Ruger 77 Mk II trigger

warbirdlover · December 21, 2011, 06:13 PM

I've sold the skeleton stock for this rifle and the Boyd's stock isn't here yet. I'm sitting looking at the barreled action and the trigger which is about 5 lbs. pull. It's one of those lawyer jobs where there are no (apparent) adjustments. Big question. Can these be adjusted either by myself or a gunsmith? It's a nice crisp trigger but it would be REALLY nice if I could get the pull weight down. I just KNOW someone in here has experience with these. Or maybe I'm just doomed to put on a Timney?

CTS · December 21, 2011, 06:17 PM

77 MK II triggers are not adjustable. I would go for the Timney myself but there are others that are cheaper.

AllenJ · December 21, 2011, 06:30 PM

I have a M77 Mark II at the gunsmiths right now getting some custom work done and when I posed the question to him he said better to get the adjustable trigger rather than a trigger job. It'll give you the ability to adjust the trigger up or down to a weight you like.

warbirdlover · December 21, 2011, 06:46 PM

I've come to that conclusion also. NOW, which is better? Timney or Rifle Basix triggers.

603Country · December 21, 2011, 06:51 PM

I've got a bunch of Rugers of various ages, but honestly haven't paid too much attention to model nomenclature, other than 'tang safety' and 'not tang safety'. So... forgive me if I'm confused over Mark II and Hawkeye, but I'm thinking that the Hawkeye is a Mark II version of the rifle. I took my Hawkeye to a gunsmith to get the trigger adjusted and he said that he couldn't adjust it, but he could replace the spring, which took the pull from between 4 and 5 pounds down to about 2 pounds. Took him 5 minutes and cost me $10. But if the Hawkeye trigger is just a later and improved (and different) version of a Mark II trigger, then maybe you can't have the same easy fix. I guess what he did wasn't really an adjustment, but it did get me to where I wanted to be.

Art Eatman · December 21, 2011, 07:03 PM

I used a Timney to replace the tort-liability trigger on my 77 Mk II. Easy do-it-yourself; the only grinding is on the safety bar. A little at a time; no big deal.

The Timney isn't as good as a Canjar, but Canjar is no longer in business. Shame. But, the Timney is okay...

ronl · December 21, 2011, 07:58 PM

I have worked on the M77 trigger before and it is not hard. I simply took the trigger apart, honed the mating surfaces and replaced the spring. It made a pretty horrible trigger pretty decent, and it took about a half an hour to do it.

Longdayjake · December 21, 2011, 08:24 PM

Um. Working on a m77 mkII trigger is one of the easiest things there is to do. They sell spring kits that will lessen the pull a little, but I just filed a little off the stock spring. Also, if you polish the trigger really well it will help a lot. Lastly, and only do this if you want a very light trigger, you can use a very very fine file to ever so slightly lessen the angle of the trigger. If you want to shorten the trigger pull a little (and this can get dangerous if you file too much) you can file the sear a little so that there isn't so much friction between the trigger and the sear. It is really easy. Let me see if I can find some instructions.

Longdayjake · December 21, 2011, 08:29 PM

There is a diagram in this thread that shows you better than I described it. It is really VERY easy to do. Just do a little bit at a time and don't get file happy.

http://www.24hourcampfire.com/ubbthr..._Ruger_M77_MKI

warbirdlover · December 21, 2011, 09:30 PM

I found this on the Rifle Basix triggers site. If I could find a lighter spring for it I could follow this easily...

http://www.riflebasix.com/RU-R_RU-MKII_Instructions.pdf

I'll have to look for sources for Ruger trigger springs and I found one.

http://erniethegunsmith.com/catalog/i22.html

For now this is what I'll do....

CTS · December 21, 2011, 09:47 PM

Very interesting.

jmr40 · December 21, 2011, 09:51 PM

There are no adjustment screws, but the Ruger factory trigger is one of the best, once it has been properly smoothed up and a lighter spring installed. I wouldn't think about replacing it, but would consider either working on it a bit myself, or having it done by someone else if you are not comfortable doing it.

