Pin Problems?

[Vassal]

Hello,
I have recently finished a 300magnum build on a 110 that was trued by K Cram at Montour CO Rifles. All is good and the Shillen select seems to be doing a good job. HOWEVER,,,,,,,,,,,,

Roughly one of every three to four shots (I've only fired about 10 rounds) the primers aren't igniting. The primers are fine and have been stored well. The pin protrusion is about 56thou and the rounds always go the second time. They look like they were smacked good the first time also! I have put a wolf up power spring on the pin hoping to shorten lock time.

Any ideas? Is there some timing adjustment I'm not aware of????

Headspace is fine. a go guage is smooth and one piece of cellophane tape on the guage locks the bolt up high and early.

I also prep brass pretty well by uniforming primer pockets etc,,, zthe primers are all sitting normally.

I can't figure it out

Vassal

[stangfish]

Try putting a piece of tape on cases that the primers are not ignitng. You may have some brass that varies. Just a thought.

[Vassal]

I weight sorted the brass and did alot of prep work,,,I hope its ok but it is Winchester. OF COURSE there's no easy way to measure the "headspace" of the brass itself. This is my first experience with a belted case, I'm beginning to wonder,,,

[stangfish]

Did you try the "bad" cases with tape just like you did with the go gauge? If the bolt closes on the ones that did not fire with tape on the head then that may be your problem

[82boy]

Hello,
The pin protrusion is about 56thou and the rounds always go the second time. They look like they were smacked good the first time also! I have put a wolf up power spring on the pin hoping to shorten lock time.
Any ideas? Is there some timing adjustment I'm not aware of????
Vassal

Well to start with why did you change the spring in the rifle? The Savage factory spring is plenty stiff enough to ignite any primer ever made. Placing a heavier spring in the gun is at best a band aid fix for an ignition problem. Tony Boyer say it best in his book, changing the spring out in hope to gaining ignition is like having a door out of alignment on your car, instead of putting it back in alignment you just slam the door harder. This is what you are basically doing with putting in a heaver spring. Trying to gain lock time on a Savage action is a waste of time, as the Savage action has one of the fastest lock time out of all the actions made.

You never mention how much firing pin travel you have and this is the most important thing. Your firing pin protrusion is too much, and you are loosing travel because of it. Firing pin travel needs to be at 35 thousands to 40 thousands max. Do your self a favor and put the factory spring back in, and set the firing pin protrusion to the above.

After that if your still having ignition problems, you need to send the gun off to a Gunsmith that understands timing. The problem could be caused by the shape of the firing pin tip, (Caused by blanking primers, and other things.) you could have a problem with short travel of the firing pin, the bolt de-cocking as it is closing.

Did you make any other modifications to the gun? Such as change out the trigger, ETC. Did you fire the gun prior to changing out the spring? Did you have problems before changing parts?

[skoger]

These would not be CCI primers would they? Had the same thing happen to me with a Savage, and a custom Mauser I built, both times was same 1000rd box of CCI primers. Both rifle had extra heavy firing pin springs, would barely dent some of them, some would fire second time. Loaded Fed. and Win primers, no problem. CCI told me to send them back, they had this problem happen pretty often the way they talked. I threw mine in the garbage and never looked back. Have neve had the same problem with any of my rifles, since then.

[82boy]

I have burned through thousands of CCI primers, and never once had a problem. Most long range Benchrest shooters are using CCI 450 mag primers, and I can not say I have ever heard of any of them ever having a problem with them.

[Vassal]

Well to start with why did you change the spring in the rifle? The Savage factory spring is plenty stiff enough to ignite any primer ever made. Placing a heavier spring in the gun is at best a band aid fix for an ignition problem. Tony Boyer say it best in his book, changing the spring out in hope to gaining ignition is like having a door out of alignment on your car, instead of putting it back in alignment you just slam the door harder. This is what you are basically doing with putting in a heaver spring. Trying to gain lock time on a Savage action is a waste of time, as the Savage action has one of the fastest lock time out of all the actions made.

