Light firing pin strikes

[Stan Hillis]

I was trying some new-to-me shells today, B & P Competition One 12 ga., one ounce #8s at 1160 fps. These factory shells are under 6500 psi, so I felt they would be a great alternative to reloads for clays and doves. Well, after shooting a round of clays with my Perazzi I unlimbered the 1918 12 ga. BE Fox with 32" barrels to try on the five-stand. It's a particularly good shooting gun for me on doves and clays, and I was anxious to give it a try with the new shells. Was I ever surprised when the second shell misfired! I looked at the primer .......... light hit. Swapped it into the other chamber, reloaded, and both barrels fired that time. This went on the whole round of 25, with maybe a total of 10 misfires out of 25. Every shell would fire on the second try. The shells break birds hard, and I like them a lot except for the misfires.

Understand that I have shot this gun for several years with RIO one ounce loads with never a misfire, until today. I recall many years ago shooting some B & P shells in a Beretta 682, and they would often get underneath the ejectors causing much consternation to remove from chamber. That didn't happen with the BE, but I'm wondering if the shell's rim diameter, and/or thickness, is a bit under that of other brands I've used, which could cause them to sit a tiny bit deeper in the chamber and lead to light firing pin strikes. I intend to try to get the time to do some measuring of them tomorrow to see.

Question for now is, have any other Fox brethren ever had this issue with B & P shells?

Thanks, SRH

Edit to add: The misfires were not always on the right barrel, but the most prevalent there.

Also, if I am wrong on the head/rim diameters being smaller on the B & P shells, is there a way to accurately measure firing pin protrusion without removing the buttstock?

Thanks.

[fullchoke16]

deleted

[Silvers]

Let's remember that A H Fox "firing pins" are the tips of the hammers and that the hammers strike/rest inside counterbores in the frame and were not designed to be rebounding. Hence the tip protrusion may be easily measured with the barrels off the frame and the hammers not cocked. In comparison the separate firing pins on your Perazzi are free to drive forward when struck by the hammers, to the full depth of their seats in the frame.

If you don't have a depth mike to measure protrusion on your Fox, the depth rod on a regular dial caliper will do nicely. Factory protrusion will be about 50 thou from the breech face but I've seen Foxes fire reliably with replacement hammers and as little as 40 thou. I'll add here that It's rare to have a misfire attributed to a weak Fox mainspring (owing to the long hammer throw) and IME they're almost always due to something else. Regarding the B&P ammo, I've never fired factory B&P shells in a Fox but I've picked up a few hulls on courses to test reloading them and they always fired just fine with Cheddite or Fiocchi primers. I haven't measured their rim diameter or thickness to compare with US made shells. Stan, since your BE Fox fires reliably with Rio shells I'd say the problem with B&P's is likely to be marginal headspace in your gun, deep seated primers, or both.

frank

[Stan Hillis]

Thanks for the replies.

I thought that the hammers/strikers on a Fox when at rest were at full protrusion, but what you said, Frank, reassured me that it was thus. I first measured the firing pin protrusion with my depth mike and got .051" and .052", which is plenty. I then turned my attention to the B & P shells I was using. Thinking the rim/case head diameter might be less than other brands, I measured some of them with a dial caliper. Using the "knife edge" on the ends of the calipers I measured the diameter of the case head just underneath the rim. The knife edge allowed me to get accurate readings tight underneath the rim, without the rim itself interfering with the measurements. What I suspected was right. The rim thicknesses are very near the same on several brands, but the diameter is different on the B & P shells. Here's what I found:

B & P .795"
Estate .805"
Clever Mirage .808"
Super X .801"
RIO .806"

I believe the taper underneath the rim of all shells combined with the smaller diameter of the head of the B & P shells allows them to fall a bit further into the chamber, thus creating too much headspace, and correspondingly too much distance for striker to travel to reach the primer and hit it a stout enough blow to detonate it.

Addressing how deeply the primers are seated, I took measurements on that, too. Using a depth mike I measured the distance from the surface of the case head to the surface of the primer. Survey said ..........

B & P .004"
Estate .008"
Clever Mirage .010"
Super X .005"
RIO .007"

So, you see that the primers are seated nearer the surface of the case head in the B & P shells than the others, which should help the problem, but doesn't. The only reason I see being that the B & P shells fall so far into the chambers that the shallower primer seating is not enough to overcome it.

So much for being able to use them in that gun. I guess I'll try them in some of my other vintage doubles and see how they work.

All my best, SRH

[Mike of the Mountain]

Stan, just use those shells on those overhead targets where your muzzles are facing the sky. See, problem solved!!

BTW, thanks for posting your findings. Plenty of shooters have that same issue with various shells. Good to know.