I've done couple that came out pretty well.

Brian Pfleuger · December 21, 2011, 10:15 PM

I have a Jard Inc trigger on my M77 MkII. It is very good. The safety is solid and dependable, the pull weight is 13oz, advertised as 1 pound. No discernible creep, no over-travel. It was $79 I think.

warbirdlover · December 21, 2011, 10:56 PM

13 oz. is WAY to light IMHO for a hunting rifle. I won't go under 3 lbs. on a deer rifle.

Brian Pfleuger · December 21, 2011, 11:12 PM

Yes, not for a varmint gun though. Mine is in 204Ruger. Jard has several weights available and the springs are like $5

Longdayjake · December 21, 2011, 11:58 PM

I just cut a coil off of my trigger and then filed it smooth so it wouldn't stick in or gouge the action. Then I polished the sear and the trigger with steel wool on a drill bit. It turned out at about 2-1/2 to 3 lbs. It is by far the best trigger on all of my guns. You can get the trigger much lighter than that but for a hiking varmint gun it would be too light.

Scorch · December 22, 2011, 01:08 AM

Your easiest and cheapest is to buy a Wolff sear spring for the M77 Mk II (about $6). This will drop the pull by about 1-1/2 to 2 lbs just by itself. The next best is a Rifle Basix or Timney trigger (Timney has a sear and spring as well as a trigger adjustable for weight of pull). A new sear/trigger/trigger spring combo is the all around winner.

AllenJ · December 22, 2011, 09:51 AM

Sorry for this, I don't mean to hijack this thread, but Longdayjake's link shows a guy taking metal off of the sear? I was told by a master machinest and master gunsmith that you never, ever take metal off the sear as it is heat treated and the hardest part of the sear is right on the edge. By removing that you are creating a trigger that at some point is not going to operate correctly since it'll round off the edge. Thoughts?

Brian Pfleuger · December 22, 2011, 09:59 AM

Quote:

Originally Posted by AllenJ

I was told by a master machinest and master gunsmith that you never, ever take metal off the sear as it is heat treated and the hardest part of the sear is right on the edge.

I'm no metallurgist or machinist but the sear is a little bitty thing... I find it VERY hard to believe that one teeny little section of it is heat treated separately from the rest. I'd be fairly confident that it's all the same. The danger is in getting the angle wrong, not so much in making the edge "soft".

jimbob86 · December 22, 2011, 10:09 AM

Trigger pulls of less than 2-3 pounds on a gun you may be moving around with over rough terrain, sometimes in a hurry ...... are foolishness. As long as the trigger is crisp and does not require you to pull so hard you disturb your sight picture, then it is good enough.

As for cutting springs, grinding on sears and other internal trigger parts..... you are "picking up pfennings on the Autobahn" there....... saving $50 bucks so you can stand a good chance of having a ND (and you modifying the trigger makes it Negligence) and losing everything you have and are ever going to have...... that is just ....... words fail me.

dahermit · December 22, 2011, 10:14 AM

Quote:

I'm no metallurgist or machinist but the sear is a little bitty thing... I find it VERY hard to believe that one teeny little section of it is heat treated separately from the rest. I'd be fairly confident that it's all the same. The danger is in changing the angle, not so much in making the edge "soft".

There are two different kinds of hardened parts. If it is like a S&W handgun hammer, it is "case hardened", which is a soft, low carbon part that has had carbon infused into the outside of the part (with a carbonaceous product like Kasinite), to a depth of only a few thousands of an inch. The second type is a high carbon part that, when heat treated, the whole part hardens all the way through.
Therefore, it depends on if the part has been case hardened or hardened all the way through, if removing a few thousands of the outer surface will end up causing a problem.

