Misfires.

[CLUTCHfan]

Very new to all of this, so please bear with me.

I took up deer hunting again after 10 years of nothing but waterfowl, and decided to use my Rem 700 ltr for a long weekend in some spots that rifle hunting is allowed and that I might have been shooting to 300yds. I picked up a couple boxes of Hornady SST in .308, and went to the range to dial in. Set up my chrony, aimed over the top, and click. Ejected the shell, and there was a dimple in the primer. Loaded another round, and the gun fired. Loaded another one, and click again. Next one, bang. I loaded 14 rounds, sighting in, and a total of six were misfires. They seemed to alternate up until the last three rounds, which all fired. It's factory ammo, out of a factory rifle, and I bought the gun used quite a while back, and have never had this problem. I am assuming it's not the ammo. I'm thinking that maybe it has something to do with the bolt.

What course of action should I take, or where should I start, to figure this out?

 

[Capt RB]

If the gun was left cocked for a long period the firing spring may have taken a set to reduce the amount of striking force. You can replace or have replaced the spring. You can replace the whole firing pin assembly from Tubb speed lock or Gre Tan Lite firing pin kits.
Here is an article on springs and how guns run on them
http://www.davidtubb.com/catalog/view/theme/davidtubb/pdf/product_information/cs_springs.pdf

 

[CLUTCHfan]

Great! Thank you very much.

 

[justgoto]

If the gun was left cocked for a long period the firing spring may have taken a set to reduce the amount of striking force. You can replace or have replaced the spring. You can replace the whole firing pin assembly from Tubb speed lock or Gre Tan Lite firing pin kits.
Here is an article on springs and how guns run on them
http://www.davidtubb.com/catalog/view/theme/davidtubb/pdf/product_information/cs_springs.pdf

Every thing in that link you've posted leads me to believe that "compression cycles" are the deciding factor as to how long a spring lasts before needing replaced.

Longevity
How long should a spring last? Obviously there many factors that determine how many compression cycles a spring can withstand before it loses its efficiency. Here are a couple of points to consider:

and

We further stated that the spring should lose no more than a maximum of 7% efficiency through 1,000,000 compression cycles although we felt that the useful life would ultimately be somewhat higher (2,500,000 cycles) with an actual loss of efficiency in the 3 to 4% range in the first 1,000,000 cycles.

It states that when you compress a spring to its "yield point" it takes a "set." But it doesn't state that being compressed "for a long period" will "set" more so than with a quick compression cycle.

Another major factor is the first "yield point" of the material. This is the point at which the spring and material will yield to outside pressures and not fully relax. That is to say, when a spring reaches and then exceeds its first yield it will no longer come back toits pre-compression length

To answer the OPs question:
I'd try dismantling the bolt, and thoroughly cleaning all the components before buying things.

 

[CLUTCHfan]

Ok. Thank you.

 

[LoneTraveler]

I been there. My dad had a Rem. 722 in 222 Rem. He said I was not loading his shells right. He had problems with the firing pin dent blowing out in the primer. And misfiring. With his passing I inherited the gun. I had the same problem and the gun would only shoot 2 inch groups at 100. Me and a Gunsmith buddy changed the spring to a new 700 Rem. Short action main spring. The rifle quit popping the holes in primers, misfiring and went back to shooting tight groups. Another thing that I have seen at the range is people will not get the bolt turned down into complete battery and the cock incline will pull the bolt down into battery and soak up firing pin power causing misfires. Good Luck in finding the cause.

 

[Garycrow]

Try different ammo first, don't assume it's not the ammo.

It's actually not that uncommon in factory ammo, sometimes a rifle will have a little excess headspace and one brand of ammo will be a little on the small size for SAAMI specs. The tolerances stack and that brand ammo will give an occasional misfire. Sometimes the factories produce bad batches also. In years past I've had lots of misfires with remington ammo in several different rifles. That's why I don't ever use remington primers in my handloads.

Try some federal ammo, federal primers are very sensitive and hardly ever misfire.

When trying to figure out where to start, start at the beginning. That's the ammo.

 

[CLUTCHfan]

Really appreciate the replies. I'll go back to the Federal Gold Match ammo I normally shoot out of it and see if that makes a difference. I'll be reloading in a month or two. Sure it wouldn't hurt to take the bolt apart this weekend and clean it really well anyway. I actually ordered a factory firing pin spring since I was already placing an order to Midway and it was $6. Might as well put that in while I have the bolt apart. Try an cover as many bases as I can.