All:

I am about to try and improve the trigger on my Model 70 with just the smallest amount of judicious stoning of the trigger/sear engagement surfaces, and was wondering about how much the two surface "should" engage by.

I am not going to attempt to monkey with that spec, but was doing some on-line searching and couldn't find a specifcation on that. The trigger does have a bit of creep to it, and so I thought I would take a look at, and measure the engagement of the two surfaces to determine just how much it may, or may not, deviate from "ideal" specs.

If this level of work was required, I would be sending it off to a professional.

TIA,

Bob

Hmmm...no replys...

Well, I will update with my results etc.

So I ever so lightly stoned the trigger & sear surfaces with 300 followed by a 400 stone and reassembled to get a 1.5 lb pull with the return srping on the trigger removed, so adjusted the spring to add another 1,5 lbs, making a pretty clean 3.0 lbd trigger.

It is much better than the 4.5 lb prior.

I measured the trigger-sear engagement as best I could, and it looks like there is right around 0.025 of overlap/engagement. Did not monkey with that, and it passes the drop test so I think all is well.

Any thoughts at all on what a "proper" trigger/sear engagement spec is? Just curious at this point.

Thanks,

Bob

There are many ways to improve the trigger pull on a M70. You do have to be careful how much material you remove or change because it can prevent you from engaging the safety when the bolt is cocked. A .025 sear engagement should be okay, and with a trigger pull weight of 1.5 lb without the trigger return spring, you certainly haven't gone too far, yet.

May I ask from what height did you perform the drop test?

quote:

Originally posted by Westpac:

May I ask from what height did you perform the drop test?

More importantly, was it dropped on the muzzle end?

Westpac-

Thanks for taking the time to share your expertise!

I am aware of some of the pitfalls with such work, such as the potential safety issue. That is why i was attempting to emphasize that I lightly stoned the surfaces. I did it just to the point where I could see some polishing of the surface and did not try to remove all of the tooling/machining marks. Did not want to remove much, if any material.

The safety still operates just as smoothly.

I used to correspond and talk with a well-known, and now deceased, riflemaker who "mentored" me in some of my hobbiest gun tinkering, and he taught me that I need to add enough spring tension to double, at a minimum, the pull weight with the spring removed to have a safe and "balanced" trigger in the m-70.

I am right about 3lbs now, though it is a tad inconsistent with the occasional 2lb 15 oz to 3 lb 8oz break, but I can live with that...for now. Above all else, I want it to be safe.

As mentioned, I did not do anything to modify the sear engagement, and I am pretty certain that this was bone-stock original. My best attempt to measure it looks like it is around .025 in. Still have a very, very slight creep to it, but again, I can live with that, for now...Any more will require a trip to a bonafide pro.

My drop test...this is a p-64 fwt, and I refinished the stock and added a decelerator, so I dropped it on the heel of the pad about 8-10 times from about a 12 inch height on a concrete floor. Didn't drop the striker, so I felt pretty good about it.

Do you think that test is "aggressive" enough?

Best,

Bob

quote:

More importantly, was it dropped on the muzzle end?


Z1R - you are kidding, right? Sarcasm is sometimes difficult to "get" with a keyboard...

quote:

Originally posted by Blackbart2:
My drop test... I dropped it on the heel of the pad about 8-10 times from about a 12 inch height on a concrete floor. Didn't drop the striker, so I felt pretty good about it.

Do you think that test is "aggressive" enough?

Best,

Bob

The real test will come if you happen to stumble in the field and have to use the butt stock to break your fall.

I hold the cocked gun with both hands and drive it's butt end into the concrete deck. I do that about 3 - 4 times. Of course I attempt to take the necessary precautions not to damage the stock while doing it.

The trigger also must also hold if the rifle were leaning against an object and then suddenly fell, landing on it's side. I test this by holding the rifle on it's side and then using a closed fist to administer a moderate blow to the to the are of the grip.

Then there is the "I can't believe I missed the F@#king shot" test, where you grab the barrel with both hands and beat the rifle into the ground.

Westpac-

Thanks again..

I did do exactly what you suggest - hitting the stock in the grip area...nothin.

Also, when I had the bbld action out, I cocked the striker and hit the side of the action with a soft rubber hammer...again nothing.

Hopefully, when I subject it to the last test you mention, it will, in all likelihood, have been been discharged already.....