AllenJ · December 22, 2011, 11:09 AM

Thank you dahermit, jimbob86, and peetzalilla, good answers that make sense.

Elkins45 · December 22, 2011, 11:15 AM

Second-hand info here, but I'm under the impression that the Ruger trigger parts are sintered or MIM parts and that they are surfaced hardened only. That means if you stone or file them you are exposing unhardened metal below and your great trigger will turn into an accidental discharge machine in only a few hundred pulls.

Again this is second hand, but it does explain why no gunsmith I've ever heard of is willing to stone/polish them and all recommend a replacement instead.

warbirdlover · December 22, 2011, 11:27 AM

Quote:

Sorry for this, I don't mean to hijack this thread, but Longdayjake's link shows a guy taking metal off of the sear? I was told by a master machinest and master gunsmith that you never, ever take metal off the sear as it is heat treated and the hardest part of the sear is right on the edge. By removing that you are creating a trigger that at some point is not going to operate correctly since it'll round off the edge. Thoughts?

Since I'm a retired metallurgist this could be true if the part has been "nitrided". This is a very hard, very "shallow" heat treatment. If it has been carburized or induction hardened it would be much deeper and probably not an issue. It also might just be chrome plated which wouldn't be very deep also.

The master gunsmith and master machinist told you right! Here is approximate "depths" of hardness for different heat treatments FYI. These can be varied but these are more common... Surface hardness would be HRC60+ and the "depth" is where the hardness drops down to HRC 50. The heat treatment used depends also on the steel chemistry and material type (stainless steel, alloy steel, plain carbon steel, etc).

Carburizing - usually over .020" deep
Carbonitriding - around .015-.020" deep
Nitriding - typically around .010" deep
Ferritic Nitrocarburizing - .005" deep
Induction hardening - .020+

Not a heat treatment but chrome plating - .010+

Brian Pfleuger · December 22, 2011, 11:29 AM

Well there you go! I knew there were some metallurgists around here!

Why the shallow heat treating? On some parts I can understand but it seems like on a trigger part it would be faster/easier/cheaper to just do the whole thing.

December 21, 2011, 06:13 PM	#1
warbirdlover Senior Member Join Date: December 13, 2009 Location: central Wisconsin Posts: 2,324	Ruger 77 Mk II trigger I've sold the skeleton stock for this rifle and the Boyd's stock isn't here yet. I'm sitting looking at the barreled action and the trigger which is about 5 lbs. pull. It's one of those lawyer jobs where there are no (apparent) adjustments. Big question. Can these be adjusted either by myself or a gunsmith? It's a nice crisp trigger but it would be REALLY nice if I could get the pull weight down. I just KNOW someone in here has experience with these. Or maybe I'm just doomed to put on a Timney?

December 21, 2011, 08:24 PM	#8
Longdayjake Senior Member Join Date: August 11, 2009 Posts: 619	Um. Working on a m77 mkII trigger is one of the easiest things there is to do. They sell spring kits that will lessen the pull a little, but I just filed a little off the stock spring. Also, if you polish the trigger really well it will help a lot. Lastly, and only do this if you want a very light trigger, you can use a very very fine file to ever so slightly lessen the angle of the trigger. If you want to shorten the trigger pull a little (and this can get dangerous if you file too much) you can file the sear a little so that there isn't so much friction between the trigger and the sear. It is really easy. Let me see if I can find some instructions. __________________ If you need bullets for reloading give my website a look. www.rmrbullets.com

December 21, 2011, 08:29 PM	#9
Longdayjake Senior Member Join Date: August 11, 2009 Posts: 619	There is a diagram in this thread that shows you better than I described it. It is really VERY easy to do. Just do a little bit at a time and don't get file happy. http://www.24hourcampfire.com/ubbthr..._Ruger_M77_MKI __________________ If you need bullets for reloading give my website a look. www.rmrbullets.com

December 21, 2011, 09:30 PM	#10
warbirdlover Senior Member Join Date: December 13, 2009 Location: central Wisconsin Posts: 2,324	I found this on the Rifle Basix triggers site. If I could find a lighter spring for it I could follow this easily... http://www.riflebasix.com/RU-R_RU-MKII_Instructions.pdf I'll have to look for sources for Ruger trigger springs and I found one. http://erniethegunsmith.com/catalog/i22.html For now this is what I'll do.... Last edited by warbirdlover; December 21, 2011 at 09:37 PM.

