what is "the right" capacity for a given pistol and how do manufacturers choose it?

[zukiphile]

Even with say .22LR, I read things like "well .22LR only functions reliably in magazines of 10 or less" and you got a whole bunch of manufacturers offering 10 round mags and that's it for such pistols, yet we seem to be able to put 25, 30, 40, whatever in a rifle mag and they run great, a pistol here and there or mag hacks exist in .22LR carrying 15, 17, 20+ rounds and they run great. Most of our .22LR pistols could easily fit a 15+ round mag, but it's only the fringe brands who offer that sort of thing out of the box. Why is that? How do they choose this stuff?

If you were around in the 90s, you may remember a 22lr pistol by Magnum Research that took 15 and 20 round magazines. It was sort of Ruger MKII-ish, and judging by the numbers of them I've ever seen, very few were sold.

After decades of shooting pistols at paper, I have a five round cadence tattooed onto my brain. I can deal with 10 rounds in a magazine because I can follow the same cadence. I once had a 12 round Ram-line magazine, but always loaded it to 10.

People should be able to buy magazines in whatever capacity they prefer, but the 22lr pistol market may reflect a convention amongst customers as much as any real engineering reason.

 

[veprdude]

I think it's definitely a cost and reliability thing foremost. You don't see Glock redesigning their pistols and mags for higher capacity. In fact, most models never receive an updated magazine style for the same model.

The only ones I can think of is Springfield with the XD to XDM line and Sig with 226 to 228/229 line. Gun is basically the same but mags are different. They made the 9 and 40 slightly wider which allowed a few more rounds for the same mag height. Wider magwell, wider mag, more capacity for the same length of magazine.

You can only do this so much until the grip gets out of proportion to the average (probably man's) hand.

Now when brand new models come out, you better bet the manufacturers are trying to maximize round count with width of grip to fit dead nuts in the middle of the bell curve of the average man's hand. Round count sells, but there is a diminishing return especially when it means the grip is getting wider at the expense of fitting fewer hands. Or the magazine is becoming ungainly long. If they're not doing this they should be.

15-20 in 9mm is the sweet spot until you can make materials thinner to squeeze an an extra round or 2 in.

 

[Brit]

Magazine capacity? It depends, back in 1980 I read everything I could on fights, good guys against bad guys. Trying to find a common denominator.
Did not take me long, to find out that mostly did not exist.
So there was an average magazine size, that made a given pistol to be able to be holstered and hidden on a belt, also to be deployed in a timely manner.

For quite a few years, a Glock 19 was just right. A 15 round magazine, plus one in the breech, 16 rounds of 9mm hollow points. Plus a Glock 17 magazine as a backup, mostly because a 15 round magazine, inserted in a rush, pinched my hand. All the experts stated that magazines being faulty, was the most common reason to change mags, not running out of rounds.
When I shot the gun games with my Glock 19, I never had any magazine malfunctions! Just changed magazines on lock back. Hence the extended mag' release/lock. To increase the speed of a magazine change.

Then out comes the newest Glock model, the 43X! Ten round magazine, the smallest slimmest and lightest Glock to date! The one I bought, Blue box, with factory-installed Ameriglo night sights. Ten and one seemed capacity enough?
Till the aftermarket, all-steel magazines entered the market place, so back to 15 plus one!

Does everyone remember the old joke? You only can have too many rounds in your magazine, if you are drowning, or on fire!

I coined a phrase MORE IS BETTER ALWAYS as a board member of IALEFI.
Still believe that.

 

[J.G. Terry]

USP Compact-non historical speculation

USP Compact-non historical speculation: I recall during the time of the original high capacity ban of shopping for a 40 caliber HK USP compact twelve shot magazine. The only magazine that showed up had an asking price of $100.00. Later, one retailer was giving away ten shot magazines with the purchase of high capacity post ban magazine.

USP Compact in 45ACP: One factor that dictates the size of the gun is the size of the 45 ACP round. The gun comes across as being designed as a military or police side arm. Consequently, intended use and need for long term serviceability in a medium size hand gun dictated shape, size plus magazine capacity. All these needs were met with a combination of features that came up with this eight shot relatively large handgun. Ambidextrous safety and mag release, plus option of a mode of firing made for easy changes. The gun appears to be made for a market where guns are cleaned once a year whether needed or not. I feel the American market had little to with design or magazine capacity of this gun. One local police force did issue the HK Compact. One complaint was the abrasive character of the grip. That force now uses Glock's.

 

[USNRet93]

You don't see Glock redesigning their pistols and mags for higher capacity.

That's EXACTLY what Glock did when they designed the 17->19 and 26,
the 22->23 and 27 and 20->29.

 

[Brit]

I carried a LW Commander, with McCormick 8 shot magazine, also a spare one, we used a full-sized 1911 in IPSC competition, suitably worked on by the homegrown gunsmiths spawned by this sport (Ontario Canada) we were buying new, in the box Colts, that would not feed hardball ammo! The carrying is US Carry Permits, no such ability in Canada.
When I sent my application to Florida, the permit was mailed to my Canadian address! Way back when. Not any more, but now as a US Citizen, no problem.
By the way, US Mil-Spec 7 round Colt Magazines? Rubbish. We all used the 8 rounders from McCormicks, stainless steel.

Prime Minister Trudeau of Canada, is talking about collecting all the Pistols, and AR 15 Rifles (Buy Backs?) Just like the Nazis did! Ring any bells. How many GIs and Canadian Soldiers died in that war? WW11. I LOVE Florida.