I've always been told that dry firing a pistol was bad for it. My Dad used to always say this, but he was always a rifle guy and never actually owned a pistol.
I got my first pistol experience in the Marines and one instructor said the same thing, although when I became a pistol instructor, none of the instructor trainers said anything about it.
Any clarification?
Those are very general statements. For example, which pistol was the Marine instructor speaking about? What sort of action did it have? Hammer or striker fired? You see, there are many possibilities so a blanket statement about dry firing doesn't fit all molds.
In terms of a Glock, dry firing is fine. If you are really concerned about this, get some snap caps and use them. As for modifications, I wrote something about this for Glocks recently on another gun website. You might find it helpful.
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The best advice to come out of this video is to do what works best for you, not what others may use or try to convince you to use. I would add to this my own advice which is...
Ignore people on websites that tell you to leave the gun alone; that it is fine as is and was not meant to be modified. Conversely, I would also suggest that you ignore those who go into some length trying to convince you to do so much as to nearly remake the gun. And when I say ignore, what I mean is while it is fine to read what they have to say, keep in mind that what you may decide to do is totally up to you and no one else.
Everyone has their own requirements, ideas, opinions, experience, and criteria when it comes to embracing a firearm and using it for whatever reason; target, self defense, or both. So listen if you will to those who offer good and honest information which falls within the framework of teaching you what you may not know or may wish to consider. This is all well and good. But do keep in mind that when all is said and done, it is YOU who has to live with your gun and any modifications made to it.
Now with that all said, some modifications are pretty much a given with some guns and Glock is no exception to this. Two of these were pointed out in this video: the grip plug and after market sights. Any Glock will benefit from both of these changes. I would suggest that while the plug can be installed without any hesitation right away, new sights should wait until the owner of the gun has enough range time so that he can take a qualified and proper decision as to which sights will serve him best and why. What his sight requirements are and that is only going to come out after shooting the gun a bit under varying distances and conditions.
You may not know what you're looking for in after market sights even after some range time until you can specifically point out the reasons you want to upgrade. I found this to be true. And you can go through several sets of sights before you find ones that are best for your needs. I also know this to be true from my own experience.
Grip texturing, trigger mods, recoil springs, striker springs, safety blocks, barrels and more are all things best left to wait until you are familiar with your gun and can give real reasons for making changes. And how the gun is going to be used will affect your decisions. Target, self defense, or both will carry weight to any modifications you make.
Now at the beginning I mentioned to ignore some suggestions and comments from people on the web and that includes those from myself. I would hope you come away after reading this with one thought. That you give it a little time and a chance, you and your gun, before you jump into mods. If for no other reason, do this so that you will actually know how and why you are going to modify your gun.
There is nothing wrong with making modifications that help you be a better shooter. Just make sure those modifications you make serve your needs as best they can.
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Here's a link to the video mentioned in the above.
http://www.youtube.com/watch?v=f7ViI2UWFKg&feature=player_embedded
I can't comment enough that you should do what you believe to be best for your specific wants, needs, and requirements. I would only add to that to do so after research and involved consideration.