December 21, 2011, 11:58 PM	#16
Longdayjake Senior Member Join Date: August 11, 2009 Posts: 619	I just cut a coil off of my trigger and then filed it smooth so it wouldn't stick in or gouge the action. Then I polished the sear and the trigger with steel wool on a drill bit. It turned out at about 2-1/2 to 3 lbs. It is by far the best trigger on all of my guns. You can get the trigger much lighter than that but for a hiking varmint gun it would be too light. __________________ If you need bullets for reloading give my website a look. www.rmrbullets.com

December 21, 2011, 06:17 PM	#2
CTS Senior Member Join Date: November 6, 2011 Location: NE Georgia Posts: 1,070	77 MK II triggers are not adjustable. I would go for the Timney myself but there are others that are cheaper.

December 21, 2011, 06:30 PM	#3
AllenJ Senior Member Join Date: December 11, 2009 Location: Northern California Posts: 1,766	I have a M77 Mark II at the gunsmiths right now getting some custom work done and when I posed the question to him he said better to get the adjustable trigger rather than a trigger job. It'll give you the ability to adjust the trigger up or down to a weight you like.

December 21, 2011, 06:46 PM	#4
warbirdlover Senior Member Join Date: December 13, 2009 Location: central Wisconsin Posts: 2,324	I've come to that conclusion also. NOW, which is better? Timney or Rifle Basix triggers.

December 21, 2011, 06:51 PM	#5
603Country Senior Member Join Date: January 6, 2011 Location: Thornton, Texas Posts: 3,998	I've got a bunch of Rugers of various ages, but honestly haven't paid too much attention to model nomenclature, other than 'tang safety' and 'not tang safety'. So... forgive me if I'm confused over Mark II and Hawkeye, but I'm thinking that the Hawkeye is a Mark II version of the rifle. I took my Hawkeye to a gunsmith to get the trigger adjusted and he said that he couldn't adjust it, but he could replace the spring, which took the pull from between 4 and 5 pounds down to about 2 pounds. Took him 5 minutes and cost me $10. But if the Hawkeye trigger is just a later and improved (and different) version of a Mark II trigger, then maybe you can't have the same easy fix. I guess what he did wasn't really an adjustment, but it did get me to where I wanted to be.

December 21, 2011, 07:03 PM	#6
Art Eatman Staff in Memoriam Join Date: November 13, 1998 Location: Terlingua, TX; Thomasville, GA Posts: 24,798	I used a Timney to replace the tort-liability trigger on my 77 Mk II. Easy do-it-yourself; the only grinding is on the safety bar. A little at a time; no big deal. The Timney isn't as good as a Canjar, but Canjar is no longer in business. Shame. But, the Timney is okay...

December 21, 2011, 07:58 PM	#7
ronl Senior Member Join Date: December 2, 2007 Posts: 1,100	I have worked on the M77 trigger before and it is not hard. I simply took the trigger apart, honed the mating surfaces and replaced the spring. It made a pretty horrible trigger pretty decent, and it took about a half an hour to do it.

December 21, 2011, 09:47 PM	#11
CTS Senior Member Join Date: November 6, 2011 Location: NE Georgia Posts: 1,070	Very interesting.

