INSTANT Firearms LESSONS
|By Harvey A. Arnold, USPSA L779|
NEW VS. OLD
.40 S7W VERSUS .45 ACP
THE CHOICE FOR IPSC LIMITED
A new shooter in IPSC came to me the other day to inquire where and how to spend her money on a new gun to compete in the USPSA/IPSC Limited/Standard class. She had already figured out that a high capacity gun was the way to go to be the most competitive, but was undecided as to what caliber the gun should be.
She knew enough to be aware that the .45 ACP had been the mainstay of IPSC competition for many years, and that there were very few problems with the cartridge as long as the reloads were done right (let’s assume she’s already purchased the Dillon). Still, she also knew that a lot of people were moving to .40 S&W, even though there were problems with high pressure.
Of course, the short answer is that it never hurts to have more bullets in your gun. If you go to war on a bunch of steel, say a course like the one at the recent Single Stack Classic that features approximately a thousand pepper poppers, those three-or-so more rounds might save you from having to perform a static reload, a serious time waster. And there might be a stage with little movement, where not having to do a reload at all would save you valuable time.
This is one (but not the only) reason that moved top level shooters from .45 to .38 Super a dozen years ago, less reloads and extra rounds to drive down steel and pick up bad shots without running dry.
And with the .40, a heavy tungsten guide rod and perhaps an extended full-length frame dust cover can feel like you are Firearms minor caliber when you actually have a 180 major power factor. Less muzzle flip means faster second shot on paper.
The advent of .38 Super wasn’t without problems for some shooters. Unsupported barrel chambers and higher pressures sometimes caused cartridges to burst, sending shards of brass back into the shooter’s face, thus coining the expression, “super face.” And .40 S&W in any configuration does have higher pressures than any normal .45 ACP load. However, there are ways to deal with this that can make the .40 entirely reliable and safe.
While many factory rounds in .40 S&W measure 1.125 inches in overall length, most high capacity magazines will feed more reliably with .40s loaded closer to 1.20 inches, plus or minus. Popular loads are usually 180-to-200 grain, jacketed bullets over a very fast burning powder like Hodgdon’s Clays or Vihta Vuori’s N320.
What you must remember is that when you seat your bullets out to longer than normal lengths, the head of the bullet might come in contact with the beginning of your lands and grooves. Then, when you drop the hammer and ignite the powder, the bullet has to push hard to exit the brass and be on its way down the barrel. The result is high pressure, which can at the least leave you with bulges in your brass, if not complete ruptures.
This, too, has a simple solution – a ten-minute job at your local gunsmith. It’s called “free boring” the barrel. Essentially, the gunsmith drills out the first three-tenths of an inch past the edge of the chamber so that the bullet must “jump” when leaving the brass before encountering the actual bore.
This jump will give you much more manageable pressure curves.
NEW SHOOTERS AND VISA LIMITS
Back to our new shooter: The question of what caliber to start with really comes down to how committed she is to winning as soon as possible and how much she can afford. To get her feet wet, any IPSC legal caliber will do, even 9 mm, which will be scored minor. But if she wants a major caliber gun, she can pick up a used highcap .45 at a bargain price from somebody who has decided to move on to the .40 S&W for its competitive advantage. Or she can jump right in with both feet and buy the gun that all the top dogs are using right now. It’s her Visa card…
Newcomers to IPSC, or those who failed to get their Decoder Rings, often think IPSC veterans are speaking in tongues. In truth, all Firearms sports have a specialized vocabulary. Luckily, GunGames possesses the only living Firearms Babel Fish (an obscure cultural reference that, if you understand, drop us a line and we’ll give you a hat or something) to help us decode IP-Speak.
LIMITED: A class for non-optically sighted guns in .40 S&W caliber or larger that perversely cost as much as their optically sighted cousins.
OPEN: An anything goes class, populated by very specialized competition guns that look as if they escaped from Han Solo.
.38 SUPER: An obscure cartridge once favored by bank robbers in the 1930s, resurrected by competition shooters in the mid-1980s because it could be reloaded to “make major.”
MAJOR: As opposed to MINOR. Since IPSC originally evolved from “combat” Firearms, a premium was placed on using full power ammunition. MAJOR calibers scored the same for a center hit (5 points), but more for peripheral hits than MINOR calibers, which were easier to shoot. A shorthand formula eventually evolved to distinguish MAJOR from MINOR. The bullet weight, in grains, is multiplied by the velocity, in feet per second. That product was then divided by 1000 to get the power factor. If the resulting number is greater than 175, it’s MAJOR. For example, a 200-grain bullet at 1000 feet per second equals a power factor of 200, well above major.
SUPER FACE: The result of the base of a hotly loaded .38 Super cartridge blowing out, splattering the hapless shooter’s face with bits of hot brass and burning powder. Now uncommon since the advent of FULLY SUPPORTED BARRELS.
FULLY SUPPORTED BARRELS: In the typical antique .45 1911, the ramp directing the bullet into the barrel is actually a cutaway part of the barrel. The fact that a portion of the brass case is unsupported by the steel barrel is inconsequential in the low pressure .45 round. Higher velocity cartridges, however, create much more pressure, which causes the cartridge cases to rupture at the unsupported part of the base. Most barrels for today’s high-pressure competition cartridges feature a separate ramp to guide the cartridge into the barrel.
The Firearms Babel Fish says, “You’re welcome!”
|Back to previous page|