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.
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.
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.
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.
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.
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.
Just checking on the 'Key Ring' washer :)
Sounds like short new brass.
I get the same with Nosler brass for a 22N. About 0.005" short.
Pin still fires them and reloads are proper length.
Pin protrusion might be on the short side.
Correcting pin protrusion with the 'New Style' pin might be a problem.
Dave be the expert here.
Expert? Maybe EGGSpert!Originally Posted by Rocketvapor
No, I’m just a well informed hobbyist!
But is does sound, by what the OP is explaining, it is headspace. But what ammunition is this? One kind, multiple kinds? I ask to try to narrow down whether it’s the brass in this ammunition specifically, or is it in fact the rifle’s headspace.
As for the firing pin protrusion, the 1-piece pin complicates as it lacks adjustability. There are two options, either filing, sanding the pin tip or making a small washer to stop the pin at the appropriate protrusion. However, I would measure & be absolutely certain before doing anything(especially removing pin material.) Any way you can post a picture of the bolt face showing pin protrusion? Also how is the play between firing pin diameter and the pin hole in the bolt head? Excessive play is the most notable cause of cratering. And the pin radius can affect the entire operation including FTF. The protrusion should be around .035” and the pin tip Radius should not extend below the bolt face surface. I tend to post a picture of my bolt head & pin protrusion. It’s just under .035” and has optimal tip Radius.
Just to clarify, this is not new brass and it is not short brass. This is all Hornady brass. This has been fired in this rifle 3 times and processed and reloaded by me to be used as target match ammunition so it has been thoroughly inspected and measured to be fired in this rifle. So indeed it all has been head spaced to this rifle. Primer pockets have also been uniformed and measured and primer seating also measured. Every round that has failed to fire has measured .005"-.007" shorter than the loaded length measured to the shoulder datum line. As was just brought up by my mentor I have not tried to chamber this and then eject and measure before firing. All primers have also been measured after FTF and all still measure the exact same as before firing. Primers have not moved.
So I can understand the light primer strikes and possible weak springs but I cannot account for the shoulder movement which is only appearing on the rounds that do not fire.
Sounds frustrating.
Primers don't seem to be in question.
Just cases that don't fire and lose length?
Does sound like you maybe need to make a few dummies and find the cause.
Maybe size then chamber check before loading. I know, sounds like work
Fired rounds will likely be blown out to the chamber. They come out fired and the same length as loaded?
Is this brass getting shorter?
OR
FTF brass not being blown out?
You know people complain about the Savage action not being as smooth as the Rem 700.
Bet they can't bump shoulders 0.005" and not notice it. :)
(OK, a little humor, sorry)
So after being chambered, FTF and extracted, the cartridges that FTF are shorter than the other reloaded cartridges that weren't chambered ?
I'm guessing your just neck sizing and not full length sizing ?
I would thoroughly clean your die set and see what happens.
SJC
Lack of impact energy caused by lack of travel. Do yourself a favor and replace the firing pin assembly with the old adjustable type. You will also need a cocking sleeve and solid bolt assembly screw.
"As long as there's lead in the air....there's still hope.."
Thanks but in my very first post I stated I already hace on order a new pin, springs and washer, so I will see who that changes things.
The FTF cartridges are shorter than they were before being chambered and fired. They shrink.
All cases are full length sized and measured for head space and OAL before loading.
There seems to be two things being discussed.
Firing pin/spring to fix the FTF, and
Something shortening brass causing it not to fire.
Shrinking brass? Run sized but unprimed brass through the chamber.
Keep doing this until you find a shrunken piece.
Somehow I don't see pulling the trigger, weak pin fall, not denting the primer, causing a cartridge to shrink.
Playing with the firing pin to get it to FIRE shortened cases doesn't sound all that SAFE to me.
Hmmm… I’ve never heard of a case shrinking. Ever. I don’t think it’s scientifically possible. 60KPSI pushing out from everywhere on the case. Is there a chance measurements were overlooked for these few cases?
They just don’t shrink. They only grow. Again, that I’ve ever even heard of.
Sharpshooter is right about the firing pin. Same reason I recommended it as well. (Just in a more gentle fashion, LOL!) It’s doubtful you will see any difference at all with the 1-piece replacement parts.
Yes the question is more or less is it the Pin assembly/springs or a head space issue causing the FTF!
IF headspace is excessive, long cases could still fire. Short cases probably not.
5 to 7 thou short could be the difference between firing and not firing.
Headspace could also account for primer cratering.
Dummy rounds or unprimed cases until you find what is causing shrinkage.
Of course, I don't believe it or understand it but it is happening. I have already been though this complete process twice already measuring each piece before and after. Long ago, 1980's I worked as a machinist making valves for nuclear power plants so I think I know how to use measuring devices.
I have pages of notes and pictures of this I can send you if need be. I cannot explain why these cases are being crushed but it only happens with the cases that do not fire. Every case that fires either remains the same length or it stretches slightly. Yes I have remeasured those also.
That has already proven unsuccessful. Tired of wasting costly primers.
If your cases are the issue, it's your reloading practices that are the cause of the FTF, not the rifle.
As others have stated, brass doesn't just magically get shorter without the user doing the shortening.
Clean your die set, Start with fresh brass, make sure you size all of your brass at one time and see what happens ?
Take all of the measured shorter brass and toss them.
SJC
Brilliant suggestion, only this has already been done two week ago, Also standard practice is that all brass is sized as a complete lot at the same time. Have already been through all this with a friend and fellow Bench Rest shooter from start to finish twice. Reason I came here and presented this is because he is unfamiliar with Savage rifle and their Firing pin system.
There must be something missing in this online discussion.
Being there seems to be the real solution and I'm sure you will post back what you and your friend find.
Best of luck and be safe.
RV
There is something missing, the understanding that magically shrinking cases are being loaded into a rifle and the rifle is being blamed for the FTF.
Rifle brass doesn't shrink on it's own.
I wish you luck on your quest to find the answer to the mystical brass shrinking issue and hope you post the spell it took to remove the hex on your brass.
SJC
Now, now shootsWhile I think perhaps something is being overlooked(we all do it from time to time), KMW has been loading 223 in his Savages for several years. I certainly do not doubt his understanding & ability in measuring. I know it’s meant to be funny…but, maybe simmer down on the condescending remarks? I mean… it is Christmas
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