Polish/improve standard AR trigger?

antsi · January 14, 2009, 12:43 AM

I am in the process of building a second AR-15.

My other AR is a DCM-match style and has a nice 2-stage trigger. I know that the only way to get my new gun that good would be another expensive 2-stage trigger - but funds do not permit this at this time. If it is possible for the "shade tree armorer" to make some improvement to the standard AR trigger I'd like to know how to do that.

I have heard folks speak of the "15 minute AR trigger job" and polishing trigger parts to improve these.

Can anyone link to photos, videos, or other instructions on how to do this?

PS - I am aware of the potential problem of "bubba-ing" off the hardened surface and causing the remaining soft steel parts to fail. Obviously I would like to avoid this outcome

2amencw · January 14, 2009, 10:54 PM

It absolutely works. I can look up the link if you need it. I did it on my precision AR a few years ago and watched my groups shrink and score rocket. Like any mod, go slow and avoid heat. I used very fine files and buffing wheel with both lapping compound and jeweler's rouge. Smooth as glass and still very safe. CW

keys85 · January 15, 2009, 12:16 AM

Another trick which works wonders, and in my opinion makes a WORLD of difference over much anything else, is when fine tuning a stock trigger to bend the hammer spring so much as not get light primer strikes, but enough to take weight off the sear engagement to reduce weight of pull somewhat and get rid of that gritty feel. It definitely smoothens things out as well. Do not clip it as per the 15 minute tirgger job, as I see no reason for this, I haven't tried it and probably would only cause problems. I do not modify the trigger spring.

**Unclenick** · January 15, 2009, 12:51 AM

I don't know whose trigger you bought, but some are quite expensive. Compass Lake's is good, though, and only about $92 last time I looked. A full description and instructions are on their web site.

You can also do the polishing trick. I would mark it with a Sharpie or something and see where the current mating surfaces rub? If you go to the hobby shop, they sell multiple grade Mylar abrasive sheets. Cut these with a knife to fit the sear and trigger engagement. When you pull the strip out it tends to remove metal only at the contact area. Repeating that until the contact is even, then going down through the polishing grades can smooth things up quite a bit.

antsi · January 15, 2009, 09:58 AM

Hmmmm... now I am tempted by the Compass Lake trigger.

Maybe I'll mess around with my stock trigger and ruin it, then buy the Compass Lake

Thanks for the suggestions.

PS - have any of you used the technique of putting lapping compound in the trigger mechanism and cycling it 10 times (rather than stoning or papering or Dremeling?). This seems like the technique that would be easiest to avoid over-doing it.

ccgunworks · January 15, 2009, 12:59 PM

Brownells sells a pre-creep screw that replace the grip screw and pushes the back of the sear down to take out the pre-creep. Used it twice works good. Brings it down to about 3lbs with little to no pre-creep. This was done with Ar-10 and Ar-15 with out any other modifications and the owners were happy. I know the dpms threads per inch are the same 1/4-28 for ar-10 and ar-15. the part number is 072-000-001 for about 34.00

hockeysew · January 16, 2009, 11:39 PM

I cant think of a faster way to ruin a HTS then by putting an abrasive compound onto critical angles/dimensions. Who ever thought this scheme up is probably the same guy who thought up lapping compound on the fire controls of a 1911 and "Shootin her in":barf:
Total bubba trick.
The only CORRECT way is by:
1-Lighter springs-Wolff has them.
2-Knowlegable stone/polishing of engagement surfaces.
3-Pay the price and put in a quality trigger such as a J&P or McCormick. Yes you pay but you get a top quality, SAFE product.

**Unclenick** · January 17, 2009, 12:00 AM

I would include the Compass Lake in the quality circle. The design is simple, which explains the cost, but effective, allowing you to adjust the ratio of the first stage to second stage pull weight. Giving most of the weight to the first stage makes even the 4 1/2 lb service rifle lower limit feel light. Frank White built my 1/2 moa service rifle match AR, which includes his trigger. At trigger weigh-in at one match, the fellow checking triggers snapped mine and declared it way too light; hung the weights and it passed. "Oh," he said, "that must be a Frank White trigger. None of the others fool me like that." Anecdotal, so take it for what it's worth, but that guy must have tried them all at one time or another.

