Firing pin, springs, FTF.

[KMW1954]

I have suddenly run into a situation to where I am getting frequent FTF ina Model 11 that I have been loading and shooting with for more than a year. Now before you all start with primers not seated properly this has already been thoroughly gone through and eliminated as the problem. The one fact that has been consistent is that these unfired cases all measure .005"-.007" shorter after being chambered and struck. Never seen anything like this!

I have been using CCI450 primers of late and many of the fired ones show signs of cratering around the firing pin dimple while the FTF rounds all show very light strikes. Previously I was using CCI400 and they were cratering horribly and even had a few pierced. Not a high pressure issue because this would happen with even starting load charges. Also would not see this when fired in another rifle.

So tonight I ordered new springs, firing pin and wavy washer. This rifle has the new model one piece pin with 2 pc. spring.

[Dave Hoback]

KMW, try to find some kind of washer/spacer to preload the springs a bit more. Maybe another .060” preload… maybe a bit more? This has been an ongoing issue with the new setup & the consensus is the counter sunk hole for the spring in the BAS was machined too deep by Savage so the setup has insufficient preload.

[KMW1954]

I am aware it is an issue with the Axis and now thinking of this the pin design in the 11 is the same as the Axis. Will have to see what I can find for a washer or wait for the new springs to arrive. Still trying to figure out how I see metal flow on some primers and then the next one will be light and not fire.

[Dave Hoback]

The other thing I do regardless is debur/polish all the metal contact points. The inner edges of the bolt sleeve where the cocking pin rides especially, and inside the sleeve bore. Make certain the pin isn’t hanging up along the path.

If you can give me the inner/outer diameter numbers for a shim, I can machine one for you & mail it. I have Steel, Aluminum & Titanium plate in all different thicknesses. I just don’t have one of those firing pin set ups handy. Mine are the older adjustable pin style.

[Rocketvapor]

What measurement of the cases is giving you "these unfired cases all measure .005"-.007" shorter after being chambered and struck" ?
You didn't lose the third piece of the "springs" ? That's about 0.055".

Here are some quick measurements from one of my "New Type" bolts.

Dave, you're the machinist but I think a shim O.D. of 0.395" and an I.D. of 0.260" would allow for some BAS tolerance, and keep the shim over the full spring diameter, and keep the indicator from dragging on the pin.
A pair of 0.025" - 0.030" thick shims would allow a degree of adjustment.

[KMW1954]

No the small washer between the springs is present. All fired cases are coming out at expected lengths while all unfired cases are coming out shorter than length sized to at base to datum line at shoulder. Creating excessive head space.

[pdog06]

So some of them failed in a different rifle as well? That seems to eliminate a rifle issue in my book.
Seeing the pictures, that brass doesnt get shorter by not even being fired. It had to be shorter before you chambered it. But based on those measurements, are ALL of the FTF cases close to the shorter distance? Or are some of them the length of the one that fired? Did you measure the loaded rounds after sizing or before they were chambered? Were they all the same or some king and some short?
I feel until you figure it out, you need to measure before sizing, after sizing, after loading, and after chambering/firing to give you more of a basis to go off of.

Also, I’ve read on other forums of a guy having an issue with FTF with cci450’s in cold weather(20-30’s). Not sure what conditions you were shooting in? Their rifles were not Savages. Atleast 1 was a Tikka. Did it in both rifles. They switched back to cci400 and the issue went away.

I too would like to see what it ends up being. We may all run into this issue one day. It is how we all learn.

[sharpshooter]

I'll say it again.....insufficient impact energy. Those cases could be .015" short and still go off with the correct impact energy.

[South Prairie jim]

I'll say it again.....insufficient impact energy. Those cases could be .015" short and still go off with the correct impact energy.

This is worth repeating.

[KMW1954]

I'll say it again.....insufficient impact energy. Those cases could be .015" short and still go off with the correct impact energy.

So then please explain how this issue can be so intermittent. This same rifle just fired 45 rounds w/o a single misfire. Even though I have now purchased a new firing pin, both springs and the tension washer no parts have been changed. I just fired 25 of the same primers, from the same lot, CCI450 and then another 20 Remington 7 1/2.

[charlie b]

Do you still have the 'original' ones that still did not fire in the model 10? If so, when you pulled the bullets did you check to see if the primers had gone off?

This is one of those weird problems.

[KMW1954]

I too would like to see what it ends up being. We may all run into this issue one day. It is how we all learn.

So was able to do some quick measurements;
All brass was measured base to datum before loading and after loading to a length of 1.462". Any and all that didn't meet that was culled out.
All fired brass from this lot measured from base to datum, 1.462" - 1.464"
All pcs that FTF measured 1.454" - 1.457"

These are all from the same lot and now have 9 more that did not fire. They too will be fed into the Model 10 to see if they fire.