I had noticed that in 600-700 rounds, my primers were becoming more lightly dimpled than they were when my SW40VE was new. The gun has never malf'ed or failed to fire.
I'd never disassembled the slide on this gun. Being a Glock Armorer, it certainly isn't something I'd hesitate to do; but in practice I only pull slides down maybe yearly, or when something 'wrong' starts happening. Evidence of light strikes definitely fits the latter category.
Something which gets little mention in these threads is the matter of Firing Pin Protrusion (FPP). This refers to how far the firing pin protrudes from the breechface at the moment of firing. Industry Standard is between 0.050 and 0.055 inches. So long as you have that much FPP, an OEM strength striker spring and the cartridge is properly supported by the chamber, any primer will light off like it should. These elements work together as insurance against the worst-case scenario.
Measuring firing pin protrusion is within the abilities of any hobbyist who can read a set of micrometers. Brownells markets a little adjustable gauge specifically for this purpose; but with some autos and snubnose revolvers, you can use the 'stinger' of your vernier calipers. You simply take a reading from the front of the slide to the clean breechface, take another reading with the firing pin fully extended, and subtract the difference. The difference between the two figures is your firing pin protrusion.
When I checked the SW40VE, the readings were low- about 0.042". As closely as S&W copied the Glock design on these guns, I knew something was wrong.
When I pulled the striker, I shined a flashlight down the striker channel from the back of the slide. At its bottom is a shoulder which limits the final travel of the striker. There I observed several flecks of brass which had been battered bright against the shoulder in the channel. I also saw what looked like aged steel dust or chips down there. I grabbed a can of carb cleaner and hosed it out, following with canned air. After it dried I ran a long Q-Tip, soaked in Hoppe's No. 9 down it again, twisted it and backed it out carefully . Satisfied that it was clean, I took a fine stone and carefully removed a manufacturing (casting?) burr from the limiting shoulder of the firing pin itself.
Satisfied with my work, I reassembled the slide and checked the firing pin protrusion again. Dead-nuts 0.055 inches.
Now I'm sure at least some of you are familiar with the 'bic pen test'. This is where you use one of those straight ink pens, which has a separate cap, to check striker force. You simply remove the cap, drop the flat end down the barrel of an empty gun and pull the trigger. A good striker force will bounce the pen off the ceiling of most homes. You can also elevate the barrel 45 degrees and see how far the striker launches it, which is how I tested this particular pistol both before and after the slide tear-down. After the cleanup and burr removal, this SW40VE would launch it nearly twice as far as it did before the work. That tells me that things are much improved and I'm betting fired casings will tell a similar story.
I'd never disassembled the slide on this gun. Being a Glock Armorer, it certainly isn't something I'd hesitate to do; but in practice I only pull slides down maybe yearly, or when something 'wrong' starts happening. Evidence of light strikes definitely fits the latter category.
Something which gets little mention in these threads is the matter of Firing Pin Protrusion (FPP). This refers to how far the firing pin protrudes from the breechface at the moment of firing. Industry Standard is between 0.050 and 0.055 inches. So long as you have that much FPP, an OEM strength striker spring and the cartridge is properly supported by the chamber, any primer will light off like it should. These elements work together as insurance against the worst-case scenario.
Measuring firing pin protrusion is within the abilities of any hobbyist who can read a set of micrometers. Brownells markets a little adjustable gauge specifically for this purpose; but with some autos and snubnose revolvers, you can use the 'stinger' of your vernier calipers. You simply take a reading from the front of the slide to the clean breechface, take another reading with the firing pin fully extended, and subtract the difference. The difference between the two figures is your firing pin protrusion.
When I checked the SW40VE, the readings were low- about 0.042". As closely as S&W copied the Glock design on these guns, I knew something was wrong.
When I pulled the striker, I shined a flashlight down the striker channel from the back of the slide. At its bottom is a shoulder which limits the final travel of the striker. There I observed several flecks of brass which had been battered bright against the shoulder in the channel. I also saw what looked like aged steel dust or chips down there. I grabbed a can of carb cleaner and hosed it out, following with canned air. After it dried I ran a long Q-Tip, soaked in Hoppe's No. 9 down it again, twisted it and backed it out carefully . Satisfied that it was clean, I took a fine stone and carefully removed a manufacturing (casting?) burr from the limiting shoulder of the firing pin itself.
Satisfied with my work, I reassembled the slide and checked the firing pin protrusion again. Dead-nuts 0.055 inches.
Now I'm sure at least some of you are familiar with the 'bic pen test'. This is where you use one of those straight ink pens, which has a separate cap, to check striker force. You simply remove the cap, drop the flat end down the barrel of an empty gun and pull the trigger. A good striker force will bounce the pen off the ceiling of most homes. You can also elevate the barrel 45 degrees and see how far the striker launches it, which is how I tested this particular pistol both before and after the slide tear-down. After the cleanup and burr removal, this SW40VE would launch it nearly twice as far as it did before the work. That tells me that things are much improved and I'm betting fired casings will tell a similar story.
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