I was hijacking the liner thread, but decided it would be best to start a new thread for this topic.   

I make the trigger springs for rolling blocks that are sold by rollingblockparts.com.  I decided to make one for the Hepburn also, as they are similar.  I made one tonight, and it works perfectly for my Hepburn.  I was able to safely take mine to 2 pounds 10 ounces by making a correct spring.  It is very crisp and quite good, but that's as light as it will go without messing with the sear geometry. 

I only have two hepburns with single triggers to experiment on, and need a bit more data if I can ask anyone with a hepburn for some help.  Can anyone with a hepburn measure the pull on your trigger when the hammer isn't cocked, and the weight when the hammer is cocked?

The reason for asking you for your measurement; mine measures exactly 4 oz without the hammer cocked.  I don't think I can go safely less than that; that's very minimal, but it works positively and won't accientally discharge, so it is fine.  The thing I am getting at is that based on my rifle, the pull weight on the Hepburn can be reduced by the difference in what the uncocked weight is now, and 4 ounces.  Anything more than that is in the sear.  I only have two hepburns to experiment with, I wanted to expand my data pool if I can.

Thanks,
dave

Dave - have only the one single-trigger Hepburn and my uncalibrated finger tells me ~1# pull with the hammer down and a very tough 7-8#, maybe more, with the hammer fully cocked. I'll see if I can borrow a trigger-weight gauge this week to check.

In talking to John King, who makes RB trigger springs, it was his thinking that at some point in time someone put the considerably heavier RB spring in my Hepburn, as the RB spring drops in, but is considerably heavier. 

Dave, my trigger return spring moves at exactly 4oz. and with my trigger job, the hammer falls at a crisp 2lbs.  I like the single Hepburn trigger and as you know, they're easy to work on.  Bob

Dave;
My single trigger Hepburn is much like Bob's, a little heavier on the return spring and a trigger weight @ 2.6/7 # but very crisp with no creep.  Easy to shoot.
Work was done by John Taylor.
Cary

SSS,  If you are used to shooting a set trigger and haven't put a trigger pull gauge on it your 7-8# guess may only be 2-3#. Buy John King's Hepburn return spring and put it in.  Why play with something you don't like?

Guys, thanks for the data.  Based on your data, and measuring my two, I think it's a fair conclusion that the trigger spring on a hepburn contributes somewhere around 12 ounces to the trigger pull.  I was able to drop that down to 4 oz with a replacement spring.  An 8 oz improvement, but that's not as dramatic as the 10 pounds or more that drops off a rolling block when you replace the spring.

I took the whole thing down tonight, cleaned and degreased, and then lubed it everywhere with moly powder.  The final pull weight was 1 lb 3 oz.

I started this with the pull weight at 3 pounds 2 oz.  The replacement spring I made dropped it to 2 lbs 10 oz.  Cleaning and lubing with moly dropped it further, down to 1 lb 3 oz.   

So, a replacement spring will drop it 8 oz.  Cleaning, moly will drop it 1 lb 7 oz.  I'd do a thorough cleaning and moly lube job, and then if it still isn't where you want it to be, take another 8 oz off with a replacement spring.   

I thought the pull was crisp when I started.  Lighter, and even crisper when I finished.  I'm happy with this trigger!

dave

dave - did you leave the sear contacts dry when you did the cleaning & lube? Your results are forcing my hand. I have to use both thumbs to cock my Hepburn, so could well be very dry inside. Especially with the considerably wider hammer/trigger resulting in a larger pin contact area. Time to dig out the latex gloves and moly powder. Hopefully, can get to it today.

OK........ not being able to contain myself, went downstairs and pulled out the tang and too a look at things. Everything 'looked' well lubed with oil, but to be certain I pushed the trigger pin out and lubed again, added some lube (Breakfree) to the hammer and roller pins and put just a bit of high-pressure grease (same as I use on the M-1 & AR) on the top of the hammer spring where it rubs and the roller runs. Put it back together and would say (based on my uncalibrated finger) that the pull is now about half of what it was. Perhaps it was a bit dryer than it looked. But, if dave's spring will gain another 8oz, will be happy to have as it is still too heavy for my tastes. And, it still takes both thumbs to safely cock the hammer, which I really do not mind. Positive ignition is good thing.

With the rebounding hammer (deHaas gives details on how to remove the rebounding feature if one wants), is there any problem with dry-firing the Hepburn?

My hammer spring certainly looks like the one in de Haas book. And, I might have particularly weak thumbs. But, who knows with an old rifle. Do need to do some more shooting with it to see if the frees up the trigger a bit more. All indications are that it will be a fine shooter when I do my part.