Ignition

T

Tom R

Guest
HI,
I have a question for the experts.
From what I have read some actions have better ignition than others.
Well after looking at fired shells and targets.
How do I know if that is a problem?
What should I be looking fore?
How do I correct it?
Thanks
Tom R
 
WELL,
JUST as I expected.
Read something and support rumors
WITH NO FACTUAL BASIS

Tom R:mad:
 
What Action?

Tom:
Give us more information as to what you are looking for. Good ignition can be found in many very good actions, you need to first off, make sure you action, bolt assembly and trigger are as clean as you can get them. Never ever oil a trigger and keep oil and grease out of the FP assembly. They will only gather dust and fouling, and slow down the working of the complete unit. Check the tip of the FP, and make sure it is not chipped or broken off. There have been several good articles written about Ignition, but you can't always trust the writer to be able to give you remedies. Size a shape of the FP tip pay are a huge part of the equation, as well as the weight of the FP spring. Too light you have a problem, and too heavy you create additional problems. Of course, CF and RF are different, so be patient and wait for some others to step up and provide some additional helpful information.
 
Fred,

I think the real question is how would one tell if there was an ignition problem. I've looked at indentations of the rim and I know how that should look, but other than that, I guess I would just let a gunsmith tell me if the ignition was good or not. He has a good question and I'm sure somebody on here can answer it.
 
Too Good

Beau:
Often, when one increases the spring rate to improve ignition, they go too far and cause additional problems. My 52D was shooting great, and on the advice of a well known gunsmith, I change the FP spring with a newer HD spring. The gun went to pot. I could now see the cross hairs vibrate when I would dry fire, ( with a snap cap )when with the old orginal factory spring, the was no vibration. I went from what was so-so ignition and great performance, to great ignition with poor results. Go figure.
 
Simple Question?

Forgive my naivety, but the issue of ignition raises a question that I haven't found an answer for. From all that I have read, it seems that most people would agree that good, solid ignition is one of the many keys to accuracy. It seems to me that striking a cartridge in a single spot eccentrically with sufficient force to dent the rim on one side could potentially cause a problem with accuracy. Also, from an uneducated, simplistic view, it would seem that starting the powder burning from one corner in the bottom of a cylindrical cartridge could cause an uneven burn. Why don't we use 2 firing pins that strike the rim simultaneously and symmetrically on opposing sides?

I realize that smarter people than me have looked at a rimfire cartridge and though about this before, and surely there must be a good reason why we don't do this?

Dean
 
Dean,

The original Flobert bulletted cap (grandaddy of the rimfire cartridges) used a chisel ridge across the full width of the hammer which also served the purpose of containing the explosion. Back a decade or four, the French manufacturer, Gevarm, had a semiautromatic that fired from the open breech that had a similar ignition arrangement.

I seem to recall that there was a continental manufacturer who toyed with a "Y" ended firing pin to modify ingnition in the way you're suggesting, but the bottom line is that about any manufacturer can produce at moderate cost a single impact, suitably shaped or pointed firing pin timed to strike consistently at a single point is suitable for most purposes, except perhaps the benchrest shooter who wants an advantage over his fellows & maybe there isn't enough of them to ante up the cost.

Have you read this article by Bill Calfee? http://billcalfee.org/articles/articles.html

John
 
2 firing pins

I had a Savage, NRA Model 19 I believe. It had 2 firing pins. I think it was to insure the rifle went bang rather than for uniform flame into the powder.
 
Dr Dean
The Time Precision action has two firing pins. One of the reasons I bought the Times back in the mid 90's. Many folks are removing one. I think they have tested and found it shoots better because a lighter spring can be used causing less vibration. I have two Time Precisions. I have found the opposite. I bought and extra firing pin and modified it for single pin hit. Also modified a spring for a lighter hit with only one pin. I found testing four lots of Midas a few years ago that I get lower Standard deviation with the dual pins on all four lots in both guns. Slightly higher velocity. But both guns shot better with two lots and about the same with two using the dual pins. Not the same two lots.
The Time has some other problems that the action can be very stiff to operate with the stronger spring required to drive dual pins. I have one gun set up with the single pin so my 10 year old granddaughter can shoot it.
Rich
 
Tom R,

Earlier this year my Turbo was shooting awesome. That gun would agg. nearly 2300 (ARA) over 6 targets in ideal conditions. Then all of a sudden, I could not shoot over a 2100. It did not shoot horrible, but all of my scores were 2000 to 2100 no matter what the conditions were. I checked everything I could think of and it turned out to be the firing pin. The firing pin tip had "mushroomed". It did not have the hard crisp edges that it once had. Looking at my fired brass, you could not tell any difference. That gun drove me crazy for about a month. It made me a believer about ignition being critical. We have since replaced the firing pin. Now the gun is back to about 90% of were it was. We are still tinkering with it. It seems now the firing pin hits a little too hard. I can feel, hear, and see the vibrations that Fred J was talking about. The gun is much better than with the bad firing pin, but not as good as it originally was.

"How do you tell if you have bad ignition?" Look at firing pin to make sure it is shaped properly and not "mushroomed", look at fired brass to make sure the pin strike is hitting hard and it is hitting the rim. You want it to hit the rim, this is where the primer is located. Also, how is the gun shooting. When mine had poor ignition, I would get an unexplained 25. Then the next 3-4 shots would take the dot out, then another 25. The final proof for me on poor ignition with my Turbo, I used a bolt from another Turbo that was smithed by Myers just like my Turbo. When I used the different bolt, the gun was back to her old self and shooting great.
 
Last year my anschutz had the trigger slip forward loosing ignition. you would get several xes then a -2 straight down. I moved the trigger back and the gun was ok but not quite there. I put in heavier springs and the gun shot well but I found it would not shoot in a left wind. Lightening the spring helped but in the end I also had to retune the rifle. There is a very fine balance in a presision rifle, you can have too much or too little ignition.
Steve
 
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