You never mention how much firing pin travel you have and this is the most important thing. Your firing pin protrusion is too much, and you are loosing travel because of it. Firing pin travel needs to be at 35 thousands to 40 thousands max. Do your self a favor and put the factory spring back in, and set the firing pin protrusion to the above.

After that if your still having ignition problems, you need to send the gun off to a Gunsmith that understands timing. The problem could be caused by the shape of the firing pin tip, (Caused by blanking primers, and other things.) you could have a problem with short travel of the firing pin, the bolt de-cocking as it is closing.

Did you make any other modifications to the gun? Such as change out the trigger, ETC. Did you fire the gun prior to changing out the spring? Did you have problems before changing parts?



I didn't replace the spring in order to increase ignition, that wouldn't make any sense unless the factory spring was weakened somehow. As stated, I replaced the spring in order to shorten lock time. Will it make any difference, who knows but it can't possible hurt.
I have about 56 thou protrusion right now I' guess I'll try to shorten it and see if that gets it. I can't quite reckon with how that would do it, but I can sense that it might.

Thanks for the help.

[82boy]

As stated, I replaced the spring in order to shorten lock time. Will it make any difference, who knows but it can't possible hurt.
Think again. Putting in a heaver spring is THE absolute worse things you can possible do to a MODEREN bolt action rifle.

Everything is a trade off, to gain something you must give up something. When you attempt to gain lock time by going to a heaver spring, the first thing you give up is it take more force to cock the rifle. The other thing you gain in going with a heaver spring is a hole new level of harmonics. Everyone I have know or have talked to have lost accuracy going to heavier springs.

Go ahead and try it and see if I aint right.

[ellobo]

On the CCI primer business. I once had a brick of small pistol primers that were oversize. The made an audible crunch sound when I had to seat them by really leaning on the press lever. When they were finaly seated they were flat as if they had been fired with an overload. Under normal circumstances I would not have used them but with an upcomming match in a few days I had no choice. Luckily they still fired OK. Right now I have a brick of large CCi's that have the same oversize problem, These I cannot even seat in thier pockets in .45's no how hard I lean on the handle of the loading press. My primer pockets are cleaned with a primer pocket brush and I have had no other problems with other makes of primers. I am glad to hear you have had no problems with yours 82 boy but I for one have decided I will no longer use CCi's

El Lobo

[northlander]

I have seen this problem before, the rifle primers were not fully seated. When you pull the trigger the energy that normally crushes the anvil and ignites the primer compound was being used to push the primers fully into the primer pocket. The results were several misfires. When fired the second time, most of the dented primers did fire. Just a thought but this certainly sounds like a similar issue.

Jim Briggs
NSS

[Vassal]

I have seen this problem before, the rifle primers were not fully seated. When you pull the trigger the energy that normally crushes the anvil and ignites the primer compound was being used to push the primers fully into the primer pocket. The results were several misfires. When fired the second time, most of the dented primers did fire. Just a thought but this certainly sounds like a similar issue.

Jim Briggs
NSS

I thought of that but I checked with a primer seating device and they are tight.

[Vassal]

Interesting, I have a similiar spring in my short action 6.5BPC and it shoots very well.

[jonbearman]

How are you sizing the brass and do you have a hornady tool for measuring the bump you need for smooth cycling of the bolt.Does the bolt close easy or hard? What type of dies are you using and how do you set them up.You can induce a headspace issue by oversizing.One way is to set the die up to touch and feel the cam over when operating the press.Take a fired case and back the die off about a turn and size to see if the case fits the rifle or you cant close the bolt.(do this with a fired case or two)Turn die down a 1/8th of a turn till the sized case fits the gun and the bolt closes with no tightness.Then measure with a feeler gage and see how much gap there is from the shellplate and the die bottom surface. Always use the same shell plate with that die.Basically when you oversize ,you squeeze the trigger and the firing pin moves the whole case forword and doesnt go off.The second time you already moved it forward and it goes off with the extra firing pin protusion.I hope this may help you.