mis-fires
mis-fires
1911 Sterllingworth 16ga. completely redone several years ago has started to mis-fire. At first it was one in about 50 shots, and all from the right side. Now the left has the same problem. Inside, the gun is clean and there are no binds or hang-ups. It happens with several brands of primers. I have only owned the gun for about 5 years. In the past could a cocked gun for, say, 30 years have created a set in the hammer springs? Would it be worth the effort to pursue new hammer springs? Any and all guidance is appreciated. Dick Baum
Shoot right at 'em
-
fox-admin
- Site Admin
- Posts: 3755
- Joined: Fri Jan 05, 2007 4:46 pm
- Has thanked: 491 times
- Been thanked: 1308 times
Fox-Admin: Yes, in one case I struck it four times in the right barrel and three times in the left, without firing, then tried it in a Parker and it fired on the first try. This was a Rem. primer. I also had two mis-fires with RST factory shells. In both cases the dented primers later fired in the left barrel. I have over 3000 rounds through the gun in the last several years without problem. Firing pins appear to protrude through the standing breech far enough. Logic left me with weak springs, but apparently not. What could be the culprit??
Shoot right at 'em
-
Silvers
- Posts: 4766
- Joined: Sat Jan 06, 2007 9:28 pm
- Location: Between Phila and Utica
- Has thanked: 836 times
- Been thanked: 1185 times
I really doubt the hammer springs are too weak. Here's what I would check:
1. Protrusion of the hammer tips (firing pins).... the Fox factory protrusion should be about .055-.060" from the breech face. It's easy to check with a vernier caliper or a depth mike. Possibly the gent who reworked the gun shortened the tips to make it easier to open with any/all brands of ammo?
2. Are the rim recesses cut too deep? That would allow the shells to sit deeper in the chambers. You can see that if you put a 6" precision scale across the breech of the unmounted barrel set to check the gap between the shell base and the face of the barrels. If the reworker did some chamber work with a reamer that could have deepened the rim recesses. This scenario would have the same effect as a short hammer tip(s).
3. I've had factory shells that have concave bases due the primer seating machinery being out of adjustment. The last batch I ran into had 2 or 3 bad shells per box. Handloaded shells can be suspect also if the loader is feeling his oats when seating the primer. The next time you get a misfire, save the shell, don't try to fire it in the other barrel or another gun, and hold a precision scale against the base... see how much daylight you can see between the scale and the primer. If you can see a lot, that's likely your answer... same effect as a short firing pin tip or a too deep rim recess.
Silvers
1. Protrusion of the hammer tips (firing pins).... the Fox factory protrusion should be about .055-.060" from the breech face. It's easy to check with a vernier caliper or a depth mike. Possibly the gent who reworked the gun shortened the tips to make it easier to open with any/all brands of ammo?
2. Are the rim recesses cut too deep? That would allow the shells to sit deeper in the chambers. You can see that if you put a 6" precision scale across the breech of the unmounted barrel set to check the gap between the shell base and the face of the barrels. If the reworker did some chamber work with a reamer that could have deepened the rim recesses. This scenario would have the same effect as a short hammer tip(s).
3. I've had factory shells that have concave bases due the primer seating machinery being out of adjustment. The last batch I ran into had 2 or 3 bad shells per box. Handloaded shells can be suspect also if the loader is feeling his oats when seating the primer. The next time you get a misfire, save the shell, don't try to fire it in the other barrel or another gun, and hold a precision scale against the base... see how much daylight you can see between the scale and the primer. If you can see a lot, that's likely your answer... same effect as a short firing pin tip or a too deep rim recess.
Silvers
Last edited by Silvers on Sun Jun 24, 2007 9:57 am, edited 1 time in total.
Miss-fires: The jury is still out. Miss-fires only started after I had the gun re-done and had put through at least 3000 rounds without mishap. Mike Orlen did the barrel work and the rims do not appear to be recessed, also the firing pins seem to protrude enough, also testimony has been given that hammer springs don't take a set. I am now looking hard at hulls and primers. Maybe it's some odd combination. I just wish it would go away, as mysteriously as it arrived. Dick Baum
Shoot right at 'em
-
BillJanssen
- Posts: 8
- Joined: Fri May 11, 2007 4:23 pm
- Location: Cedar Hill, Missouri
Dick:
I've seen this same thing happen on two different Foxes, one was my 20 SW and the other was my pal's 16 SW. Mine was a new acquisition but my buddy had been shooting his for years without problem, like yours, it just started happening mysteriously.
