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Help with firingpin

I've just got thru with my 6.5-06AI build. I built the whole with the the supervision and guidance of my gunsmith. Here's the problem. I loaded up 30 rounds to fireform brass. W-W 25-06 brass, 51gr. RL22 and started out with CCI LR primers pushing 144 grain FMJ of sometype. Out of the 30, 10 rounds didn't fire. Primer never ignited. I took 6 of the misfired rounds and then used the same powder, case, etc as the misfired round and put Rem. primers in them. I shot them today 2 out of 6 didn't go off. Here are some pics of the primers. 2 on left are rem. 2 on right are CCI The middle to are fired and outside 2 are misfires.
IMG_6999.jpg

I changed out the firing pin and firing pin spring during this build. I installed a Speedlock. I noticed when I took the original remington spring out the spring was alot more coiled and bunched up. My other Rem 700 is at the smiths to so I don't have a referrence for this but my cocking peice doesn't seem to be sticking out very far pass my bolt shroud when the gun is cocked. Atleast that's compare to my model 70..Does this look right??
IMG_7002.jpg

Here is some pics of the firing pin. Notice in 2nd pic how little spring coil there is and this is with the cocking peice pulled back alot futher than it's suppose to be for opperations. I'm wondering if it's a SA spring.
IMG_7003.jpg
IMG_7004.jpg
 
I would look very close at the headspace length of the loaded rounds, as ready to fire form to the AI chamber, especially the shoulder angle. Were the shoulders pushed back excessively, so the loaded round is sitting in the chamber, bolt closed, but with a lot of slop front to rear? If they are, then the firing pin hits the primer, and drives/pushes the round forward in the chamber, cushioning/softening the "hit" made by the firing pin. I must admit to not having any "hands-on" knowledge of the Ackley chamberings, but going from the shallow 17 1/2 degree angle of the 25-06 with body taper, to the 40 degree angle without as much taper, could be the problem. It could be nothing more than the FL sizing die being adjusted too far "down", and over-sizing the case.
 
Summitsitter,

I would more suspect the absence of shoulder contact when fireforming than a FP problem, as it seem indenting right on normally fired cases.

The smaller indentation are example of case being held only by the extractor. This cushions the impact.

Your chamber is either too long, or your brass sized too small for the chamber.

Two solutions:

a) Use brass of larger calibre, say 30-06 and neck-resize them to your caliber/chamber lenght in order to create a small shoulder who will bear the round against a small amount of the chamber shoulder when fire-forming.....and made the fire-forming better also.

b) Continue your fire-forming as you do it until you have a sufficient number of fire-formed cases for serious shooting!!.. But then consider also you can run into exractor problems, as usually, they do not like this treatment!!.

R.G.C
 
R.G.C.: We were both posting at the same time, and both came up with the same "cause"--- interesting that neither of us thinks it is a firing pin problem: I'm leaning toward "brass sized too small for the chamber".
 
I also think it is not a firing pin problem, It may not be a resize problem either, Whenever I'm fireforming I try to make sure the bullet is jammed into the rifling. This keeps the round firmly seated against the bolt when chambered. This simple solution should solve your problem.
 
oneflyer: Excellent advice. On very rare occassions I've had a mis-fire when fire-forming Lapua 220 Russian to 6ppc, had the feeling it was caused by a sloppy fit, front to rear, and can see how seating the bullet "long" for a jam fit would help. I will, in fact be fire-forming a new batch of 220 Russian for a new 6ppc chambering, and will make it a point to seat 'em long. Been at this "game" since 1960, and still learning. Thanks. ;)
 
fdshuster said:
R.G.C.: We were both posting at the same time, and both came up with the same "cause"--- interesting that neither of us thinks it is a firing pin problem: I'm leaning toward "brass sized too small for the chamber".


fdshuster,
I had just the same reaction when I read your post.
The important in FF is to keep the case head firmly against the bolt face recess. One method has been explained in an other post, not being the best, as impact can be strong enough to still allow the case to move forward on impact.
If the case is allowed to do so , the neck hold in the chamber on firing, and the metal is even more worked than if the FF was made normally, this is to say allowing the metal to flow forward without starting the case body stretching.


About 'brass sized too small for the chamber" sorry, my english is not what I would like it to be...be indulgnet....

R.C.C
 
Are you starting with new brass? If so, can you feel resistance when closing to bolt on an unfired round? If not..the chamber is too long. There should be a slight crush fit at the neck shoulder junction.This is what should keep the case from moving forward when FF to an AI, and is what I suspect to be your trouble.--Mike Ezell
 
I agree that it sounds like a headspace problem. Try loading some with the bullet pushed tight into the rifling and see if that cures it.
 
