This a Primer or Trigger issue?

[hk dave]

Trying to figure out if my FTFs are a primer issue, or perhaps something wrong with the trigger.


I've attached some photos here... the taller shells are still loaded rounds that didn't go off. With these I reset the trigger and fired 2-3 times, waiting 30 seconds between firings.


The shorter are empty brass cases that fired.

 

[varmint slayer]

Is this a new or new to you rifle?

 

[hk dave]

Yes, brand new rifle, built by a VERY reputable company. At first I thought maybe it was the Rem 700 Timney trigger causing problems, so sent it to Timney and they kindly changed out the parts to work with the Surgeon 591/R. Problem persists though.

 

[cmh2007]

hand loads?

 

[hk dave]

Reloads from a very reputable ammo company.

When the ammo does fire, it's printing sub 1/2 moa groups.

Hmm I think maybe I should try it out of another rifle to see if I have the same problems.

I'm doubting it's the rifle because to me those primer strikes look pretty heavy.

 

[roggom]

Dave,

I recently picked up some once fired ppu match brass and also noticed two things:
(1) I had the same FTF on some cartridges. I would safely wait a good 20 count then recycle the bolt and most would fire again. Some didnt

(2) I have to cam the bolt up at the very top of the cycle. It is not a sticky bolt issue, just seem like the extractor was binding or something. It wasnt pressure because I was using a lighter load. The bolt could be lifted with one or two fingers, and there was a "click" at the top

I measured the thickness of the case head and it is thicker than both the RP and Lapua that I shoot. Also measured primer pocket depth.

Rim thickness / PP depth

RP .047 / .139
Lapua .050 / .129
PPU .051 / .136

These were just three random cases, but I can only speculate that the combination of thick rim and deeper PP is causing the FTF. I just put all the PPU in my SHTF box and moved on. It was a bummer because the ones that did fire were pretty decent.

BTW the FTF were in both of my R700, they have never had FTF with WW, RP, Lapua in the past.

 

[varmint slayer]

Yeah if you have more of the same ammo and access to another rifle then I would try that for sure. My buddy had a Tika .270 WSM that did this same this. Firing pin depth checked out, trigger, ammo in another rifle checked out, ended up being a headspace issue.

I like roggom's info as well. Something to look into as well

 

[hk dave]

Thanks guys for all the great info. I'm gonna try it out of my OBR next time I get to go out. Hopefully there'll be no issues and I can just use all the PPU brass for that particular rifle.

 

[ajwcotton]

I would check your firing pin protrusion. Pull your bolt and let the pin drop and measure the protrusion. If that checks out you might try a slightly heavier firing pin spring I had to put one in a defiance action to get reliable ignition.

 

[DarnYankeeUSMC]

Do you have an OAL head space gauge? Check the FTF ones against a fair amount of some you have not tried to fire. Check to see if they were overly sized. they may be moving in you chamber when the firing pin strikes causing the FTF.

 

[Deadshot2]

Do you have an OAL head space gauge? Check the FTF ones against a fair amount of some you have not tried to fire. Check to see if they were overly sized. they may be moving in you chamber when the firing pin strikes causing the FTF.

Anther vote here for checking headspace measurement on the unfired cases. I had the same problem with a whole batch of brass that was F/L sized and was waaaaay short. Compared to fired cases they were as much as .015" shorter when measured with a Hornady Headspace gauge. Also dropped too far into a Wilson Case gauge.

FWIW, did the primers protrude from the case on those that did fire? Put the straight edge of your caliper across the case head and see if the primer keeps it from touching the brass. On light loads this is very pronounced when you have a case that's been sized too short.

Also noted in the pic's that this brass has had the primer pockets reamed rather than swaged. Some look like they have a pretty large countersink/chamfer. It's possible that the "tool" also cut the primer pocket too deep.

 

[hk dave]

Ok, ordered a Wilson Case Gauge and an RCBS Precision Mic. Hopefully this creates a solution for this. Am also going to try this ammo out of my OBR and see if I have the same issues. Too bad my other 308 bolt gun is being worked on, would love to have tried it with that.

 

[milo 2.0]

Did you pull any bullets to make sure the primer didn't go off?

 

[insight3b]

Looks like the primers were bad to me

 

[BuzzBoss915]

Why did you fire so many? Obviously, something is wrong. It does not look like the firing pin is the problem, it makes a decent dent in the primer and half of them did fire. How did you ever come up with a trigger problem? You might as well have blamed the scope, as the trigger.

I would check the primers, just to be certain there is no contamination. Maybe you can squeeze them, (a few) in a vice, or hit them with a hammer if the anvil isn't too damaged. That would be just for curiosity, but half did fire, so you didn't get a bad box of primers. And, BTW, if you do it, wear goggles. Primers are usually tame but they are still explosive so be careful.

All this is a matter of covering all the bases, but DarnYankeeUSMC has the best idea, as far as I am concerned, especially since you said that this is a brand new rifle.

I think you have headspace problems and your reputable builder needs to get involved. Reloading the one's that fired and are now fireformed probably will not fail to fire, but you need to stop and get the gunsmith involved. BB

 

[MAGUA]

Looks like the primers were bad to me

I agree those primers should have ignited . I would also pull the heads like Milo said to see if there is any powder in the case.

