SRP and firing pin springs

[Hengehold]

Question: is anyone having to increase the strength of the firing pin spring when using small rifle primers (SRP)?

if so, what action are you using?


Background: This weekend I scored for a shooter using 308 with a SRP and CCI primers in a Barnard Model P action. Weather was 30-50 degrees. He had several light primer strikes that resulted in a failure to fire. Failure rate was about a 40%. I talked with another shooter at the match that was having the same problem with the Barnard Mod P action and SRP in a 308. Apparently Barnard has come out with a stronger firing pin spring to replace the factory original and that is a permanent solution. The stronger firing pin spring can also be used with LRP so it is a one time swap and done. I am wondering if this is unique to Barnard Model P actions for some reason.

-Trevor

 

[Bob3700]

Question: is anyone having to increase the strength of the firing pin spring when using small rifle primers (SRP)?

if so, what action are you using?


Background: This weekend I scored for a shooter using 308 with a SRP and CCI primers in a Barnard Model P action. Weather was 30-50 degrees. He had several light primer strikes that resulted in a failure to fire. Failure rate was about a 40%. I talked with another shooter at the match that was having the same problem with the Barnard Mod P action and SRP in a 308. Apparently Barnard has come out with a stronger firing pin spring to replace the factory original and that is a permanent solution. The stronger firing pin spring can also be used with LRP so it is a one time swap and done. I am wondering if this is unique to Barnard Model P actions for some reason.

-Trevor

What I have seen with the Barnard P action is that the end cap on the bolt works loose. This contributes to reduced firing pin spring compression.
Several shooters that experienced this were on my firing point. They actually were shooting 6mm BRs. and getting failure to fires. I grabbed their open bolts and turned the cap on the end several revolutions. Problem solved. This was at normal Spring time temps of 60-70 degrees F.
I might be inclined to put a dab of blue locktite on the cap threads to prevent the cap from backing off.
Just my experience.

 

[Stumpy1]

Hi Trevor,

The Barnard P has a bit of a pin-fall problem (in my opinion), coming in at just over 0.210". I believe this leads to poor/marginal ignition with small primers. I too have had primers not go off (Wolf, CCI, Rem 7.5's).

The heavy spring from Barnard helps a bunch, and a small (~.200" long) additional brass spacer at the chamber end of the firing pin adds mass to the firing pin, AND preload to the spring resulting in solid ignition over several years in my hands.

So, get the spring changed to the heavy and see how it goes for you.

Also, make sure the firing pin/bolt inside are clean and not gunked up with old grease which could slow down the firing pin in colder weather.

Hope this is useful,

Frank