Thanks guys I'll do somemore investigating into the headspace issue. Only thing that makes me think it may not be headspace is that the same round may fire the next time with a new prime. I'll do some serious checking on it today.
 
Okay messed with it some tonight.
1. New virgin, untouched, straight out the bag 25-06 brass doesn't seem to have the "crush" fit. If there is some there it's not much at all
2. Loaded some rounds back up with bullet jammed into the lands.( good advice)
3. If I can fight my way thru this will it really matter after I get all the brass fireformed. Will the headspace be correct then, or will I still be having this problem.
4. Headspace can't be to long. I had a round that wouldn't chamber the other day. I jsut stuck it back in the box and carried on. Took it out tonight and noticed that the primer wasn't totally seated. Therefor the round was to long and bolt wouldn't close. When I say not seated I don't mean buy much.
 
Primer(s) not fully seated can also cause mis-fires, since, just like a case that is lose in the chamber (slop front to rear), the firing pin will hit the primer and push it deeper into the primer pocket, so the primer is not getting the full force of the hit. I seat my primers 'til I can feel them bottom out in the primer pocket, and with the tip of a finger can feel them a few thousandths below flush. To further check for proper seating I will stand the primed case upright on a small piece of flat steel, and I don't want to see the case "wiggle". Another good reason to keep the primer pockets clean without the debris that builds up, although I understand you are working with new brass, so that's not the problem. Have never used the press mounted priming attachment(s), like trying to drive a tack with a sledge hammer.
 
If your virgin brass doesn't have even a slight crush fit,you will need to seat the bullets to jam into the lands.You could take a few unprimed cases ,chamber then ,insert a cleaning rod in the muzzle with a 270 cleaning brush or whatever you have for a snug fit in the case mouth,and posibly feel the movement in and out.with a plunger type ejector,you could get a false reading.If you don't want to seat all bullets into the lands,you could sort the cases with a bump gage,and set aside the short ones for the bullet jam seating.
http://www.sinclairintl.com/product/5574/Case-Gauges-Headspace-Tools
 
When fire forming ackleys Improved cartridges as this one is . It is important you know how much crush there is do not suppose it is right or it feels good . You have to measure it and measure accurately fighting your way through it is a good way of getting a bolt through the back of your head. You must have contact on the shoulder to keep the head in contact with the bolt face . Not all new cases are the same lenght very important to know .I have built many of these and I shoot them in competition and have yet to blow one up or split brass. See the PM I sent you . mike
 
For firing forming i use a false shoulder to keep the case head up against the bolt head. This can be done with a expander thats one size over your caliber then start you neck die high and go down untill the round chambers tightly. Have you check to see if the cocking piece is dragging on the side of the trigger group or anywhere on the back of the action and bolt? Did you put it together dry of use a lubricant of some type? It looks like your protrusion is just fine but something is stopping it from hitting full force once in a while.
 
blawton said:
For firing forming i use a false shoulder to keep the case head up against the bolt head. This can be done with a expander thats one size over your caliber then start you neck die high and go down untill the round chambers tightly. Have you check to see if the cocking piece is dragging on the side of the trigger group or anywhere on the back of the action and bolt? Did you put it together dry of use a lubricant of some type? It looks like your protrusion is just fine but something is stopping it from hitting full force once in a while.

blawton,

As, to achieve this, the neck opening would need to be at least to .30, in order to save working of the case, why not then start directly with a 30-06 new brass?

Recently, a friend broke an extractor while fire-forming.260 INCH cases from .260 Rem ones. I recommended strating from .308 brass, using an old .308 barrel with the shoulder cut with the .260 INCH reamer to shoulder and depth of the .260 Inch. Shooting .308 light loads with heavy bullets seated long, the shoulder formed beautifully, and all what remained to do was to size the neck to the .260 dimension.
FWIW

On the question of protrusion, it was mentionned seating variations, and this, combined with the absence of hold by the shoulder, certainly explain that..
R.G.C
 
did the bolt close easy on the go gauge ? was it a standerd 30-06 guage ?

if you go to dave masson reamer they have good info on how to set ackly head space,

but in short you should not beable to close bolt on the go gauge as if it was the no-go
 
p17enfeild said:
did the bolt close easy on the go gauge ? was it a standerd 30-06 guage ?

if you go to dave masson reamer they have good info on how to set ackly head space,

but in short you should not beable to close bolt on the go gauge as if it was the no-go

P17,

Not sure to read correctly the last sentence..It goes against all what I have always learned about gauging..

Are you also sure 30-06 standard gauges are useable for 30-06 AI?....

R.G.C
 
Plus 1 for the false shoulder method, it's really the only way to go.. Unless you have a ton of neck tension you'll just end up pushing the bullet into the case when using the long seated bullet method... this will also cushion the firing pin blow resulting in a FTF..
 

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