I got a call Friday from a good old friend. He bought a H&R a couple years back on my suggestion. Its a very pretty stainless Cinn thumb hole 45-70.
Seems he has been having occasional failure to fire problems since day one. Seems it was the last straw when a nice buck stepped out on the last day of the season and he had three clicks and watched the deer walk away...
He dropped it off yesterday for me to look at...
First off, I tired a couple primed cases, sure enough just click. (Very light hits) Then I checked head space by feeling and looking at the case fully seated in the chamber. It was about .002-.003 below flush, so a little deeply chambered. I then checked the proper function of the disconnector. (transfer bar) It was standing tall and even tryng to short pull the trigger it was working just fine. Next I checked pin protrusion. It was .025. Again, a lil short... I tore the action apart. In doing so I found the latch barely engaging the shelf... I am talking about 15-20% engagement. First I took .020 off the hammer face to allow the firing pin more travel. I re assembled the action with a bit of anti sleeze and a Wolffe HD spring.
Then I looked at the barrels shelf. I stoned the shelf square and re checked engagement. It was a bit better but still only at about 25%. So, I filed off a couple thousandths more and stoned flat and square again. Now I have about 60-65% engagement, much better.
I sized and primed six more cases and test fired, every one went bang and was left with a positive deep firing pin strike.
I called my friend back and explained what I found. He stopped by today and picked it up, he was happy as my first thought was a disconnecter. I did not think I had any, but I did find a couple of them. Just did not need them.
ALL FIXED!
CW