The Gun Blogs

While there are exotic arms which fire the .50 BMG the .500 Magnum is the current "over the counter" big kid on the block. The cartridge was developed by Cor-Bon with the "X-Gun engineering team at Smith & Wesson for use in their Model 500 revolvers and introduced in February 2003 at the SHOT trade show. Currently only a handful of models have been introduced that fire this massive caliber, including the X-Frame Model 500 revolver from Smith & Wesson, Magnum Research's "BFR" (Biggest, finest revolver), the Taurus Raging Bull and German Janz JTL-E 500. Each holds only five rounds to allow for thicker cylinder walls to accommodate the pressure generated by such a large and powerful cartridge.

It is claimed to be the most powerful handgun cartridge commercially manufactured with over 2500 ft·lbf (3.5 kJ) of energy created with a 440 gr (29 g) bullet travelling at 1625 ft/s (495 m/s). Some loadings can even achieve muzzle velocities of 2300 ft/s using a 325 grain (21 g) bullet. This produces a muzzle energy of over 3817 ft/lb. A good average is 350 Grains travelling at 1975 ft/s.

Bullet weights available for this cartridge, range from a 265 grain jacketed hollow point, to a 700 grain cast lead bullet. Moderate velocity, heavy bullet loads from the .500 S&W Magnum are similar in performance to the black powder .50-70 Government.

So, how does this stack up to say, being hit by a small car?

2,000 lb Car20 mph = 29.4 ft/s Light Car= 2,000 lbs. = .05 X (2,000 X (29.4X29.4)) = 86,436 ft/lbs
350 Grain .500 Magnum1343 mph = 1975 ft/s 350 Grains= .05 lbs. = .05 X (.05 X (1975X1975) = 9,756.5 ft/lbs

The base argument, and you would be right, is that the bullet translates its energy more efficiently as it has a smaller surface area. This being paper science does not take into account the surface area of contact which will reduce the amount of weight usable in transferable energy, but it does give us some idea of the equivalent potential energy. It also does not take into account the pull of gravity which effects the energy of objects in flight.

To level the field if we add in the pull of gravity we can better see the differences in terms of base energy which is closer to the advertised energy of the .500 magnum.

2,000 lb Car20 mph = 29.4 ft/s Light car= 2,000 lbs. = .05 x (2,000/32.4x(29.4X29.4) = 2,667.76 ft/lbs
350 Grain .500 Magnum1343 mph = 1975 ft/s 350 grains= .05 lbs. = .05 x (.05/32.4x(1975X1975) = 2,971.64 ft/lbs

The intended design for this cartridge is for big game hunting and wilderness protection, as well as for ultimate defense (bears, etc). As we see from our calculations the energy from the 350 grain .500 Magnum is very close to a car travelling at 20 miles per hour, though I wouldn't expect the same results. So I imagine the cartridge is pretty well suited for its intended purpose.

So please, shoot as you drive, safely and with one on on the road. You thoughts, as always, are much appreciated.

Link Textwww.gunshopping.blogspot.com

The HK P7 is one of the most unique commercially available pistols today. While it is no longer in production there are a number floating around at gun shows and though dealers. I will dive further into its function later, but lets just say that everything going into its unique design makes it one of the safest and accurate handguns on the market. Out of the box no gunsmith required.

HK P7 pistols can be drawn, cocked and fired accurately, faster than any other pistol. The unique HK design allows the P7 to be carried safely with a round in the chamber and the pistol completely uncocked. Cocking is accomplished quickly, without changing the firing grip and by depressing the cocking lever located on the front of the grip. There is no heavy first shot trigger pull like that found on a conventional double-action pistol. There is no change in trigger pull between critical first and second shots.

To ensure accuracy, P7 pistols use a fixed polygonal barrel made by cold-hammer forging. Polygonal rifling seals propellant gases behind the bullet and increase barrel life. With its fluted chamber, the P7 will extract and eject an empty shell even if the extractor is missing. The extractor, which doubles as a loaded chamber indicator, only aids in making extraction smooth and uniform.

