Dry Firing a Center Fire? Making Snap Caps...

[gxsr-sarge]

I just posted a thread regarding looking for snap caps/dummy rounds for a 404 Jeffery (http://www.africahunting.com/firearms-ammunition-general/13910-snap-caps-404-jeffery.html) but realized that I should have posted a broader discussion here.

My objective is to make dummy rounds for cycling/rechambering/reloading practice drills on a 404 Jeffery - not necessarily "snap caps" for merely dry firing. A-Zoom snap caps (full dummy rounds) are no longer made in 404. All that I've found are "snap caps" (i.e., just the case).

1. The first discussion is whether dry firing a center fire is acceptable. My understanding is that it is OK to dry fire any "modern" bolt action weapon. I just purchased a CZ 550 Safari Classics in 404J. If it is truly OK, then I could just load primer-less rounds clearly painted/marked and drilled out (on the side of the shell).

2. If not, then the question becomes what material (gasket material, silicone, leather, rubber, etc.) could I install in the primer pocket in order absorb the impact of the primer?

Any input would be greatly appreciated!

Thanks in advance!

 

[Johnny7604]

For the most part dry firing modern centerfires is fine on a limited basis. However if you are planning on doing it alot I think you are right in fabricating snap caps. The last thing you want is a fractured firing pin in the field.

Of those materials listed I think a firing pin would punch a hole in them in short order. I would see if I could find something a little more high density. Some sort of heavy duty plastic perhaps.

John

 

[toxic111]

I have heard that a pencil eraser makes a great 'primer' for 'snap' caps

 

[gxsr-sarge]

I was thinking this type of plastic:

Shepherd 3/4 in. Plastic Base Nail-On Cushion Glides 4 Pack-9446 at The Home Depot

I'm not sure if it's "Delrin"

 

[gxsr-sarge]

Of those materials listed I think a firing pin would punch a hole in them in short order. I would see if I could find something a little more high density. Some sort of heavy duty plastic perhaps.

John

I'm wondering whether the objective is for the pin to strike something "hard" or something with a little more "give". Some if the cheaper snap caps are made with internal springs to provide some type of "give" to the "primer". Would more damage be caused by he pin striking a firm surface?

 

[Royal27]

From what has been explained to me dry fire is fine in modern bolt rifles, but not shotguns, doubles, or rim fire. It has to do with the shoulder of the bolt stopping the pin and not the primer. Sarge, I received this info from the SAAM guys so you may want to ask Tim this question when you talk to him.

That being said, doing something extra to protect the firing pin sure won't hurt!!! And "real" ammo is certainly better for training and drilL's, IMO.

 

[Uintaelkhunter]

I would contact harbour arms they make custom snap caps.

Delrin is your best bet for use but it does indent over time without a spring behind it to absorb the impact of the firing pin. If you have access to a lathe you can drill out the primer pocket of a factory round make a Long delrin shaft with a spring guide and spring at the end as to contact a bullet or delrin blank you will set as a bullet at the other end

 

[Johnny7604]

I'm wondering whether the objective is for the pin to strike something "hard" or something with a little more "give". Some if the cheaper snap caps are made with internal springs to provide some type of "give" to the "primer". Would more damage be caused by he pin striking a firm surface?

The issue is more the shoulder of the firing pin striking the bolt with full force. As long as the material of the snap cap is softer than the firing pin it should be just fine.

I have used old primers in the past. Eventually the pin will punch a hole through the old primer but when that happens you can just pop it out and install another discharged primer.

Not ideal I know but it works and is safe. Just make sure it's a discharged primer.

 

[James.Grage]

To make a inexpensive snap cap.

Have a brass casing and remove the primer.

Fill the primer hole with silicone and let harden.

use a razor blade to remove excess, if you really over filled the hole.

The silicone will provide a cushion for your firing pin.

Easy and effective

 

[gxsr-sarge]

To make a inexpensive snap cap.

Have a brass casing and remove the primer.

Fill the primer hole with silicone and let harden.

use a razor blade to remove excess, if you really over filled the hole.