January 14, 2009, 12:43 AM	#1
antsi Member Join Date: April 20, 2002 Posts: 92	Polish/improve standard AR trigger? I am in the process of building a second AR-15. My other AR is a DCM-match style and has a nice 2-stage trigger. I know that the only way to get my new gun that good would be another expensive 2-stage trigger - but funds do not permit this at this time. If it is possible for the "shade tree armorer" to make some improvement to the standard AR trigger I'd like to know how to do that. I have heard folks speak of the "15 minute AR trigger job" and polishing trigger parts to improve these. Can anyone link to photos, videos, or other instructions on how to do this? PS - I am aware of the potential problem of "bubba-ing" off the hardened surface and causing the remaining soft steel parts to fail. Obviously I would like to avoid this outcome

January 14, 2009, 10:54 PM	#2
2amencw Senior Member Join Date: December 3, 2008 Posts: 143	15 min trigger job It absolutely works. I can look up the link if you need it. I did it on my precision AR a few years ago and watched my groups shrink and score rocket. Like any mod, go slow and avoid heat. I used very fine files and buffing wheel with both lapping compound and jeweler's rouge. Smooth as glass and still very safe. CW

January 15, 2009, 12:16 AM	#3
keys85 Junior member Join Date: September 20, 2008 Posts: 199	Another trick which works wonders, and in my opinion makes a WORLD of difference over much anything else, is when fine tuning a stock trigger to bend the hammer spring so much as not get light primer strikes, but enough to take weight off the sear engagement to reduce weight of pull somewhat and get rid of that gritty feel. It definitely smoothens things out as well. Do not clip it as per the 15 minute tirgger job, as I see no reason for this, I haven't tried it and probably would only cause problems. I do not modify the trigger spring. Last edited by keys85; January 15, 2009 at 12:22 AM.

January 15, 2009, 12:51 AM	#4
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	I don't know whose trigger you bought, but some are quite expensive. Compass Lake's is good, though, and only about $92 last time I looked. A full description and instructions are on their web site. You can also do the polishing trick. I would mark it with a Sharpie or something and see where the current mating surfaces rub? If you go to the hobby shop, they sell multiple grade Mylar abrasive sheets. Cut these with a knife to fit the sear and trigger engagement. When you pull the strip out it tends to remove metal only at the contact area. Repeating that until the contact is even, then going down through the polishing grades can smooth things up quite a bit. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle Last edited by Unclenick; January 15, 2009 at 12:58 AM.

January 17, 2009, 12:00 AM	#8
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	I would include the Compass Lake in the quality circle. The design is simple, which explains the cost, but effective, allowing you to adjust the ratio of the first stage to second stage pull weight. Giving most of the weight to the first stage makes even the 4 1/2 lb service rifle lower limit feel light. Frank White built my 1/2 moa service rifle match AR, which includes his trigger. At trigger weigh-in at one match, the fellow checking triggers snapped mine and declared it way too light; hung the weights and it passed. "Oh," he said, "that must be a Frank White trigger. None of the others fool me like that." Anecdotal, so take it for what it's worth, but that guy must have tried them all at one time or another. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

January 15, 2009, 09:58 AM	#5
antsi Member Join Date: April 20, 2002 Posts: 92	Hmmmm... now I am tempted by the Compass Lake trigger. Maybe I'll mess around with my stock trigger and ruin it, then buy the Compass Lake Thanks for the suggestions. PS - have any of you used the technique of putting lapping compound in the trigger mechanism and cycling it 10 times (rather than stoning or papering or Dremeling?). This seems like the technique that would be easiest to avoid over-doing it.

January 15, 2009, 12:59 PM	#6
ccgunworks Junior Member Join Date: January 15, 2009 Location: North Dakota Posts: 8	Brownells sells a pre-creep screw that replace the grip screw and pushes the back of the sear down to take out the pre-creep. Used it twice works good. Brings it down to about 3lbs with little to no pre-creep. This was done with Ar-10 and Ar-15 with out any other modifications and the owners were happy. I know the dpms threads per inch are the same 1/4-28 for ar-10 and ar-15. the part number is 072-000-001 for about 34.00

January 16, 2009, 11:39 PM	#7
hockeysew Member Join Date: August 21, 2008 Posts: 91	I cant think of a faster way to ruin a HTS then by putting an abrasive compound onto critical angles/dimensions. Who ever thought this scheme up is probably the same guy who thought up lapping compound on the fire controls of a 1911 and "Shootin her in":barf: Total bubba trick. The only CORRECT way is by: 1-Lighter springs-Wolff has them. 2-Knowlegable stone/polishing of engagement surfaces. 3-Pay the price and put in a quality trigger such as a J&P or McCormick. Yes you pay but you get a top quality, SAFE product.