As I’ve been putting together tooling for a 1911 build I’ve became interested in the different sear jigs available - there are numerous choices. I’ve had a Ed Brown for some time and it seams to work fine but I don’t like the fact that you have to freehand the escape angle. If you’re careful you can keep the escape angle square to the primary angle but there’s no guide to help establish and maintain the angle. I have read about the Tru-radius jig and it makes a lot of sense to me. I decided to make a set and I made them from .405-.402. I like the fact that the primary angle is consistently neutral and you do get a guide for the escape angle. I’m interested to hear what others think of the tru-radius especially if you’ve used it, or any of the other sear /hammer jigs for that matter.
I would like to hear about the Tru-radius jig as well. It has always intrigued me. I just might have to purchase one and do a video on it.
Generally, I don’t like to mess with sears. In my 1911s, if I want to get a better trigger pull I yank out the guts and put in cylinder and slide components in and I don’t have to mess with a jig. But the tinkerer in me totally wants to buy some jigs and play.
I have a Power custom Series I Stoning jig. I do like it. It is built solid and will last likely forever. It is a simple design. It’s easy to use and there are many different firearms that you can buy the adapters to work on. For my build 1, I wanted to do all of my own sear and hammer work to make my trigger job truly mine.
- Easy to use and gets good consistent primary and secondary angles for your sear.
- Does not do hammer squaring or polishing only sear work.
So for my build 1, I used this jig and it was quite easy to use. There is a document on doing trigger work for sear and hammer on brownells https://www.brownells.com/guntech/2-lb-trigger-pull/detail.htm?lid=10297
That article is pretty easy to follow and provides good advice. You may not need a 2.5 lb trigger but its easy to make a great 3 lb trigger if that is what you want by simply bending the sear spring appropriately.
So what I found was key to a good sear hammer job is
- I used the hammer and sear pin set that allows you to see the hammer and sear relationship directly on your frame
- I used a digital microscope to be able to see the primary and secondary angles in relation to the hammer. This is key and is difficult. You have to have something otherwise you are cutting blindly. Some people you the Yavapai Sear tool which includes a microscope with the sear and hammer pins. The comments on that product on brownells by several people state that the pins are “off” and the relationship may not be true to what it is on your firearm. However the microscope does allow you to see your primary and secondary angle well but you would likely have to check it on the frame directly with the above mentioned pin set in #1.
When I used this set up again it went pretty easy for the primary angle the secondary angle took longer because you keep checking it until you get it where you need it.
Hammer: The power series I can stone the hammer to proper height using a stone and a feeler gauge. I was fortunate my hammer was proper height and was square so I ended up not doing anything to it. I would like something to stone and or polish the hammer to make sure it is square but the Series I doesn’t do that. The BOB MARVEL 1911 AUTO SEAR & HAMMER JIG does easily allow polishing and squaring of the hammer and does sear work as well. However, read the reviews, a few people have posted trouble with one of the screws that holds the sear, it comes out or is not tight enough. But I may eventually get it to have the option of polishing the hammer hook.
In the end, I was able to achieve a 2 lb 10z crisp trigger pull.
I wish you luck. If you get more info on the Tru-radius please post . Harrison and Design make some great products.
@pc1911 I saw your thread where you used the digital microscope. I’ve already ordered one similar just been waiting on it to show up. That was a great idea. The Power Custom seem to be the go to for gunsmiths that want to do trigger work on a variety of guns. I’m attempting to make all of my own tooling so the Power Custom was kind of out the picture. That’s one reason I decided on the Tru-radius, plus the theory behind the Tru-radius seems really sound. I have already bought the Bullet Proof sear and hammer. The sear doesn’t have enough meat on it to use the Tru-radius. If I want to use the Tru-radius I’ll have to buy another one from Harrison’s or EGW that leaves material for finishing. If decide to keep the Wilson sear I’ll stone the primary with the Ed Brown jig which I already have and use the Tru-radius radius for the escape angle.
I used the Tru-radius jig to gauge the squareness of the sear pin hole to the primary angle on the Wilson sear and it is exceptional. It has to be square within a tenth or two. The sear really only needs polishing and an escape angle stoned.
As far as the hammer I’ve not developed a plan for that yet. If it did need squaring or much hook height adjustment I’d use my mill to clean it up. Once again though the Wilson hammer appears to only need polishing. I need to inspected it further to verify but from preliminary checking it appears to be machined square and the hammer hooks seem to be about .022. I’ll want to take about .002 off the hammer hooks.
At any rate I still have a lot of jigs and fixture work to complete before I get to that point.
Thanks for your input
My pleasure to help. I am jealous you have a mill and sounds like the experience and know how to use it.
Yes in terms of hammer polishing or squaring the marvel jig would work well. If you make your own tooling, you might take a look at the marvel. The design for the hammer part looks fairly simple and might be possible to make your own version for polishing.
You might also check Ebay. You never know you might find a used version of the Power custom jig.
Is anyone still looking for the Marvel sear and hammer jig?
Please PM me your price
Please PM me @Robert price so i can outbid him.
Easy buddy, back off,
tell ya what, lets be friends, you back off and I’ll send you a slightly read book on Flint knapping for arrowheads…
Ok Chief ?
Okay maybe this time