded higher capacity mag seated with a closed slide, I do NOT like the mental attention for the split second amount of distraction to make damn sure I have fully mounted the mag.

 

[THE PILGRIM]

Recently bought a SIG 365 X Macro, it came with 2- 17 round magazines.
Bought 2 more.
It took several loadings before I could get 17 rounds in all four.
Yes I was using a Loader.

 

[GnarlsR2]

Recently bought a SIG 365 X Macro, it came with 2- 17 round magazines.
Bought 2 more.
It took several loadings before I could get 17 rounds in all four.
Yes I was using a Loader.

I also bought 2 17-round mags, after about 45 minutes of frustratingly trying to get 17 rounds into the mags WITH an UPlula, I returned them to Sig.

 

[chief38]

I've never had any issues what so ever with fully loaded magazines in semi auto pistols assuming the pistol and magazine were working properly to begin with.

That story had something to do with M1 Carbine and M16 rifles when using 30 round magazines. I believe that issue has long since been addressed. In quality made pistols it is a non issue.

 

[GnarlsR2]

Unfortunately, based upon 100s of YouTube videos and 10s of thousands of posts on firearm forums, it appears that a "quality made pistol" is becoming quite rare.

So far, the only handgun I own that I will label as "quality made" is my 1977 Colt 45 MK IV Series 70.

I had one failure to feed in my BG2. I suspect it was caused by a fully loaded 10-round mag that I popped in with the slide closed. When I slingshotted the slide the round did not chamber.

For my defense firearm I want ZERO performance issues, so I will continue to load ALL my mags 1 round short of full.

 

[Krogen]

Seems like a lot of misinformation exists. Fixed extractors like in a 1911 can get damaged when the hook is forced over a cartridge rim. Drop the slide on a round in the chamber and the hook has to "give" to get over the rim. Normally, when fed from a magazine, the rim slips upward under the hook. This doesn't force the hook bend very much if at all. This potential stress on the extractor doesn't exist with a spring loaded extractor. The extractor will just snap over the rim.

Next, a completely filled magazine can be difficult to seat with a closed slide in some pistols. Sig's P365 is a great example. I find it takes a substantial squeeze with 4 fingers on top of the slide and my thumb on the magazine's floorplate. Simple enough in a stress free environment, but not something I want to do under duress. I submit that it can make sense to download extra magazines you carry, so they seat easily if you have to reload in a crisis. The risk is the magazine can fall free if not latched. It might seem latched, but fire a round and you may fail to strip off the next round or the mag can drop out of the pistol.

 

[GnarlsR2]

Seems like a lot of misinformation exists. ... I submit that it can make sense to download extra magazines you carry, so they seat easily if you have to reload in a crisis. The risk is the magazine can fall free if not latched. It might seem latched, but fire a round and you may fail to strip off the next round or the mag can drop out of the pistol.

With my BG2, even the 10-round mag with 9 rounds loaded requires a deliberate amount of extra force to mount it with the slide closed. With the slide locked back and inserting the mag produces a very distinct louder clicking sound. Even with my Walker's Earmuffs on, at the range, that louder click gives me more confidence that the mag is properly latched. At the range now, as a matter of practice, I will lock the slide back before I insert the mag, and slingshot the slide with my hand to chamber a round.

 

[WR Moore]

There's two possible issues with cramming a full magazine into a firearm with the bolt/slide in battery.

The first possible issue is that the spring pressure on the top round is enough to make feeding a problem. VERY slight possibility that the extra drag on slide slows the slide enough that it's not moving fast enough to make a clean strip of the next round. There is a rebound effect from the bolt/slide hitting the buffer/frame. I do think this is the BHP issue, aided originally by a hump in the feed ramp. Not sure if it's magazine design or production tolerances, but being one down on the mag in the gun (with round in the chamber) is insurance that the mag will feed.

The second issue is that after being heavily compressed, there's enough drag from all the rounds in the box that the top round doesn't move into proper position and/or will no longer strip cleanly.

Finally, it's rare, but I've seen it: the bolt actually deforms the body of the top round.

My personal standard with the MSR family is that if I press down on the top round, I want the base of my thumb nail to be level with the top of the feed lips.

One year during our annual run & gun stress course we had some newbies loading mags for us. When I went to chamber a round, the gun locked up. Seems at least one was loading the P Mags until they couldn't take any more rounds. There was a short show & tell about magazine loading.

 

[geeollie]

Jimmy, if you are about my age, the transition from revolvers to autos was around 1911. Before that we carried 5 rounds in our 6 shot, single action Colts. If we fell off our horse, there was not a round in the chamber to go off.

 

[glenwolde]

Jimmy, if you are about my age, the transition from revolvers to autos was around 1911. Before that we carried 5 rounds in our 6 shot, single action Colts. If we fell off our horse, there was not a round in the chamber to go off.

Did they make you trade in your sabers at that time?

 

[GnarlsR2]

The second issue is that after being heavily compressed, there's enough drag from all the rounds in the box that the top round doesn't move into proper position and/or will no longer strip cleanly.

After issues with the amount of force required by my UPlula to load my Sig P365 mags, I bought MagGuts +2 mag kits. That made a huge difference in my ability to load the 13 rounds in the 12 +2 kit.

I'm hoping MagGuts will make a +2 kit for the BG2 mags.