Soft primer .22LR Ammo?

[BigBoy1]

Does anyone know of a brand of .22LR ammo which is noted for having a "soft primer"? I think it is the idiosyncrasy of my rifle but it takes two strikes of the hammer it ignite the cartridge. The first strike puts a small dent in the rim and the second hammer strike will fire it. (I have the cover off of the rifle so the hammer is exposed for manual-recocking.) In the picture below, the first strike is at the 12 o’clock position. The round was repositioned in the chamber and tired again. At the 4 o’clock position are the two strikes which ignited the cartridge.

http://i163.photobucket.com/albums/t308/i422twains/PICT0310.jpg

Once in a while the first strike will ignite the round but this is very rarely. The same ammo works just fine in my other rifles. The two types of ammo I had the last time I went to the range were Winchester and Agulia. The problem occurred with both types. If I can avoid going to the store and buying a box of every different .22 ammo and trying them, I would appreciate any help for any known soft primer starters for the ammo purchase. Thanks.

[JCHannum]

What is the make of your rifle? it appears that the firing pin strikes the primer in different locations as well as with different force.

It could be as simple a matter as dismantling and giving the internals a good cleaning. 22's will generate a good deal of gunk that will slow the firing mechanism to the point that it will not function properly.

Another place to look is at the chamber mouth. Dry firing can damage the chamber mouth, either removing material behind the rim or upsetting material that will impede the firing pin.

[biometrics]

Check for burrs on the firing pin itself or even the channel that the pin rides in that may intermittantly catch and slow the firing pin fall (sometimes). Polish these areas and lubricate and then see if you have the same problem.

Another possibility might be that the spring that the firing pin uses to strike may be too weak...

[Bob D.]

The single strike mark on the cases seems too shallow to me. Perhaps something in the firing pin's path is impeding its forward motion. I would suggest disassembly and a thorough cleaning. I like Birchwood Casey Gun Scrubber for jobs like this.

.22's can get pretty grimy!:D

I've experienced more failures to fire with Agulia than any other ammo in my 10/22. A second strike almost always sets it off, but it's a PITA!:p

What firearm are you using?

[kf2qd]

Check the hammer spring, hammer pivot, firing pin and its guide for dirt, rust, general crud and clean and oil well and see if that doesn't help.

I have has misfires on old rounds, but never on fresh stuff.

[Cobbler]

From what you have stated, this is absolutely not an ammo problem but a gun problem.

What is the make and model of the gun?

Photos of the gun would be helpful also.

[BigBoy1]

Check for burrs on the firing pin itself or even the channel that the pin rides in that may intermittantly catch and slow the firing pin fall (sometimes). Polish these areas and lubricate and then see if you have the same problem.

Another possibility might be that the spring that the firing pin uses to strike may be too weak...

The firing pin and channel are perfectly clean and there are no burrs any where. This was checked before I went to the range.

I'll post a series of picture of the firng pin and bolt.

[Bguns]

Looks like fp is hitting too far toward center of cartridge. Needs to hit the very edge of rim...

The priming compound is not getting sqeezed enough toward center of case, it is unsupported there. It has to hit solidly in the rim area so the compound can go off.

If the firing pin tip is reshaped into more of a dull chisel shape,( Edit: have not seem many modern RIFLES with a rotatable firing pin :) ) it will concentrate the FP energy into a smaller area. Be sure to watch FP protrusion, so it does not damage chamber edge.

Old Red box Federal used to work well in sensitive .22's... But the modern bulk pack requires a good solid FP strike.

[38_Cal]

The "dull chisel" shape is fine for a pin that's either flat or is otherwise unable to rotate in the bolt, but will not work for many action designs where it can rotate. Protrusion should be about .038" (unless the pin is also the ejector), and the tip shape, if the pin is free to rotate, should be a somewhat flattened hemisphere.

David

[Toolguy]

To the OP - CCI Mini Mags are the softest ones I know of.

[madokie]

winchester super X has always worked well for me over the years,remington and federal ar'nt well thought of right now, try Wolf match.carefully check and clean chamber first,bolt face too,and extractor.chamber and gun could be wore out from too many rounds also,or chamber machined off center.check gun carefully make sure bolt can go all the way forward,and extractor isnt holding round back either.good luck.

[BigBoy1]

winchester super X has always worked well for me over the years,remington and federal ar'nt well thought of right now, try Wolf match.carefully check and clean chamber first,bolt face too,and extractor.chamber and gun could be wore out from too many rounds also,or chamber machined off center.check gun carefully make sure bolt can go all the way forward,and extractor isnt holding round back either.good luck.

All of your suggestions were done but problem still exists.

[BigBoy1]

After reading comments and talking to other people, I'm going to make a new firing pin with a different shaped head. The round head firing pin is what in on the tip righ now and I'm thinking a chisel point tip for the new one.