Specifications
Heckler and Koch P7M13
Caliber:
9mm (9X19)
Length:
6.9"
Barrel Length:
4.13"
Weight:
1.87 lbs.
Capacity:
13 Rounds
Cost:
$1,400
German engineering. In a world of compromises...some don't. Your thoughts, as always, are appreciated.

Link Textwww.gunshopping.blogspot.com

On the outside the LDA model of 1911 pistol looks much like the other numerous variants of 1911 handguns. However in looking at the internals it is not a traditional 1911 in the slightest.
The hammer is comprised of two parts, an internal cam (70) and a traditional external hammer (72). The internal cam is attached to the hammer strut (62) which stores the energy of the mainspring (56). The sear (42) is connected to both the hammer which captures the face (108) within a notch (112) until it is pulled clear allowing the pistol to fire. The sear also holds the internal cocked cam until released. The sear is physically contained within the hammer while holding the internal cam from rotating. While this simulates the hammer being cocked from an internal point of view, externally the hammer is in the resting state.

To fire the pistol the trigger is pulled which rotates the hammer until it trips the internal cam. The internal cam then releases its energy into the external hammer which impacts the firing pin. The slides recoil pulls the hammer rearward cocking the internal cam and the external hammer returns to its resting position.
While the external safeties look the same as the traditional 1911 they function in a unique manner. The grip safety articulates a lever that locks into the rear of the external hammer. Once depressed the lever moves clear of the external hammer allowing the external hammer to move freely. The thumb safety locks into the external hammer and internal cam rendering the firing mechanism inoperable.

Thus, we have a pistol which provides the accuracy advantages of a single action pistol with the advantages of a double action pistol. While the trigger pull is reported to be long it is steady and light.

From a safety standpoint you get the best of both worlds without the negatives of either. The internal cam with the stored energy of the mainspring never comes into contact with the firing pin. The external hammer, which is exposed to the greatest chance of colliding with external forces is not only always in the down position, but contains none of the stored energy of the mainspring.

www.gunshopping.blogspot.com

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For those who want to really do it yourself here is a parts list with prices for building your own Glock. Yes it can be done. Better than the original, this has a match barrel, stainless steel frame and aluminum trigger.

Parts are from Brownells www.brownells.com
The parts list:
CCF Stainless Race Frame: $349.95
Caspian Slide: $179.00
Briley Barrel: $158.00
Aluminum Trigger: $86.59
Recoil Spring Assembly: $19.97
Firing Pin: $49.97
Firing Pin Spacer Sleeve: $1.97
Firing Pin Spring: $1.97
Firing Pin Spring Cups: $1.97
Firing Pin Safety Spring: $1.97
Extractor w/Loaded Chamber, New Style: $19.97
Extractor Dep. Plunger Spring: $1.97
Spring Loaded Bearing: $1.97
Spring Loaded Bearing LCI: $1.97
Slide Plate Cover: $3.97
Sight, Rear, Adjustable: $24.97
Sight, Front: $1.97
Magazine Catch Spring: $1.97
Magazine Catch: $1.97
Slide Lock Spring: $1.97
Slide Lock: $3.97
Locking Block: $24.97
Trigger Housing w/Ejector: $4.97
Connector, 5 lb: $3.97
Trigger Spring: $1.97
Slide Stop Lever w/Spring: $7.49
Trigger Pin: $1.97
Trigger/Housing Pin: $1.97
Locking Block Pin: $1.97
Firing Pin Channel Liner: $1.97
Trigger Spring: $1.97
Extended Slide Release: $14.97

Total: $984.25

Cost of New Glock: $605.99

Diff: $378.26

If you upgrade the Trigger and Barrel it adds $244.59 bringing the total to $850.58