Contender pistol, CCI 400 Primers and Misfires

[MrK.]

I've been working up a new load for my Super 14 Contender pistol in 7mm TC/U using 139gn Hornady SSTs, CCI 400 primers and H335 powder. I shot a 12 shot ladder back before Christmas which went well. I loaded up a couple of charge weights to test and headed out yesterday to see how they would group. The higher charge weight looked promising but the 3rd of the three failed to fire even after trying three times. Now this was my first misfire ever save my very dirty marlin .22 when I was younger. I chambered one of my current rounds after and it went off fine. When I got home and took the gun apart. After inspection everything looked fine but I went ahead and cleaned all of the grime off of the working parts with a q-tip and brake cleaner. I loaded 5 more rounds and headed back out this morning. The first of the five failed to fire but the other 4 did fine. I have always used Winchester primers in this gun but decided to try the 400s because I snagged a brick at Academy. I Gingerly pushed the primer out and re-seated it into a piece of 300 BLK brass and it went off fine. Anyone have any thoughts? I inserted pics of today's primer in the case and after I pushed it out, my firing pin protrusion and my 4 shot group from today (should have quit after 3).

 

[Link]

Hammer spring? Cost me a big shoot, long ago.

 

[Bill K]

The primer in the case looks, too me, like a very light load. One thing you might check is the headspace on you contender. Google Bellm's TC and read how he checks and improves headspace, for flush fiting of the cartridge in the action.

 

[C.E.Smith043]

I was thinking you may have set the shoulder back too far when resizing, primer not seated completely at the bottom of the primer cup, or hammer spring weak, also if you cut or uniformed the primer pockets, may have cut too much.

 

[mmcu]

I'd bet that you oversized your brass and have too much headspace.

TC Contender's and Encore's don't tolerate this at all.

 

[snert]

^^^^ This. Your previous sizing was just on the edge of being too much headspace. You fired it, resized it and the shoulder is pushed back a "scooch" (scientific term of measurement) too far. Back your die a 1/4 turn and size a fired case. See if it closes with a snap. If not, slowly wind die down, sizing till it just closes.

 

[drop_point]

Too much headspace/over-sized.

 

[MrK.]

Hammer spring? Cost me a big shoot, long ago.

This might be it. I know it's not a headspace issue as several suggested. I have already been down the headspace issue with this cartridge (check my posting history). These are newly formed cases but are all sized for a slight crush fit. I should have mentioned that in my OP. I think I may purchase some springs as well as a new firing pin they are pretty inexpensive and certainly cannot hurt.

 

[searcher]

This might be it. I know it's not a headspace issue as several suggested. I have already been down the headspace issue with this cartridge (check my posting history). These are newly formed cases but are all sized for a slight crush fit. I should have mentioned that in my OP. I think I may purchase some springs as well as a new firing pin they are pretty inexpensive and certainly cannot hurt.

If you are getting strong firing pin strike, because your primers do shoot well in other gun, that can usually only mean headspace issue. I'm thinking your "crush fit" may not be as sound as it may appear to be, allowing the case to move forward on firing pin strike. I'd measure the headspace on an unfired (loaded) round and compare it to a few of the "duds". If the headspace is a tad shorter on the duds, that is likely what is happening. I assume when you say "crush", that refers to feeling a bit of resistance when the bolt is closed? Are you certain your bullets are not jamming, giving you a false signal that you are getting brass crush?

 

[marchboom]

Do you have one of those hammer spurs installed? I had a misfire on mine after I installed one. The extra weight slowed down the hammer speed so it didn't hit with the necessary power.

If not that then my bet is the hammer spring.

 

[JSH]

If you’re 100% sure it’s not headspace………
Seat primers to contact the bottom of the pocket.
I have run thousands of CCI 400’s in my TC rigs. 9 chances out of 10 if. Had a problem it was something I did. I see lots of comments on hammer springs, personally only had one break in the last 40 years.

 

[HandgunHTR]

I had the same issue as the OP on a Gen1 Contender frame. Turned out to be a weak hammer spring.

It isn't a bad idea to replace the springs every few years, regardless. Small price to pay and it is fun to learn how these firearms work.

 

[marchboom]

I had the same issue as the OP on a Gen1 Contender frame. Turned out to be a weak hammer spring.

It isn't a bad idea to replace the springs every few years, regardless. Small price to pay and it is fun to learn how these firearms work.

I had the same thing happen. Never heard of a spring breaking but they do get weak. Good idea to change them every few years. Don't need it to not function when you need it.

 

[bozo699]

Everyone might be running 400’s with no issues but there designed for low pressure rounds like a 22 Hornet
Wayne

 

[Uncle Bruce]

If you’re 100% sure it’s not headspace………
Seat primers to contact the bottom of the pocket.
I have run thousands of CCI 400’s in my TC rigs. 9 chances out of 10 if. Had a problem it was something I did. I see lots of comments on hammer springs, personally only had one break in the last 40 years.

When you close the action with a round in the chamber do you have to kind of have to snap it shut or gently close it. If it doesn't take much effort then you may have maximum or excessive headspace.

Uncle Bruce

 

[MrK.]

I'm definitely sure its not a headspace issue. I measured the length (base to .33 datum) on 5 of my new reformed but unfired cases and 5 of my old fired cases (primers removed but not sized). My new cases average longer by .0015. I'm not really sure I trust my caliper to the .0000 place though. I also took the barrel off and put it into a soft vise. I dropped a newly sized case into the chamber. The case head is definitely proud of the barrel but all I know is it's less than .0015 because that's the thinnest feeler gauge that I have. I know I'm not jamming bullets because I can drop a bullet into the chamber, drop a case in behind it and close the action.

I'm betting that it is a weak hammer spring combined with the hammer spur mentioned above. I ordered some springs and a new firing pin and hopefully it solves it. I already got my shipping notice.

Thanks everyone for the input.

 

[Doug Casner]

CCI primers will make a weak firing pin spring worse. Doug