 

[hk dave]

Reason I didn't originally think it was the ammo was because I ran the same ammo through my OBR and it ran perfectly. (I later looked at the headstamps and came to realize that the ammo that ran perfectly, while the same load, used FC brass so the brass could have been bumped differently)

I came to the conclusion that it could be the trigger because I had originally bought a standard Timney 510 to drop into my Surgeon. About a third of that box of ammo was shot using that trigger. Spoke to Timney, they said I needed a different sear so the trigger went back to Timney to have the sear changed out.

While it helped a bit and I noticed some rounds still FTF, didn't cure the problem.

Hoping to mic the headspace to see where this ammo is at once I receive the rcbs precision mic and wilson case gauge. I'm leaning toward the bump on the PPU brass being an issue since all the FC brass actually shot fine with the same primers.

Also hoping to take the rifle to the range and try different factory loads out of it to see if I still have the same problem.

If the PPU cased reloads run fine out of my OBR and my other bolt gun (that i'm hoping will be done soon), I'll start looking into the rifle being the problem... although I find that one kind of hard to believe... but I suppose everyone makes mistakes.

Scientific method... guess I did learn something in school... all those years ago.

Just having this conversation with you fine and knowledgable folks is helping a lot. Thank you!

 

[sinister]

I have to agree with the gent above that you should check firing pin protrusion and firing pin length, and possibly the weight/length of your firing pin spring -- your pin indents look shallow from your photo angle -- coupled with hard or less sensitive primers and you won't get the spark you want.

 

[SPAK]

You can get a quick idea on you headspace buy measuring the fired cases and then comparing it to new unfired cases...it won't be perfect, But if it's really too long it might give you an idea of where your chamber is at.

My very first custom build had a headspace that was .020" too long just based off of new brass to once fired. In the end I think it was actually longer than that... Don't take it for granted that it was built correctly..

 

[Edo1]

Call the company that reloaded the ammo and see what they say. I've seen reloaded ammo from a reputable company have problems in the past. The ammo is the most likely source of your problem. Also, shoot some ammo from a different source in that gun and see if you have problems. If those reloads work in another gun, it can still be an ammo problem. What did the primer strike look like the first time it wouldn't fire, before you tried a second time? PPU brass isn't know to be quality stuff.

 

[milo 2.0]

Again, I think you need to pull 4-5 bullets and check for powder, if it's there, does it look good? If you don't have a press and a die, get it to somewhere to decap the primer and see if it went off. If it didn't go off it's either the primer or a headspace issue. To me, the firing pin strike looks more than adequate.
You say it's reloaded ammo, was the brass yours to start with? You say it's a new gun, so the brass wasn't fired in this gun to start with?

I see alot of issues buying reloaded, or remanufactured ammo, if it's not your brass, where did it come from? How many times has it ben fired? Is it some overworked crap, or once fired?
Here in the for sale section, all I see is once fired brass, all of it. I'm non military, and the local PD or Sheriff's department hasn't invited me out for an afternoon of blasting, so I've never been to a factory ammo only range, so range pickup brass for sale, triggers a red flag. A guy selling once fired brass who doesn't reload, it's factory ammo that's shot and the guy is dumping it to buy more loaded ammo, fine. Do you think someone who reloads is going to buy factory new brass, shoot it once and dump it? I suppose if he's switching guns, OK. If not he's either rich, or stupid, or both.

Even if you sent your brass in to be reloaded, does one think they're going to measure it and set the die accordingly, or have the dies set to saami specs?
I'm going to shut my rant down, but I think you can see where I'm taking this. I do realize every person's financial situation is different, but I'd really look for different options.
If I'm going to shoot other's loaded ammo out of an out of spec chamber, I'd want it to say Remington, or Winchester or the like on the box, just in case.

Last year I had Chad Dixon chamber 2 6.5x47's for me, same reamer, 4 month's apart. I watched him build both guns. One gun I can get by with neck sizing only, one needs fl sizing. I watched him use his tricks to ensure headspace was correct on both guns, so what gives? Both guns shoot lights out, virtually the same.
I can gaurantee Remington, or Savage, or the like companies don't have near the quality control that comes out of his shop.

 

[Edo1]

The problem with the primers that didn't fire is that they were each struck 2 or 3 times according to the OP. There is no way to say if the firing pin strike is adequate or not. The picture shows a cumulative result of 2 or 3 tries. Also if the strikes did look adequate on the first try, how could it be a head space issue? Seems like you guys are saying if it was a head space issue the primer strikes would be weak.

I also think that if the primers fired, even if they didn't ignite the powder, there would be enough force there to push the bullet into the barrel. Depending on the powder that was used to reload these, just shake the bullet and you should be able to hear if they have powder in the cases, unless the case is completely full. There is no doubt that those unfired rounds have primers in them that didn't light.

I think that with today's issues involving the lack of reloading components, that companies are going to be stuck using whatever components they can get. This may mean that some will have to use poorer quality components than they have used in the past. The result will be shooters having more problems with their ammo.

 

[sigma2chi]

There is a noticable difference in the primers at the bottome that did fire. Some are cratered some are not even close to being cratered. I've never see that much of a variation visually, in expent primers fired from the same gun. Those loads don't look consistent to me just from that. Looks like an ammo issue for sure. Definitely update when you narrow it down though. Interesting problem...

 

[DarnYankeeUSMC]

After you get a head space gauge measure the ones that did fire and compare to the FTF. The cases that fired will match your chamber. This will tell you how loose the FTF are in your chamber.