[Stan Hillis]

I've been mulling this over in my ol' bean for a while. The firing pin and the hammer are one piece in a Fox. When in the fired position, as I understand it, the hammer "boss" rests against the backside of the receiver where the firing pin holes are drilled. so, the amount of firing pin protrusion depends upon how much it is "proud of the hammer". So, to take this a step further, couldn't the firing pin protrusion be increased slightly, and precisely, by relieving the hammer boss by an equal amount all around the firing pin, or striker, as it were?

SRH

[Mike of the Mountain]

Maybe one firing pin has some extra wear on it from 100 years of shooting. Did you measure both firing pins? Mabe it is the difference in firing pins and maybe a difference in the thickness of the standing breech by the firing pin holes? I'd just change shells before I'd start fiddling around with milling any parts on a gun that fires other brands of shells reliably.

[Stan Hillis]

Thanks, Mike. I'm not about to go messing with the BE just because it won't shoot B & P Comp One shells without misfiring. I have shot other brands in it with no problem for years. Read earlier in the thread and you will see where I determined the problem with the B & Ps.

I just started thinking about the mechanics and got to wondering how insufficient firing pin protrusion is remedied on a Fox. I can think of only two ways .........the one I mentioned, and tiging additional metal to the tip of the striker and dressing it down. It's just the mind of a farmer, trying to figure ways to improve or fix things, I guess.

All my best, SRH

[vaturkey]

Responding to this because my late Savage made 20 gauge Sterlingworth with factory 2 3/4" chambers won't fire B&P shells out of the right barrel. Just found that out while in Michigan. It of course will always fire RST shells and I've never had a problem with Federal shells either. Little dent in the B&P primers, but they won't go boom. Those shells will now be relegated for use in my fathers' old Winchester 101 which will shoot anything. PS. The B&P shells also chamber pretty snuggly in my sterly. Don't have that issue with any other factory shells.

[Mike of the Mountain]

Stan, another of our clients has the same issue with B&Ps in his Winchester M21 28g. Misfire in one bbl while any other brand works fine.

[Shelldrake]

My Savage-era 20 ga Sterlingworth will occasionally give me light right barrel strikes with reloads. While grouse hunting in Maine last week, I had two right barrel light strikes on the first afternoon with RST 2 1/2" shells. Of course, both situations were wide open opportunities!

Dan Rossiter says these issues are either typically minimum firing pin protrusion or a short hammer strut. I will be sending the gun to him for repair.

Matt

[bbman3]

I have noticed that on some older doubles that have been shot a lot the right barrel are slightly off face more than left because using the right barrel for more shots. Bobby

[Stan Hillis]

Thanks for the follow up replies. I've been a bit out of the loop for several days following a bike accident, Thur. Oct. 19, which has left me with some pretty severe road rash, swelling, bruising and cracked or badly bruised ribs, all on my left side. A "semi" shot out into the highway just in front of me, and blocked my lane, causing me to have to attempt an evasive maneuver to avoid a headlong collision with him at 50 mph. I avoided that, but went down on my left side and me and the 1100 Shadow skidded aways on the highway before sliding off onto the shoulder. Six hundred pound cruisers are great for straight line and easy curves, but aren't designed for that kind of evasive tactics. I'm healing great, still picking peanuts everyday, but moving a lot more slowly and carefully as the soreness gradually improves and the healing progresses. Going to get my dozen or so stitches removed tomorrow morning.

I've not pursued the problem with the B & P shells any further yet, but will when work and agility permits. Again, there's never been a misfire in that gun with any other shell I've ever used besides the B & Ps, but I intend to try some of the others in it again just to make certain of that. I will then delve into it deeper to determine if there is indeed a very minor problem with the gun, that only shows up with that brand, or if I have a problem with that brand in any of my other 12s.

To good shooting, SRH

[Mills]

Stan. . . Again, I am glad you are ok.

I have had a similar problem with shells not firing in my Super Fox. Brad Bachelder tweaked it a few times and it seems to be working now. It was a frustrating problem

[Stan Hillis]

Today I went to a dove shoot, which was not "great shakes" due to the dreary, cloudy weather. The doves had mostly all fed before we arrived at 2 pm, but there were a few flying very high to test our mettle. It being rainy and messy I decided to take a more modern S x S, the BSS 12 ga. with 30" barrels, and leave the nice Foxes in a more dry clime. I also figured I would try some of the B & P Comp One shells, since I had bought three flats of them earlier. First two or three worked fine, then ........ a misfire. Open breech ........light firing pin strike on primer. Switched shells in chambers and they worked fine next time. Hmmm........ maybe it's not the old BE Fox that's the trouble after all. Any way, over the afternoon, and the expense of about 13 rounds, I had four misfires. It occurred in both barrels, and when I switched the shells around in the other chambers, all fired on the next try.

Well, it seems that the only thing I have learned it that B & P Comp One shells don't like S x Ss. And not just vintage ones, either.

SRH