The reason is, if one looks at the amount of force applied to the rim of the case, the round pin has a large area. Remembering that pressure equals force per area. The force of the blow by the hammer is going to be constant so the pressure applied to the rim of the case will increase as the area of the firing pin decreases. The round tip has a large area where the chisel point firing pin will have a small area, thereby increasing the pressure applied to the case.

[Cobbler]

Critical piece of information missing......!!!!!..... What is the make and model of the gun?

[BigBoy1]

I have a military .22LR sub-caliber conversion kit for the FN FAL rifle. This conversion kit was used for troop training and was made by Erma-Werke for the Germany Army when they were using the FAL battle rifle as their standard service weapon. Here are pictures with explanations.


http://i163.photobucket.com/albums/t308/i422twains/KitinFal.jpg


http://i163.photobucket.com/albums/t308/i422twains/KitinFal2.jpg


http://i163.photobucket.com/albums/t308/i422twains/BarrelandMagazine.jpg


http://i163.photobucket.com/albums/t308/i422twains/Barrel.jpg

[BigBoy1]

http://i163.photobucket.com/albums/t308/i422twains/BoltandSpring.jpg


http://i163.photobucket.com/albums/t308/i422twains/BoltEnd.jpg


http://i163.photobucket.com/albums/t308/i422twains/BoltFront.jpg


http://i163.photobucket.com/albums/t308/i422twains/BoltBottom.jpg

[BigBoy1]

http://i163.photobucket.com/albums/t308/i422twains/BoltDisassembled.jpg


http://i163.photobucket.com/albums/t308/i422twains/FiringPinNoGap.jpg


http://i163.photobucket.com/albums/t308/i422twains/FiringPinGap.jpg

[Cobbler]

Thanks for the photos and explainations. That really helps.

I must admit that I have never seen this particular conversion in person but they have a reputation (Erma Werke in general) that proceeds them and is not good. Many of the guns they made in 22 to resemble other famous guns were considered "parts guns" while still new-in-the-box.

I did a bit of research on this particual piece and it seems that Erma's products are nothing if not consistant. Reviews state that one should consider themselves lucky if they get it to work at all as up to 90% do not without considerable work (don't know what this work is though). Another negative review from some was the thin liner developing bulges which then prevented removal of the insert barrel, however some folks suggested that an unclean 7.62 barrel bore may be another likely culprit on difficult insert removal. It was also noted that they are a bit rare (I think this is due to Erma not being able to get them to be reliable and dropping the product soon after introduction) and that there may be some collector's value to this model.

Looking at the photos, there are some things that seem very counter intuitive to reliable design. The first thing is the two-piece bolt with the firing pin running through both. Getting something to slide consistantly and easily through 2 parts just does not bode well for reliablilty. Considering the firing pin fit is likely somewhat close tolerance whereas the bolt raceways are purposely of higher tolerance (for reliability of the original gun as designed), it is a wonder it can be moved at all. The other really big design problem is the spring on the firing pin. Typically, guns which use a hammer and separate firing pin either have no spring or have a weak spring which holds the firing pin rearward. This one has a spring which appears to have a little bit of strength to it based on its length holding the firing pin forward. The typical setup has the hammer striking the firing pin which, in turn makes the jump from rest position to the cartridge gaining speed along the way. This setup has the firing pin resting against the cartridge so basically it is a simple transfer of the hammer's power minus drag (which may be considerable with the two-piece bolt and all its binding potential) and minus the power and dampering ability of the firing pin spring.

Another thing that I can't figure out from the photos is why the firing pin has the flat spot along its length. I am not seeing any sort of retaining pin or screw which would ride there.

There..... that wasn't much help

[BigBoy1]

Another thing that I can't figure out from the photos is why the firing pin has the flat spot along its length. I am not seeing any sort of retaining pin or screw which would ride there.

If you look at the picture of the rear of the bolt, you can see that the bottom of the firing pin is flat. The hole in the rear of the bolt is not a round hole but an opening which is semi-circular at the top with a flat bottom. This will prevent the firing pin from rotating. This is the main reason I'm considering making the hemispherical firing pin tip into a chisel point. This flat side on the pin will keep the chisel point aligned in the correct position for striking the case rim.

Where did you find your information on the Erma products? I'd be interested in reading it myself. Thanks.

[JCHannum]

That is quite an assemblege of parts. In line with Cobbler's assessment, the two part bolt, long firing pin and rather strong firing pin spring do not contribute to a smoothly functioning operation.

It appears that the firing pin is in contact with the cartridge rim and held back by the rim when a cartridge is chambered. This is a kind of scary situation, and a chisel pointed firing pin might make it more dangerous if over done. Make sure there is a generous radius on all surfaces if going this route.

