Okay, were in the depths of summer, and for some of you it will stay hot for quite awhile. Others can look forward to a break in the heat in a while, but in the meantime were all sticky with sweat and tired of packing a big ol blaster. We all want something smaller and easier to hide under hot-weather clothes.
But there is a catch (isnt there always?) Compact guns come with their own demands. Like the cutest sister at a sorority house, an ultra-compact carry gun can be demanding and insistent. Some things just might not be good enough. And others, well, lets just draw the curtain on this particular comparison.
Ultra-compact handguns, besides having specific needs in holsters, can be very particular about the ammunition they will work with. You may find that some combinations are simply unreliable, and not because the gun, the ammo, or your wallet are at fault. No, some things, like kimchee and key lime pie, just are not meant to go together.
Lets start with you revolvoleros. Youve suddenly discovered the benefits of packing an ultra-light snubbie. And not to pick on them, but lets assume you went with an S&W 340PD. (Nice gun, by the way.) If you look at it closely, or even read the owners manual, youll see a warning laser-etched on the barrel shroud. It tells you not to use ammunition of less than 120 grains weight.
Why? A little thing called bullet pull. You see, when you touch off a sub-critical nuke in the 340PD, recoil happens. The revolver moves back, as Sir Isaac noted, when the fired bullet moves forward. As the cylinder moves back, it snatches the remaining cartridges to the rear, and it snatches them by their rims. The bullets in the remaining rounds do their best to keep up, but if the recoil becomes brisk enough, they fail in that task.
The faster and more forceful the recoil, the greater pulling force on the bullets. If the bullet pull becomes great enough, the remaining rounds lengthen. Why the warning on lighter bullets and not on heavier ones? Wouldnt the lesser recoil of the light bullets make the heavier bullet more likely to pull? Nope, you see, the weight of the heavier bullets comes with a longer bullet length. Longer length in the bullets means more friction in the case, and thus a greater resistance to pull. Dont go putting all this on S&W, by the way. Any sufficiently lightweight revolver, using sufficiently powerful ammo, is going to experience this problem.
You snickering pistoleros, stop it. You have the opposite problem. When your featherweight pistol recoils, the rounds are rattled back and forth inside the magazine like the goodies in a miniature pinata. The timing of the short slide and the magazine spring lifting the rounds has to coincide, or you get failures to feed. What was a perfectly reliable compact 9mm with standard ammo may be a jam-a-matic with +P or +P+ ammo.
The hotter your carry ammo is, the more forcefully and more frequently those rounds bounce back and forth. If there is insufficient neck tension on your ammo, your rounds will shrink. If they dont shrink in the magazine, the bullets may still have been loosened enough that when they get to the top and try to feed, they end up shortening when they are slammed into the feed ramp.