New build problem - ignition issue

[tiny68]

I think I would also get a No-go gauge as well. Sorry, but the scotch tape thing, to me, is soooo un-precise it's not funny. In addition, the tape will compress, might be a little might be a lot.

Other than that, I agree with Mach 2. Cut variables as much as possible, and eliminate them one by one. One thing for sure about media being in the primer hole. You most likely will NEVER find it on one of your FTF cases, because when you punch out the old primer, you wil also punch out the media interfering with it, if there is any.

Might try borrowing a no-go gauge and checking it. With the tape method, seems like every thread I have read on it says it (the bolt)should not close on TWO pieces, but again, not my preference. To me it's like using a 5/16" wrench on a 10mm bolt. It might work this time on this bolt, but.....

In defense on all of us that use a go-gauge and then a piece of Scotch tape - if you shoot your reloads exclusively you can set the chamber to whatever you want. If you want to fire factory ammo then you have to be picker about meeting an exact spec. Never have had an issue with the tape method in more than 20 barrel swaps. The tape has a known thickness. The process I use is even a little simpler. I screw the barrel down firm against the go gauge. I then make a reference mark on the barrel with a Sharpie. I have a piece of masking tape I put on the action with marks for every 1/64 of a turn. I then back the barrel off 1/32 of a turn which is 0.00156" and tighten the nut. This give me a tight crush bolt closure with a single piece of tape on the go-gauge. I use the tape just to verify everything worked to plan.

If you feel better about it, then us both the go and no-go gauges. From my understanding, the difference between go and no- go gauges vary between 0.003 and 0.005". You want the headspace some where in the middle. I can live with the additional 0.0015" to the go-gauge for my work. Yes it may be a little tighter than some, by again if you reload and size your brass to your chamber the. It doesn't matter.

Tim

[Dennis]

From my understanding, the difference between go and no- go gauges vary between 0.003 and 0.005

I understand the variance between gauges could be greater than what you stated.

JMO, Dennis

[sharpshooter]

That small difference in headspace won't make any difference if the impact energy is there, nor will improperly seated primers. If that little make the difference, you still have a lack of energy.
I once performed an experiment with a .223 to see how much excess headspace it took to make something bad happen. I moved the barrel a quarter turn out (+.012") and cartridges still went off with no case separations. When I got to +.016", they would no longer fire.
The FP protrusion was set @ .035". Although the cases didn't show a head separation, they were stretched beyond limits and were promptly discarded. If they had been sized and fired a second time, it would have trashed them.

[Dennis]

I still feel he has a sear problem, or internal bolt problem.

If the sear is binding in any way, that's all it takes.

Dennis

[BillPa]

I still feel he has a sear problem, or internal bolt problem.

If the sear is binding in any way, that's all it takes.

Dennis

That was my thinking also, why I went the direction I had.

Going by his case and gauge measurements he should have been able to ignite even those dastardly hard to light CCI primers. I use BR2-4s about 50% of the time without a hiccup. To top things off, if the extractor engages the cartridge extractor groove when chambering a round headspace/head clearance becomes a non issue, the extractor prevents the cartridge form moving forward. Its how some Bozo (name withheld) successfully fired a 308 Win round in a 280 Improved chamber!

Dunno.

Bill

[tiny68]

Fred, Dennis, and Bill,

I think you guys are correct that something is still binding. I will size some brass correctly and waste some primers to correct more data. I did fire the 10 rounds of factory yesterday with no issues. Reliability is important since this is my son's first center fire. I will pop off 25-50 primers and see what I get. Tim

[Dennis]

FWIW, I was installing my action in a new stock, just bedded. All parts new. When I was inserting the action in the stock, I noticed my sear moving as the action was almost in place. I found the spot on the stock it was hitting, the dremel took the excess off the stock, I had no movement with my sear when I reinstalled the action.

I still have to sight it in and find it's load, but at least I took care of this issue first.

Dennis

[tiny68]

Well I know I had Clarence issues with the sear when I first bedded the action. It wouldn't even cock when I started. I will check it out. Tim

[Dennis]

Well I know I had Clarence issues with the sear when I first bedded the action. It wouldn't even cock when I started. I will check it out. Tim

Tim, after stating this, I would definitely inspect the complete trigger for clearance issues, mainly on the right side.

When I cleared my stock with automotive clear, I ended up with too much paint on the right side inletting and even around the tang area. After I realized what the problem was, I could see it. I had "fine" scratches where it was too thick. I had to look close. The dremel took of the extra thickness and everything works fine now.

[243LPR]

Are you full length sizing or neck sizing,don't remember seeing that asked. If all you have is a full length die just size enough to fit your chamber.

