hammer extension causing misfires???

[JBC]

 Has anyone had misfires because of their hammer extension? The reason I ask is that I have exausted all other possibilities that I can think of. I have plenty of firing pin portrusion and I have tried 3 brands of brass and 3 brands of primers and 2 factory loads in my 45/70 handi and I still get about 20% light strikes the other 80% are good solid hits and yes I hold the trigger back till after the shot - as a matter of fact during my testing I have been banging the trigger like a shotgun and holding till way after the shot. Now thinking back the only time i can remember not having misfires was when I was shooting iron sights i.e. no extension. I know I need to test more without the extension but I wondered if anyone has had this problem before me.

[yukondog]

could the extension be hitting the scope,weak hammer spring,hard primers?

[JBC]

the extension is a long way from hitting the scope and I tried three brands of primers so I dont think that could be the problem but the hammer spring could be weak I suppose but the gun is less than a year old and only has a couple hundred rounds through it max

[quickdtoo]

Replace the hammer spring, they can weaken after a couple hundred rounds.  You can return it to H&R for repair or do it yourself, see the trigger hone info in the FAQs for how to info. Springs can be ordered from H&R, Brownell's, Numrich and Wolff.

Tim

http://www.brownells.com/aspx/ns/Schematics/SchemMFG.aspx?schemid=676

http://www.gunsprings.com/

http://www.e-gunparts.com/dept.asp

http://www.hr1871.com/documents/manuals/HR_NEF_HANDI_RIFLE_MANUAL.pdf

[Steve P]

You can also confirm your action is closing all the way.  Does your scope base extend onto the frame?  Is it keeping the action from closing the same every time?  Scope and base were added before mis-fires started, weren't they?  Check your action lockup and make sure you use the same momentum and force each time you close it.

Hammer extension will wear out springs and break hammers.  Never heard of one causing a misfire, until it weakended the spring or broke the hammer.

Good luck. 

Steve 

[Singleshotsam]

I had the same problem on my survivor .308 and my Rossi .243.  Got pissed, took it off and tossed in in my scrap pile and have had no problems since.  My theory is that the hammer is designed to work as is.  You throw a couple oz. hammer ext. onto a spring that wasn't meant to hold it and that takes away from the centrifugal force to strike the pin. Both guns were brand new and having this problem, so worn springs were not the issue in my case.

Sam

[JBC]

Thanks guys. and Sam I think you might be right about the extra weight. I need an extension to reach the hammer but I think I might toss the big H&R one and bob my hammer a bit and drill & tap the side of it for a newer winchester 94 style thread in style which is much lighter and more compact. I think if I take some off the hammer I can keep the weight down to less than the original hammer without an extension

[quickdtoo]

Been there, done that, just don't forget to anneal the hammer spur before drilling. 

Tim

http://www.gboreloaded.com/forums/index.php/topic,86991.msg525441.html#msg525441

[JBC]

Thanks for the heads up tim, I was wondering how hard the hammer was because if it was soft I could just drill & tap but actually I am a cnc edm operator so I can use my machine a work to burn and tap holes in hard steel. It uses high voltage low amperage current to erode away the metal, kinda like arc welding without the filler rod but much more controlled. My job is a real pain most of the time but it does have it's benefits for projects like this

Thanks,
Joe

[quickdtoo]

Perks of the job works!! 

Tim