Light primer striks, MkIII

woody57 · Post by **woody57** » Mon May 05, 2014 10:37 pm

My MkIII has over 20,000 rounds thru it and lately I am getting light strikes on the primer. This will happen about once in a 100 rounds of CCI SV and with
SK Standard plus it happen so much I do not like to even practice with it. I have the original Main Spring and recoil spring. Is it time for them to be replaced or this there another problem I should be looking at.
Thnaks, Miland

greener · Post by **greener** » Mon May 05, 2014 11:29 pm

I don't think 20k would cause much of a problem. I'd try thoroughly cleaning the firing pin, channel and the bolt face. If that doesn't help replace the fp and recoil spring?

woody57 · Post by **woody57** » Tue May 06, 2014 1:02 am

Thanks Green, I did do a good cleaning of the firing pin and the firing pin rebound spring was in good shape. If I replace the firing pin would a Volquartsen a good way to go?

Post by **Bullseye** » Tue May 06, 2014 4:01 am

Since you've cleaned out the firing pin channel and pin you may want to do an extreme cleaning of the chamber. Those lighter target cartridge can have seating issues when the chamber gets fouled. Light primer strikes is the symptom you will see if the cartridge case rim is not fully flush against the breech face.

R,
Bullseye

blue68f100 · Post by **blue68f100** » Tue May 06, 2014 8:56 am

May want to check the main hammer spring for bind. Since it takes special tooling to remove, just put in a vice so you can push down on it. Add a drop of oil to lube it helps too.

What Bullseye said happens a lot. If mine starts acting up that is one of the first things I check.

woody57 · Post by **woody57** » Tue May 06, 2014 9:50 am

Cleaning the chamber was one of the first things a friend suggested. I used a 25 cal bronze cleaning brush with Hopps bore solvent. It also looks clean. When a round fails to fire I can put it back in and it will fire. What would be your method of extreme cleaning?

blue68f100 · Post by **blue68f100** » Tue May 06, 2014 1:59 pm

For the chamber (only) I turn the brush with a drill and gun solvent of your choice. The best gun solvent I have ever run across is Butches Bore Shine. You would be surprised what it removes after Hop#9 left behind.

My normal cleaner is just Red's gun solvent. If I have area that does not clean up I go to Butches.

I only detail clean when I start having problems, Normally the LCI will start to stick around 2500 rounds. When this happen you will start miss fires. Bolt will not go all the way forward..

Post by **Bullseye** » Tue May 06, 2014 5:40 pm

Sometimes what happens is the bullet tail splatters little lead deposits as it exits the casing, causing a small ring to grow inside the chamber. This ring is hard to detect with the naked eye and it grows with use. The ring ends up right where the case mouth is causing the case to set back over time. This set back moves the rim away from the breech face causing the light strikes, or what appears to be a light strike by the firing pin dent. Actually what is happening is the firing pin is hitting the cartridge with plenty of force but the cartridge rim absorbs the energy as it is moved forward toward the breech face. I spin or twist a bronze bore brush in the chamber taking care not to extend the brush into the rifling grooves. It can take some work to get all the lead remnants out of the chamber.

R,
Bullseye

greener · Post by **greener** » Tue May 06, 2014 8:57 pm

Imanaged to get water into themainspring housing a while. Back. The rust caused ftf's and light strikes. You can remove the mainspring without a special jig, but it is a pain. Check the topp of the mainspring housing for dirt, debrie, crap and corruption. Try to rinse it with your favorite solvent. Look at the solvent as it drains offthe washes by draining to a clean. Paper towel. If you don't see anything, you probably don't have. A problem with the MS. Try, if you can find it, several types of ammo. You have problems with one type and not another. If cleaning doesn't change that, it may be the ammo.

woody57 · Post by **woody57** » Tue May 06, 2014 9:34 pm

Ok I will get more aggressive with the chamber cleaning and see how that goes.
Thanks for the help!
Miland

woody57 · Post by **woody57** » Sun May 11, 2014 10:37 am

I gave the MKIII a really good chamber cleaning. I started with Hopps bore solvent with my chamber brush, then then I used JB bore cleaner on my jag and worked it in real good, used the chamber brush on a drill to remove any lose matter. Like magic when I went to the range yesterday I had no problems. Thanks for the help guys, you are great!
Miland

Post by **Bullseye** » Sun May 11, 2014 7:29 pm

Glad to hear your pistol is running well again!

R,
Bullseye