[BillPa]

I agree Dennis, why I suggested trying to touch off a few primed cases with it out of the stock. That would have at least eliminated the stock from the list of possibilities.

What I was seeing was inconsistent primer impact depth but it doesn't explain why the factory ammo worked.

Dunno.

Bill

[tiny68]

I had a few free hours so I made it back to the shop this afternoon. Started with taking the 10 Win SuperX brass that fired at the range and knocking the primers out with a deprimer die without any resizing and seating fresh primers. 3 misfires out of 10. I took a picture of the misfired primers.

Misfires:
http://i159.photobucket.com/albums/t151/tiny68_photos/fired_zpsb1870345.jpg (http://s159.photobucket.com/user/tiny68_photos/media/fired_zpsb1870345.jpg.html)

Compare to 3 that did fire:
http://i159.photobucket.com/albums/t151/tiny68_photos/mis-fires_zps1456371d.jpg (http://s159.photobucket.com/user/tiny68_photos/media/mis-fires_zps1456371d.jpg.html)

I replaced the primers in the 3 that did misfire and tired again. 2 of 3 misfires. I pull the stock and reprime the brass. All 3 misfire. I am marking the sear movement with a fine tip Sharpie on the action. I can't see any difference between sear movement with fires and misfires. Confused again...

I strip the bolt again and make some new measurements.

Spring compression @ 2.600" per Fred's recommendation:
http://i159.photobucket.com/albums/t151/tiny68_photos/Spring_zps6aaec01e.jpg (http://s159.photobucket.com/user/tiny68_photos/media/Spring_zps6aaec01e.jpg.html)

I remeasure the distance to the boltface:
http://i159.photobucket.com/albums/t151/tiny68_photos/Boltface1_zps523eccc6.jpg (http://s159.photobucket.com/user/tiny68_photos/media/Boltface1_zps523eccc6.jpg.html)
http://i159.photobucket.com/albums/t151/tiny68_photos/Boltface2_zps2be7fe86.jpg (http://s159.photobucket.com/user/tiny68_photos/media/Boltface2_zps2be7fe86.jpg.html)

And then with the firing pin:
http://i159.photobucket.com/albums/t151/tiny68_photos/Boltface3_zps85cf5ad2.jpg (http://s159.photobucket.com/user/tiny68_photos/media/Boltface3_zps85cf5ad2.jpg.html)
http://i159.photobucket.com/albums/t151/tiny68_photos/Boltface4_zpsfe2cf051.jpg (http://s159.photobucket.com/user/tiny68_photos/media/Boltface4_zpsfe2cf051.jpg.html)

I measure the firing pin protrusion at 0.061", which was what I increased it to from 0.035" when I had this problem with the original assembly last year.

Inspection of the firing pin reveals a wear pattern (shiny marks) on one shoulder of the pin:
http://i159.photobucket.com/albums/t151/tiny68_photos/Firingpin1_zpsd5a02b8d.jpg (http://s159.photobucket.com/user/tiny68_photos/media/Firingpin1_zpsd5a02b8d.jpg.html)
http://i159.photobucket.com/albums/t151/tiny68_photos/Firingpin2_zps3705dd2f.jpg (http://s159.photobucket.com/user/tiny68_photos/media/Firingpin2_zps3705dd2f.jpg.html)

I thoroughly clean the firing pin and bolt tube with mineral spirits and a brush. Grease the firing pin (something I haven't done in past assemblies - only a few drops of oil). Re-assemble. Test again test without the stock. 3 mis-fires.

What the heck?

I go back and start looking over the components. I look at the primers again. They are brass colored on the inside. These aren't my Fed 205M - which are red on the inside. I break out the magnifier and I see the mark - these are CCI - BR4s. OK. So what. What difference would that make. For the heck of it, I go over to my benchrest box and pull a tray of 205M I shot several years back in my 30BR. Re-primed with the 205Ms. 3 fires. Reprimed again with 205Ms. 3 fires.

I this point I am mad that I mus-identified the primers to start with. If it turns out to be bad primers, these with be my first primer failures ever. I will stay that I purchased these CCI BR4s when I built my oldest son 223 5 years back. I didn't anything else at that time that use small rifle and that was what Gander Mountain had in stock. They work fined back then.

I will go out tomorrow and check with more 205s. If successful I will reset the firing pin protrusion back to 0.035".

Very frustrating.... Tim

[sharpshooter]

Tim, the 2.600" figure is just a ballpark measurement, it can be tweaked from there. Try this: re-adjust you FP protrusion back to .035", give or take a few thou. Re-adjust the compression length to 2.575" or thereabouts. This should give you about another .050" travel.