December 21, 2011, 09:51 PM	#12
jmr40 Senior Member Join Date: June 15, 2008 Location: Georgia Posts: 10,809	There are no adjustment screws, but the Ruger factory trigger is one of the best, once it has been properly smoothed up and a lighter spring installed. I wouldn't think about replacing it, but would consider either working on it a bit myself, or having it done by someone else if you are not comfortable doing it. I've done couple that came out pretty well.

December 21, 2011, 10:15 PM	#13
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	I have a Jard Inc trigger on my M77 MkII. It is very good. The safety is solid and dependable, the pull weight is 13oz, advertised as 1 pound. No discernible creep, no over-travel. It was $79 I think.

December 21, 2011, 10:56 PM	#14
warbirdlover Senior Member Join Date: December 13, 2009 Location: central Wisconsin Posts: 2,324	13 oz. is WAY to light IMHO for a hunting rifle. I won't go under 3 lbs. on a deer rifle.

December 21, 2011, 11:12 PM	#15
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	Yes, not for a varmint gun though. Mine is in 204Ruger. Jard has several weights available and the springs are like $5

December 22, 2011, 01:08 AM	#17
Scorch Senior Member Join Date: February 13, 2006 Location: Washington state Posts: 15,248	Your easiest and cheapest is to buy a Wolff sear spring for the M77 Mk II (about $6). This will drop the pull by about 1-1/2 to 2 lbs just by itself. The next best is a Rifle Basix or Timney trigger (Timney has a sear and spring as well as a trigger adjustable for weight of pull). A new sear/trigger/trigger spring combo is the all around winner. __________________ Never try to educate someone who resists knowledge at all costs. But what do I know? Summit Arms Services

December 22, 2011, 09:51 AM	#18
AllenJ Senior Member Join Date: December 11, 2009 Location: Northern California Posts: 1,766	Sorry for this, I don't mean to hijack this thread, but Longdayjake's link shows a guy taking metal off of the sear? I was told by a master machinest and master gunsmith that you never, ever take metal off the sear as it is heat treated and the hardest part of the sear is right on the edge. By removing that you are creating a trigger that at some point is not going to operate correctly since it'll round off the edge. Thoughts?

December 22, 2011, 10:09 AM	#20
jimbob86 Junior member Join Date: October 4, 2007 Location: All the way to NEBRASKA Posts: 8,722	Trigger pulls of less than 2-3 pounds on a gun you may be moving around with over rough terrain, sometimes in a hurry ...... are foolishness. As long as the trigger is crisp and does not require you to pull so hard you disturb your sight picture, then it is good enough. As for cutting springs, grinding on sears and other internal trigger parts..... you are "picking up pfennings on the Autobahn" there....... saving $50 bucks so you can stand a good chance of having a ND (and you modifying the trigger makes it Negligence) and losing everything you have and are ever going to have...... that is just ....... words fail me.

December 22, 2011, 11:09 AM	#22
AllenJ Senior Member Join Date: December 11, 2009 Location: Northern California Posts: 1,766	Thank you dahermit, jimbob86, and peetzalilla, good answers that make sense.

December 22, 2011, 11:15 AM	#23
Elkins45 Senior Member Join Date: February 24, 2010 Posts: 498	Second-hand info here, but I'm under the impression that the Ruger trigger parts are sintered or MIM parts and that they are surfaced hardened only. That means if you stone or file them you are exposing unhardened metal below and your great trigger will turn into an accidental discharge machine in only a few hundred pulls. Again this is second hand, but it does explain why no gunsmith I've ever heard of is willing to stone/polish them and all recommend a replacement instead.

December 22, 2011, 11:29 AM	#25
Brian Pfleuger Moderator Emeritus Join Date: June 25, 2008 Location: Austin, CO Posts: 19,578	Well there you go! I knew there were some metallurgists around here! Why the shallow heat treating? On some parts I can understand but it seems like on a trigger part it would be faster/easier/cheaper to just do the whole thing. __________________ Nobody plans to screw up their lives... ...they just don't plan not to. -Andy Stanley