In both cases the misfires were on account of light primer hits and occured randomly only with certain brands/lots of shells and with the same bbl. I can't remember which brands/primers did and didn't. On both guns we carefully checked headspace/rim thickness and firing pin protrusion compared to other "fully functional Foxes" and they seemed okay, we also cleaned and checked the pin holes and hammer travel spaces for crud, burrs and other boogers...this made no difference, we still had misfire issues.
New mainsprings were the fix for both. I can't tell you where to get them. I had no luck with Numrich of Wolff's, they're oddball springs. Our local gunsmith let me root through his cache of old springs. He has enough old springs to overload a minivan. After sorting out 17 gazillion springs I found a couple the right dimensions that worked.
Good luck!
Bill
I've seen this same thing happen on two different Foxes, one was my 20 SW and the other was my pal's 16 SW. Mine was a new acquisition but my buddy had been shooting his for years without problem, like yours, it just started happening mysteriously.
In both cases the misfires were on account of light primer hits and occured randomly only with certain brands/lots of shells and with the same bbl. I can't remember which brands/primers did and didn't. On both guns we carefully checked headspace/rim thickness and firing pin protrusion compared to other "fully functional Foxes" and they seemed okay, we also cleaned and checked the pin holes and hammer travel spaces for crud, burrs and other boogers...this made no difference, we still had misfire issues.
New mainsprings were the fix for both. I can't tell you where to get them. I had no luck with Numrich of Wolff's, they're oddball springs. Our local gunsmith let me root through his cache of old springs. He has enough old springs to overload a minivan. After sorting out 17 gazillion springs I found a couple the right dimensions that worked.
Good luck!
Bill
-
fullchoke16
- Posts: 426
- Joined: Fri Jan 05, 2007 11:17 pm
- Location: Western PA
- Been thanked: 1 time
Dick, check Popperts Gunsmithing, Glenside,PA. Their website is www.poppertsgunparts.com. They may have some. Fred
Recoil is most noticed when I miss
-
Dick Jones
- Posts: 31
- Joined: Mon Feb 12, 2007 1:55 pm
- Location: NC
There is a company named Lee Spring Co. I would be stunned if they didn't have a workable spring for the Fox Mainspring. They have more springs than any source I have seen and I have used them for unusual springs for machines.
I don't have a cataloge now but they are in Brooklyn NY.
Try them. I'll bet they have the springs for the lever stop as well.
Best, Dick
I don't have a cataloge now but they are in Brooklyn NY.
Try them. I'll bet they have the springs for the lever stop as well.
Best, Dick
Mis-fires: and the jury is now in. It was hammer springs that were weak. Oddly enough they did not show any decrease in length. I got lucky and obtained new springs that had never been in a gun, and they were exactly the same length as the originals. I would have thought they would take a "set" and shrink some, but they just lost their "springiness". Bobby alerted me to the difficulty of assembling tough springs and he was right on. The old ones nearly fell in place by themselves, while the new ones took a lot of effort. Thanks to Bill Jansen for describing the same symptoms, and to Fred, Dick, and Don for aiding in spring search. The springs actually came from a gunsmith in Conn., and he said he had other parts also. This is a great forum and without it I would still be mis-firing. Dick Baum
Shoot right at 'em
Mis-fires: and the jury is now in. It was hammer springs that were weak. Oddly enough they did not show any decrease in length. I got lucky and obtained new springs that had never been in a gun, and they were exactly the same length as the originals. I would have thought they would take a "set" and shrink some, but they just lost their "springiness". Bobby alerted me to the difficulty of assembling tough springs and he was right on. The old ones nearly fell in place by themselves, while the new ones took a lot of effort. Thanks to Bill Jansen for describing the same symptoms, and to Fred, Dick, and Don for aiding in spring search. The springs actually came from a gunsmith in Conn., and he said he had other parts also. This is a great forum and without it I would still be mis-firing. Dick Baum
Shoot right at 'em
Mis-fires: and the jury is now in. It was hammer springs that were weak. Oddly enough they did not show any decrease in length. I got lucky and obtained new springs that had never been in a gun, and they were exactly the same length as the originals. I would have thought they would take a "set" and shrink some, but they just lost their "springiness". Bobby alerted me to the difficulty of assembling tough springs and he was right on. The old ones nearly fell in place by themselves, while the new ones took a lot of effort. Thanks to Bill Jansen for describing the same symptoms, and to Fred, Dick, and Don for aiding in spring search. The springs actually came from a gunsmith in Conn., and he said he had other parts also. This is a great forum and without it I would still be mis-firing. Dick Baum
Shoot right at 'em