[tiny68]

I know I have asked this before but have forgot: what are the threads on the firing pin? Tim

[floydboy]

+1 what sharpshooter just said. Don't get too frustrated Tim. I don't mean to sound like an expert because I'm not but I had the exact same problem a few years ago. Spent a week on it off an on. Blamed it on everything I could think of. Was ready to take it to a smith I was so aggravated. Finally just gave up and started on the bolt from scratch. In my case Firing Pin compression was off. Somehow I had moved it in all the fooling with it. Not saying you changed yours or you can't use a set of calipers but you just need a little more "pop" if you will. Primer cups not only need to be hit hard enough to dent them the right amount but need it to happen with the correct amount of sudden impact. In my case I was soooo surprised. I was only a tiny amount off and suddenly all my primers starting firing. I agree with sharpshooter.....2.6 is a good place to start.

Good luck....Floyd

[Dennis]

Tim, it may be something so simple it will hurt you when you find out. Personally, I would have boxed it up and sent it to Sharpshooter and let him put his talented hands to work. JMO Sometimes 4 eyes are better than 2!

The answer is YES, I have become so frustrated with one of my rifles and did just the above. It happens sometimes. Sharpshooter found the problem as soon as he put his hands on it. I learned one heck of a lesson and wasn't even looking in the area where he found the problem. That was 3 years ago and the rifle is shooting as good as when he sent it back. The problem was very similar to what your experiencing.

I am watching now, because I am wanting to know what's up probably more than you do.

Good Luck,
Dennis

[tiny68]

Deniis,

Had this been a rifle for myself - I personally would have would have sent it off last year. My son, 10 at the time, helped with the bedding, refinishing the stock, barrel install, etc. This is his rifle. Pride thing.... But I have to figure this one out with him. He even took the pictures last night and helped with the measurements. I guess it has been hard for him to look at it for a year and have yet to put a round down range. We have had some family illness that made our hobbies go on hold. Such is life. I can't figure it out soon I will get a call tag. Thanks for the advice. Tim


Tim, it may be something so simple it will hurt you when you find out. Personally, I would have boxed it up and sent it to Sharpshooter and let him put his talented hands to work. JMO Sometimes 4 eyes are better than 2!

The answer is YES, I have become so frustrated with one of my rifles and did just the above. It happens sometimes. Sharpshooter found the problem as soon as he put his hands on it. I learned one heck of a lesson and wasn't even looking in the area where he found the problem. That was 3 years ago and the rifle is shooting as good as when he sent it back. The problem was very similar to what your experiencing.

I am watching now, because I am wanting to know what's up probably more than you do.

Good Luck,
Dennis

[sharpshooter]

Tim, the thread on the firing pin is 1/4-28. Each quarter turn equals .009".

[tiny68]

Tim, the thread on the firing pin is 1/4-28. Each quarter turn equals .009".


Thanks Fred - I need to write that down. To go from 0.061" back to 0.035" - 3/4 of a turn should do the trick. I will try to get back in the shop tomorrow night. Tim

[tiny68]

Back in the shop tonight.

I took the Win Super X brass (factory ammo) that had fired before. Decided to do a primer comparison before changes. No stock. CCI BR4s - 10 out of 10 misfires. Fed 205 (freshly opened box) - 10 out of 10 fires. Never knew there could be so much difference in a primer. I just guess is the thin cup Fred mentioned before.

Disassemble the bolt and make recommended changes. Adjust firing pin back to 0.035" protrusion. Adjust spring compress to 2.560". Clean, lube, and re-assemble. Fed 205s - 10 for 10 fires. CCI BR4s 9 for 10 fires! Changes definitely where an improvement in the primer strike - all nice consistent and look deep enough - good crater.

Restocked. Fed 205s - 10 for 10 fires. Switched back to the old LC brass that oversized by 0.004". 10 for 10 fires with Fed 205s.

New Laupa brass came today. I am going to pull my bullets on the ladders I have already loaded with the CCI primers and chuck them in trash. Fed 205s all the for me. I am not quit sure why the CCI Br4s are so much pickier about everything being set perfect. With the one misfire I got with the new firing pin and spring compression settings - I am just not going to mess with them.

Hopefully I can finish working up the load and get junior in the drivers seat soon. Once I get the load worked up I will post some pics of the rifle. It is a sweetie - NRA youth stock we found, SS LA action w/ SSS T&T job, SSS Competition trigger (set as high as it will adjust for now), and a 223 sporter barrel cut do to 17". Bushnell 4200 Elite 3-9x in Burris Signature Zee Rings.

Thanks, Tim