Fail to fire question

[Wyatt Smith]

My Winchester safari express 375 has been failing to fire way more than a comfortable amount lately, and I have some questions.
I roll my own ammo and CCI 250 and Remington large rifle magnum primers have both failed,I feel that eliminated the primers being the problem but I suppose it still could be. The FTF problem has happened with Norma Winchester and PPU brass. I’ve never had a FTF with my A square or Remington brass. Could it be the brass? Could the primer pockets be too deep and causing a high primer? I clean the primer pockets ever loading
Sometimes a second strike will ignite it and sometimes it won’t. I have a hard time believing three different lots of brass to have the same problem. I seat the primers in the exact same manner every time.
The only common variable is the rifle. It’s happened since it was new and I keep it clean. I’ve ordered a new firing pin spring, and the pin seems to come through the bolt far enough. Also the brass isn’t stretching bad so I’m assuming the headspace is ok.
Thanks for the help!

 

[sestoppelman]

If the primer pockets were too deep, you wouldn't get high primers, you would get low primers. Primers should be seated just a hair below flush or flush which is OK in a bolt rifle, not so much in a semi auto with floating firing pin.
Did you try an extra power FP spring yet? Perhaps you are sizing your brass too far down and pushing the shoulder back. I usually try to headspace off the shoulder even with a belted round just for this reason. You might try that.

If you have done all that and are seating primers properly, then sad to say headspace may well be the issue.

 

[Wyatt Smith]

If the primer pockets were too deep, you wouldn't get high primers, you would get low primers. Primers should be seated just a hair below flush or flush which is OK in a bolt rifle, not so much in a semi auto with floating firing pin.
Did you try an extra power FP spring yet? Perhaps you are sizing your brass too far down and pushing the shoulder back. I usually try to headspace off the shoulder even with a belted round just for this reason. You might try that.

If you have done all that and are seating primers properly, then sad to say headspace may well be the issue.

The extra power spring is on the way, and I do full length size the brass I will try that after the new spring( I’d try it now but I need to do some shooting to have brass to load). I guess if it happens after that I will get some headspace gauges.
Thanks!

 

[Hogpatrol]

I find the dud box full of light strikes. I would suggest changing the firing pin spring. I know match competitors that change the spring every season.

Edit: Pull the firing pin out and clean everything. Gunk buildup can cause light strikes.

 

[Hunter4752001]

. Gunk inside the bolt is a very common cause of light strikes. Remedy: Disassemble and clean.
. If the firing pin spring has become under strength then it needs to be replaced. Examining a light struck primer and a fired one isn't a reliable gauge of firing pin spring strength as the act of firing creates a deeper impact crater due to detonation. Simply easier to replace and thereby eliminate as a possible problem.
. If the case has been overly resized ie creating a headspace problem, then the energy of the firing pin will be absorbed moving the case forward in the chamber (or not reaching the primer at all). In this situation those cases which did fire should have significantly flattened primers (due to the primer partially backing out on primer ignition then being re-seated as the powder column ignites). Remedy: Visually examine fired cases and adjust dies if needed.
.If a primer is not seated to the bottom of the primer pocket then the energy of the firing pin will be absorbed as the primer moves forward causing it to fail to fire. Remedy: Seat the primer to the bottom of the pocket. Do it by feel.

 

[Opposite Pole]

Measure the depth of primer pockets, thickness of the primers and see how deep you are seating them. It’s possible primers are not seated deep enough.

 

[fourfive8]

Everyone has pretty much covered the "normal" possibilities. There are several so just have to use process of elimination to really pin it down to the culprit, otherwise there will always be doubt. And that doubt is no good...

The easiest to start with would be complete disassembly of the bolt and clean inside and out. Then lube the striker, spring and inside of bolt barrel with only a light coating of a dry lube like graphite.