The silicone will provide a cushion for your firing pin.

Easy and effective

Would you be able to suggest a specific type/brand of silicone?

 

[James.Grage]

DAP

It comes in White and Clear.

 

[Normana]

I have heard that a pencil eraser makes a great 'primer' for 'snap' caps

Yes, eraser works very well.

 

[C.W. Richter]

The only action that's ever messed up on us dry-firing is a c. 1900 Ithaca damascus steel sxs shotgun. That's it. We don't play John Wayne in front of the TV regularly with anything. The fix on the old Ithaca was $150 from Diamond Gunsmithing (used to work at Ithaca) in Ithaca, NY. We did it 1x more...LOL I personally see snap caps as yet another unnecessary for-profit widget sold in the shooting/hunting Industry. I also laugh at the laser boresighters! (just look down the barrel, position it at the target and adjust your sight-It works-without the $ale!) In one case on my son's Rem pump 3006, no scope adustments were necessary after precisely doing so on bags! (TY Ridgewalker! Did I show you the test target?) Real estate and Bonds pay dividends. American widgets suck people's pockets dry. Sure, it's cool for the seller's personal finances to sell 1M units of something that sells for $9.99. But, do you need it? No. Do that 100x annually and you'll have $10K plus compound interest per decade. Easily $100Ks in your retirement savings not spending money on BS. Perhaps the old doubles of any kind are sensitive to dry firing (as is my Son's 125 y/o Ithaca double.) 'Never a problem with my 50 yr old .22 WMRimfire. While ranting about personal finances, when your wife wants to waste $, just say NO! Best thing you could ever do. I could elaborate...LOL (This logic Favors the PHs.)

 

[C.W. Richter]

*late breaking-this just in...In your bespoke antiquities, simply insert checks issued by Silicon Valley Bank in the chamber and it can be very safely dry-fired.

 

[Inline6]

I have a rifle that has in excess of 300k dry fires and 30k rounds on the action.

If you wanted to make dummy rounds you can use hot glue in the primer pockets.

 

[FrontLines]

Nearly any modern centerfire that is good quality can be dry-fired without fear of damage.

However, rimfires (unless equipped with a firing pin stop) will typically peen the chamber edge if they are dry-fired.

There are exceptions, it's wise to consult your manual or the manufacturer.

Ok, my personal opinion on dry-firing in general.

Assuming that your manufacturer/manual gives you the green light to dry-fire, then you should be aware that there's dry-firing and then again there's dry-firing.

If you want to dry-fire 10 or 20 times before hunting season or maybe practice for a few minutes the night before the range trip then don't worry about it. Go ahead and dry-fire away.

If you intend to snap the gun a hundred times a night, every night, as part of a dedicated practice program then it would probably be wise to invest in some snap caps. They cushion the drop of the firing pin in the same manner that the primer of a fired round does and eliminate the stresses associated with dry-firing.

 

[Puddle]

I weigh a few rounds to get an average weight.
I fire a magazine's worth of rounds.
I leave the spent primers in the brass.
I fill the brass with fine play sand to the average weight of a round minus bullet weight.
I seat bullets.
I visibly mark the completed dummy rounds.
I go forth and dry fire practice with a magazine's worth of dummy rounds.

 

[Longwalker]

I don't believe any of the plastic fillers installed in place of a primer do anything but give a false sense of security for those who use them. I also don't think snap caps are necessary for bolt action rifles.

For my doubles and single shots, I use proper snap caps manufactured with hard plastic or brass plungers mounted in a special cartridge with a cylinder that is spring loaded. Like the ones sold in the USA by New England Custom Gun. That design provides consistent resistance to firing pin impact even after many, many "shots".

In comparison, softer plastic or rubber ( hot glue, rubber, pencil eraser etc) snap caps all deform after several hits, and subsequently do nothing at all to cushion the blow of the firing pin.

Dummy rounds are useful to prove the action is feeding correctly and for load / load drills. But proper snap caps are seldom made with the same weight and dimensions of a loaded round. I see Snap caps and Dummy ( action proving) rounds as two different functions.