New Firing pin spring choice.

[Dave Hoback]

I've been looking, and finally came across a great substitute. It's a Flat wire Chrome-Silicon spring. These are ISMI sold as recoil springs for the Glock 19. I grabbed a 22lb, which is 31 coils. I then cut it to 21 coils for correct preload. These are a PERFECT fit for Model 10/110 adjustable firing pin. Much less play than the stock spring, and compresses straight down. (Doesn't bow out like the stock spring.) I'm going to see how this one does & maybe try some other spring rates.

https://i.ibb.co/VJ1mMqs/7-E6-D5151-3042-4911-AC28-89-C50-CDECA20.jpg (https://ibb.co/TYfLPgs)

[olddav]

Deleted

[mattri]

Same.

[sharpshooter]

Rated at 22 lbs at what compression height?

[Dave Hoback]

Rated at 22 lbs at what compression height?


I don’t concern myself. What many think of in terms of a spring’s “weight” as relating to firearms, is actually LOAD. The LOAD is the amount of force, typically shown as pounds, it takes to compress the spring 1”. When we play the game of clipping coils of stock springs, the LOAD is not changing, rather the spring rate is. Take two springs of the same diam. wire & coils spaced the same . One spring is 10 coils the other is 15 coils. In a given length system with equal preload, the 10 coil spring will feel lighter. However, if we were to further preload the 10 coil spring with spacers, it will feel as heavy as the 15 coil spring. I can type out all the math as to why this is but quite frankly, it’s just BORING to me....and there are FAR too many web pages dedicated to explaining it all! (Interwebs: it ain’t JUST for the Face Page & PORN!) I understand spring load/rate at least as well as the average bear...maybe a bit better. I know what works & how to choose. This is how I’ve picked specific springs for my Accutrigger setups. Striker springs are a balancing act though. Spring load/rate must be chosen as to not impart unneeded weight on the trigger release, yet it must have enough energy to ignite the primer.

[Robinhood]

Dave, I am very interested in your findings. I too have found alternative springs. Sending you a message.

[Dave Hoback]

Don’t know when I’ll actually be able to test it at the range, but I should be able to to just prime some cases and test those here at home.

[sharpshooter]

So basically you have no clue.....

[Dave Hoback]

So basically you have no clue.....

Whatever you say Fred.

[mnbogboy2]

Machinerys handbook has the formulae to calculate spring rate based on wite diameter, id, od and number of coils.note: adjust the flatware sectional area to match spring are cross sections.

[Dave Hoback]

Yes, thank you bogboy... Like I said, I could have typed out all the math, but again, it’s boring! And as has been said: I’ll leave the “Calculus” to better minds than mine. OOPS! I mean Algebra. Actually the formula for flat wire springs is pretty involved. I’m not worried about numbers based on formula. I’m using the things I already know.

Once again, the norm in firearms is to list springs by their load rating, while in reality we are worried about the rate & most importantly...the impact pressure. It’s argued that the impact force required to set off primers is like 65-75 inch/oz. We KNOW a stock Savage spring is rated at like 26lbs. And a stock spring provides MUCH more impact energy than 75oz! I’ve also increased pin fall. Not to mention the flat wire, Chrome-Silicon springs provide a greater release of stored energy. I still need to check a few primed cases. But honestly, it’s just going to illustrate what I’m already fairly sure of. (Based on comparing to my old set up)

[Dave Hoback]

Like I expected, wasting the primers was futile. CCI primers... no problem going “POP”. I’m going to pick up a 20lb spring to try next. Find out the absolute limit & use the next one up.

Boy... for having “No Clue”, I sure do get “lucky” with choosing things. Like...with EVERYTHING! I’m sure some have seen the video I posted of how light my bolt lift is. It’s actually lighter. And the Action is super smooth. To be fair, it’s not the spring alone. I’ve been tweaking the Action. Lapping the PTG bolt, which a few hare Kiff(did I say that out loud?) But I love them. I have nearly 100% lug lockup contact. The Rear Baffle, I replaced the bearing balls with 1/8” Tungsten Carbide bearing balls. I need to make up some dummy rounds & maybe make another video showing how quickly this thing can be be cycled. Maybe We’ll make it a “try to beat it” test. Seeings how I’m just so damn lucky!

Heres one fired primer. The primer is still perfectly round because it had no powder/bullet.
https://i.ibb.co/CnKhvY3/CE6-BB9-FF-FDB4-447-F-B5-F3-29-D1-B306-D614.jpg (https://ibb.co/MRkMptx)

[sharpshooter]

Just because it went pop, doesn't mean that you are getting all the energy out of the primer. There is such a thing as "cold fire". A primer can be struck hard enough to go off, but with not enough impact to expel all the energy. Low energy detonation accounts for fliers.

[Dave Hoback]

How did I KNOW that statement was coming? It’s like I’m psychic or something.

The belief of a primer strike which still sets off the primer, but being light & causing a “slow burn” is largely a myth. It’s a heavily debated topic(primarily in the rimfire community), with no way to actually prove it 100% for either argument. One side believes that velocities are affected by this. The other argument is that if the pin strike is enough to set off the primer, than a burn is a burn. I am of the belief that a primer which shows a very clear & pronounced audible tone, sounding like every other primer one’s heard, & having a well defined pin strike indent has experienced a complete & correct burn.

[sharpshooter]

I know it to be a fact, I've done the research and experimenting. You can believe what you want to.

[Dave Hoback]

Oh yes....your "evidence" is so overwhelming.

Indeed I can. Thank you so very much for "allowing" me that.

[olddav]

I’m with “sharpshooter” on this one.
As if he needs my support!

[Dave Hoback]

That’s fine, you’re allowed to believe someone devoid of any evidence simply by their word. That’s your right. I like researching & thinking for myself. Uh oh...I see you deleted your first post.

A weak primer strike causes NO FIRE or a HANG FIRE, which is a delay. But once it lights off, it lights off. So a person can “claim” the mysterious “slow burn” theory...but that’s all it is. A theory. No one, including Fred, can produce any evidence proving this. And “because I say so” isn’t evidence. Do a search & you’ll see the debate.

[olddav]

What ever you say Dave

[Dave Hoback]

I see what you did there. Well, imitation is a form of flattery. FOLLOWING suits some people.