Depending on how comfortable you are with DIY gunsmithing jobs, check for striker/firing pin impingement on inside of bolt where the pin "ricochets" off of or rubs hard on the inside of the hole or the spring is rubbing inside of bolt barrel - can be caused by bent pin or wrong spring. Check the firing pin protrusion when striker/pin is in fired, forward position- should be about .050-.075" out from bolt face.

Of course excess headspace could be a cause or any of a number of reloading issues already mentioned by others.

A tricky one to measure is the pin/striker length of engagement at full cock. This is one probably best checked by a smith who knows what they are doing with a Win 70/Mauser type bolt. And in any case, if uncomfortable with any of these DIYs, let a good gunsmith look at it. Hope you can get to the real cause.

 

[Hogpatrol]

Just for reference, there's not that much difference in primer heights between the 250s and the Rem.

 

[Wyatt Smith]

Thanks for the help guys, I cleaned the bolt and will look for rubbed or glades spots on the pin. I will also check the pocket depth and primer thickness.

 

[bruce moulds]

always seat primers firmly to the bottom of the primer pocket.
this way the anvil is fully supported when the pin strikes.
if that happens, headspace is supporting the case properly, and firing pin protrusion is just over 0.060", there is something else wrong.
bruce.

 

[Hogpatrol]

If you have a suitable place where you can shoot a few primer only rounds, no powder or bullet, and compare strike indentations, it may give you another clue as to the problem.

 

[sestoppelman]

Results of that will be inconclusive at best because primers alone wont expand the case and the brass often wont even hold the primer tight and it will back out, sometimes tying up the gun. You wont really learn a thing.

 

[Wyatt Smith]

I did some measuring, my firing pin protrudes .056 trough the bolt face. the height of my primers has a high and low of .128 and.133, most being .132 (remington). the primer pocket depth of my brass (all brands) has a high and low of .130 and.127.
These numbers seem to add up to being OK to me. I've got high hopes for my extra power firing pin spring solving my problem, and not a head space issue. Also the fired primers are not flattened much, and it appears to be the same as my other rifles loads are.
Thanks for the help guys!

 

[Shawn.54]

I had a revolver that gave me same problem I fixed it by buying my dad a Lee primer tool.
Any brand will work. He was using primer seater on his Lyman press and do to high mechanical advantage did not have a good feel for primer seating he was short seating primers. When they are short seated they will seat the rest of the way with the pin strike but this action will also will deaden the strike. Clean pockets also help.
Shawn

 

[Wyatt Smith]

I had a revolver that gave me same problem I fixed it by buying my dad a Lee primer tool.
Any brand will work. He was using primer seater on his Lyman press and do to high mechanical advantage did not have a good feel for primer seating he was short seating primers. When they are short seated they will seat the rest of the way with the pin strike but this action will also will deaden the strike. Clean pockets also help.
Shawn

I suspected that and actually ordered a Lyman hand primer about 20 minutes ago.

 

[Shawn.54]

My revolver was 1 of 3 in my family All the same make and model mine was not alone with the misfires but I was getting one or two misfires per cylinder compared to 1 every 150-200 shots for the other two. Factory ammo was flawless I inspected the ammo and found dad was not getting primers seated. I have not had a misfire since I got the hand primer tool. I believe this will cure your problem as well. I do make a point to look and feel each primed case at least twice before charging or seat bullets.
Shawn

 

[perttime]

I suspected that and actually ordered a Lyman hand primer about 20 minutes ago.

Can you manage to do a little test firing with only one "fix" in place?

 

[bruce moulds]

look for protrusion more like 0.063".
bruce.

 

[Wyatt Smith]

Can you manage to do a little test firing with only one "fix" in place?

Yes, I have the same lot of ammo that failed to fire several times. I will then try the new spring with that ammo, should that fail I will try the new primer tool and so on

 

[Wyatt Smith]

look for protrusion more like 0.063".
bruce.

Do you think my pin is too short, Or is it something else?