Before taking that approach, I would try stoning and polishing all areas of contact of the firing pin and bolt internals, paying particular attention to the enlarged section of the pin and the areas of the two sections of the bolt where they all come together. This is the area where interference is most likely to occur.

[Cobbler]

Here's a couple threads from the FAL Files which cover most of what I have been able to find.

http://www.falfiles.com/groups/showthread.php?threadid=297224

http://www.falfiles.com/forums/showthread.php?threadid=294015&highlight=erma

It seems Erma made the conversion (above) which did not work so they contracted to H&K for a redesign which was too expensive so they went out of production alltogether.

Just for fun, and at a secure range, AND with only 2 or 3 rounds in the magazine, try to fire it without the firing pin spring installed. I have a feeling that with the spring holding the firing pin forward that the rim is being crushed just by the operation of feeding a round and that when the hammer hits the pin, the rim is already crushed and rendered less sensitive in that one spot. The way it is now, the bolt face is akin to a fixed firing pin as seen on many open bolt submachine guns. Removing the spring would convert this to something similar to the early imported SKS rifles without firing pin springs (to RETRACT the firing pin) which were sometimes able to empty a mag due to the inertia of the firing pin striking the primer as the bolt closed. If complete removal of the spring does not result in a runaway and also makes single ignition reliable, you may then move forward on either eliminating the spring or modifying the spring to barely any power.

Without a RETRACTING spring on the firing pin, I would be very hesitant to add the "chisel" feature to the firing pin or sharpen it in any manner.

[Cobbler]

Thinking about this a bit more...

Regarding my suggestion of trying it without the firing pin spring, I think just removing the spring would allow the firing pin to travel rearward so far that it may cause other problems, namely the two halves of the bolt no longer being joined by the firing pin and also, the firing pin resting so far back that the hammer hits the bottom of the pin, possibly causing other damage. If you can find a spring the same diameter as the original firing pin spring, shorten it to a length that will just hold the pin forward enough so the hammer can get behind it and see if this shows signs of being the right path.

As far as reshaping the tip of the firing pin of this design, I think this may demonstrate why this would not be a good idea...

Here is a photo of a pair of bolts from a single shot, open bolt design pistol. The hole is where the ejector pokes through to knock the empty case out of the ejection port and the "bar" is actually the firing pin.

http://i187.photobucket.com/albums/x308/kennyrolling/post-3-51685-image0032.jpg

When the trigger is pulled, the sear releases the bolt, it slams forward and makes a nice crease accross the back of the case, discharging the round. The pressure from the round expells the bullet out the front and the empty case pushes the bolt rearward where the sear catches it. Here's a video of this gun working...

http://www.youtube.com/user/Fuzzybeanerizer#p/u/3/sExt7ScAVWM

My fear is that as the design of this conversion would "run away" if the firing pin were sharpened in any way.

[BigBoy1]

Thinking about this a bit more...

Regarding my suggestion of trying it without the firing pin spring, I think just removing the spring would allow the firing pin to travel rearward so far that it may cause other problems, namely the two halves of the bolt no longer being joined by the firing pin and also, the firing pin resting so far back that the hammer hits the bottom of the pin, possibly causing other damage. If you can find a spring the same diameter as the original firing pin spring, shorten it to a length that will just hold the pin forward enough so the hammer can get behind it and see if this shows signs of being the right path.

As far as reshaping the tip of the firing pin of this design, I think this may demonstrate why this would not be a good idea...

Here is a photo of a pair of bolts from a single shot, open bolt design pistol. The hole is where the ejector pokes through to knock the empty case out of the ejection port and the "bar" is actually the firing pin.

When the trigger is pulled, the sear releases the bolt, it slams forward and makes a nice crease accross the back of the case, discharging the round. The pressure from the round expells the bullet out the front and the empty case pushes the bolt rearward where the sear catches it. Here's a video of this gun working...

My fear is that as the design of this conversion would "run away" if the firing pin were sharpened in any way.

I tend to disagree with the slam-fire concept. If you look at the picture of the bolt face, there is a pocket in which the base of the case sits. The depth of this pocket recess is 0.045" while the thickness of the case rims are 0.040". The non-recessed surface of the bolt touch the base of the barrel so there is 0.005" clearance between the rim of the case and the barrel. If the clearnce was zero, then I would expect a slam fire to occur.

Also, with the current hemi-spherical shaped firing pin, when the case is pushed from the magazine into the chamber, the rim of the case pushes on the rounded underside of the firing pin and moves it the rear.

I have no intension of reshaping the existing firing pin. I've made two completely new ones and will use those for any reshaping of the tips.

I agree that it is a unusual design. I'll try to find a spring that I can put on the front of the firing pin so it will not be in contact with the rim and the hammer will have to strike the pin and compress the spring to fire the case.