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View Full Version : Dry Firing, a different perspective



coolbox18
04-12-2011, 02:15 PM
I will start with saying that one should use snap caps, and that I am discussing the cz75b type weapons, that have a firing pin block. (please note that most weapons have copied this design, so just compare pictures with cz75b or it compact or decocker versions, including p07 duty).

Their design incorporates a cross pin to retain the firing pin in its position. This cross pin gets badly damaged by dry firing, as it is hollow in design. I was lucky I had (and have) in spare, so changed just in time. The cross pin runs across the slide, left to right, in the rear serration area (from where we hold and rack the slide), visible as a small hole in below picture.

An easy method to avoid damage while dry firing is to make a thick ball of tissue paper, place it at the base of hammer, between hammer and slide area. The cushioning should be think enough to avoid the hammer striking or contacting the firing pin. This can be ensured by using a pencil. Place the pencil in the barrel, flat side facing the firing pin. If the hammer 'strike' makes the pencil move or fly out, the cushioning is not enough, and a thicker ball of tissue paper will be required. I have made this SOP for all my dry-firing sessions involving handguns, be it with firing pin block or without. For those wondering what is different in weapons without firing pin block, the are retained by a block at the end of the slide, instead of a cross pin, so there is no cross pin to get damaged, and snap caps alone should be enough.

The parts that do get stressed are:
1. The firing pin, as it is constantly struck by the hammer during dry firing session
2. Firing pin spring, which absorbs the forward motion of firing pin, and brings the firing pin back in position
3. Hammer surface contacting the firing pin, usually a small dent is created, which is normal so far as no light strikes on live primers are observed
4. Hammer or main spring
5. Trigger return spring. Do not expect this to last over 10,000 rounds of dry firing in CZ75 models, that is the rated life, beyond that is bonus..


For glocks and wanna-be glocks, I have no idea what damage can be caused, but use a snap cap to minimize the damage.

Aquarius
04-12-2011, 06:27 PM
Great input coolbox bro.. thanks for sharing this usefull information.

HussainAli
04-12-2011, 07:30 PM
Dear CoolBox Bro,

Nice share !!!

Regards

Aquarius
04-12-2011, 11:49 PM
Dear coolbox bro.. sorry for not asking this question in my previous post.
Is this dry firing story applicable for CZ models with firing pin block models like CZ 75B, D compact, P07 Duty, Rami, 97B etc etc.. or is it applied with models having no firing pin safety eg CZ 85 Combat, Shadow, TS, Czechmate etc.
I know the trigger return & the firing pin return springs will wear & tear in the same way as mentioned above with or without dry firing, but if the firing pin block breaks (Khuda Na Khwasta) in the models having it, then it will become a CZ without a firing pin block.. 4 example after breaking of firing pin in CZ 75B, it will become a pre B model or a CZ 85 Combat without Ambidextrious controls.
Please correct me if I am wrong.

coolbox18
05-12-2011, 12:25 AM
@Hussain Ali bro, thank you.

@Aquarius bro, Thank you.
The above stands true for all weapons 'having' a firing pin block, and the problem is not with the block, but with the pin that retains the firing pin, which is located in the rear serrations of the slide (from where we grip and rack the slide), visible as a small 'dot' or 'hole' in the pic above. Guns with no block (85combat, TS, Shadow etc) do not have this pin, and hence only trigger spring and firing pin spring are the major wear parts.

Wolf Hunter
05-12-2011, 01:35 PM
The above mentioned trial may be good and of course good to reduce the effects of dry firing but what I personally feel that interference or creating barriers in natural move of moving parts of handguns ( or any other machine ) will create trouble sooner or later.
In this case I find that we are not doing justice with sear assembly or sear itself. Since the manufacturing of guns sear is a part which has seen very less changes and modifications.The edges of step over sear, when worn out, loses its strength of holding back the trigger and it is very dangerous scenario and it can fire a bullet without consent.Now in your this case ( putting tissue) is likely to wear sear prematurely and risking the life of firer.

coolbox18
12-12-2011, 09:06 AM
@wolf hunter bro,
You are correct. The above is on top of what you believe are the wear parts (sear-hammer assembly and connections). However, sear may last over 25-30k dry fires, even more, as this assembly is supposed to last the lifetime of the weapon, but not this firing pin retaining cross pin. It will give up much sooner. This is the reason I had to mention this.

Regarding putting tissue, the only thing it does remove is some (extra) oil from the hammer area. It has almost no contact with sear, actually has nothing to do with the sear. It is placed between hammer and firing pin region (outside the slide, rear side), and is done by quite a few competitive shooters at range, although it does not make up for live firing.